Fix OOB write in BuildHuffmanTable.

First, BuildHuffmanTable is called to check if the data is valid.
If it is and the table is not big enough, more memory is allocated.

This will make sure that valid (but unoptimized because of unbalanced
codes) streams are still decodable.

Bug: chromium:1479274
Change-Id: I31c36dbf3aa78d35ecf38706b50464fd3d375741
(cherry picked from commit 902bc91903)
(cherry picked from commit 2af26267cd)

.gitattributes

@@ -1,4 +1,6 @@
 .gitattributes export-ignore
 .gitignore export-ignore
 .mailmap export-ignore
+*.bat text eol=crlf
 *.pdf -text -diff
+*.ppm -text -diff

.gitignore

@@ -1,7 +1,11 @@
 *.l[ao]
 *.[ao]
+*.pc
+.DS_Store
 .deps
+.idea
 .libs
+.vscode
 /aclocal.m4
 /ar-lib
 /autom4te.cache
@@ -14,15 +18,39 @@
 /libtool
 /ltmain.sh
 /missing
+/mkinstalldirs
 /stamp-h1
 Makefile
 Makefile.in
+examples/anim_diff
+examples/anim_dump
 examples/[cdv]webp
 examples/gif2webp
+examples/img2webp
+examples/webpinfo
 examples/webpmux
+src/webp/config.h*
+src/webp/stamp-h1
 /output
 /doc/output
 *.idb
 *.pdb
 /iosbuild
-/WebP.framework
+/xcframeworkbuild
+/WebP*.*framework
+CMakeCache.txt
+CMakeFiles/
+cmake_install.cmake
+.gradle
+/build
+extras/get_disto
+extras/vwebp_sdl
+extras/webp_quality
+tests/fuzzer/advanced_api_fuzzer
+tests/fuzzer/animation_api_fuzzer
+tests/fuzzer/animdecoder_fuzzer
+tests/fuzzer/animencoder_fuzzer
+tests/fuzzer/demux_api_fuzzer
+tests/fuzzer/enc_dec_fuzzer
+tests/fuzzer/mux_demux_api_fuzzer
+tests/fuzzer/simple_api_fuzzer

.mailmap

@@ -1,7 +1,18 @@
-<johann.koenig@duck.com> <johannkoenig@google.com>
+Johann Koenig <johann.koenig@duck.com>
+Johann Koenig <johann.koenig@duck.com> <johannkoenig@google.com>
 Mikołaj Zalewski <mikolajz@google.com>
 Pascal Massimino <pascal.massimino@gmail.com>
-<pascal.massimino@gmail.com> <skal@google.com>
+Pascal Massimino <pascal.massimino@gmail.com> <skal@google.com>
 Vikas Arora <vikasa@google.com>
 <vikasa@google.com> <vikasa@gmail.com>
 <vikasa@google.com> <vikaas.arora@gmail.com>
+<slobodan.prijic@imgtec.com> <Slobodan.Prijic@imgtec.com>
+<vrabaud@google.com> <vincent.rabaud@gmail.com>
+Vincent Rabaud <vrabaud@google.com>
+Tamar Levy <tamar.levy@intel.com>
+<qrczak@google.com> <qrczak>
+Hui Su <huisu@google.com>
+James Zern <jzern@google.com>
+Roberto Alanis <alanisbaez@google.com>
+Brian Ledger <brianpl@google.com>
+Maryla Ustarroz-Calonge <maryla@google.com>

.pylintrc

@@ -0,0 +1,441 @@
+# This Pylint rcfile contains a best-effort configuration to uphold the
+# best-practices and style described in the Google Python style guide:
+#   https://google.github.io/styleguide/pyguide.html
+#
+# Its canonical open-source location is:
+#   https://google.github.io/styleguide/pylintrc
+
+[MASTER]
+
+# Files or directories to be skipped. They should be base names, not paths.
+ignore=third_party
+
+# Files or directories matching the regex patterns are skipped. The regex
+# matches against base names, not paths.
+ignore-patterns=
+
+# Pickle collected data for later comparisons.
+persistent=no
+
+# List of plugins (as comma separated values of python modules names) to load,
+# usually to register additional checkers.
+load-plugins=
+
+# Use multiple processes to speed up Pylint.
+jobs=4
+
+# Allow loading of arbitrary C extensions. Extensions are imported into the
+# active Python interpreter and may run arbitrary code.
+unsafe-load-any-extension=no
+
+
+[MESSAGES CONTROL]
+
+# Only show warnings with the listed confidence levels. Leave empty to show
+# all. Valid levels: HIGH, INFERENCE, INFERENCE_FAILURE, UNDEFINED
+confidence=
+
+# Enable the message, report, category or checker with the given id(s). You can
+# either give multiple identifier separated by comma (,) or put this option
+# multiple time (only on the command line, not in the configuration file where
+# it should appear only once). See also the "--disable" option for examples.
+#enable=
+
+# Disable the message, report, category or checker with the given id(s). You
+# can either give multiple identifiers separated by comma (,) or put this
+# option multiple times (only on the command line, not in the configuration
+# file where it should appear only once).You can also use "--disable=all" to
+# disable everything first and then reenable specific checks. For example, if
+# you want to run only the similarities checker, you can use "--disable=all
+# --enable=similarities". If you want to run only the classes checker, but have
+# no Warning level messages displayed, use"--disable=all --enable=classes
+# --disable=W"
+disable=abstract-method,
+        apply-builtin,
+        arguments-differ,
+        attribute-defined-outside-init,
+        backtick,
+        bad-option-value,
+        basestring-builtin,
+        buffer-builtin,
+        c-extension-no-member,
+        consider-using-enumerate,
+        cmp-builtin,
+        cmp-method,
+        coerce-builtin,
+        coerce-method,
+        delslice-method,
+        div-method,
+        duplicate-code,
+        eq-without-hash,
+        execfile-builtin,
+        file-builtin,
+        filter-builtin-not-iterating,
+        fixme,
+        getslice-method,
+        global-statement,
+        hex-method,
+        idiv-method,
+        implicit-str-concat-in-sequence,
+        import-error,
+        import-self,
+        import-star-module-level,
+        inconsistent-return-statements,
+        input-builtin,
+        intern-builtin,
+        invalid-str-codec,
+        locally-disabled,
+        long-builtin,
+        long-suffix,
+        map-builtin-not-iterating,
+        misplaced-comparison-constant,
+        missing-function-docstring,
+        metaclass-assignment,
+        next-method-called,
+        next-method-defined,
+        no-absolute-import,
+        no-else-break,
+        no-else-continue,
+        no-else-raise,
+        no-else-return,
+        no-init,  # added
+        no-member,
+        no-name-in-module,
+        no-self-use,
+        nonzero-method,
+        oct-method,
+        old-division,
+        old-ne-operator,
+        old-octal-literal,
+        old-raise-syntax,
+        parameter-unpacking,
+        print-statement,
+        raising-string,
+        range-builtin-not-iterating,
+        raw_input-builtin,
+        rdiv-method,
+        reduce-builtin,
+        relative-import,
+        reload-builtin,
+        round-builtin,
+        setslice-method,
+        signature-differs,
+        standarderror-builtin,
+        suppressed-message,
+        sys-max-int,
+        too-few-public-methods,
+        too-many-ancestors,
+        too-many-arguments,
+        too-many-boolean-expressions,
+        too-many-branches,
+        too-many-instance-attributes,
+        too-many-locals,
+        too-many-nested-blocks,
+        too-many-public-methods,
+        too-many-return-statements,
+        too-many-statements,
+        trailing-newlines,
+        unichr-builtin,
+        unicode-builtin,
+        unnecessary-pass,
+        unpacking-in-except,
+        useless-else-on-loop,
+        useless-object-inheritance,
+        useless-suppression,
+        using-cmp-argument,
+        wrong-import-order,
+        xrange-builtin,
+        zip-builtin-not-iterating,
+
+
+[REPORTS]
+
+# Set the output format. Available formats are text, parseable, colorized, msvs
+# (visual studio) and html. You can also give a reporter class, eg
+# mypackage.mymodule.MyReporterClass.
+output-format=text
+
+# Put messages in a separate file for each module / package specified on the
+# command line instead of printing them on stdout. Reports (if any) will be
+# written in a file name "pylint_global.[txt|html]". This option is deprecated
+# and it will be removed in Pylint 2.0.
+files-output=no
+
+# Tells whether to display a full report or only the messages
+reports=no
+
+# Python expression which should return a note less than 10 (10 is the highest
+# note). You have access to the variables errors warning, statement which
+# respectively contain the number of errors / warnings messages and the total
+# number of statements analyzed. This is used by the global evaluation report
+# (RP0004).
+evaluation=10.0 - ((float(5 * error + warning + refactor + convention) / statement) * 10)
+
+# Template used to display messages. This is a python new-style format string
+# used to format the message information. See doc for all details
+#msg-template=
+
+
+[BASIC]
+
+# Good variable names which should always be accepted, separated by a comma
+good-names=main,_,PRESUBMIT
+
+# Bad variable names which should always be refused, separated by a comma
+bad-names=
+
+# Colon-delimited sets of names that determine each other's naming style when
+# the name regexes allow several styles.
+name-group=
+
+# Include a hint for the correct naming format with invalid-name
+include-naming-hint=no
+
+# List of decorators that produce properties, such as abc.abstractproperty. Add
+# to this list to register other decorators that produce valid properties.
+property-classes=abc.abstractproperty,cached_property.cached_property,cached_property.threaded_cached_property,cached_property.cached_property_with_ttl,cached_property.threaded_cached_property_with_ttl
+
+# Regular expression matching correct function names
+function-rgx=^(?:(?P<exempt>setUp|tearDown|setUpModule|tearDownModule)|(?P<camel_case>_?[A-Z][a-zA-Z0-9]*)|(?P<snake_case>_?[a-z][a-z0-9_]*))$
+
+# Regular expression matching correct variable names
+variable-rgx=^[a-z][a-z0-9_]*$
+
+# Regular expression matching correct constant names
+const-rgx=^(_?[A-Z][A-Z0-9_]*|__[a-z0-9_]+__|_?[a-z][a-z0-9_]*)$
+
+# Regular expression matching correct attribute names
+attr-rgx=^_{0,2}[a-z][a-z0-9_]*$
+
+# Regular expression matching correct argument names
+argument-rgx=^[a-z][a-z0-9_]*$
+
+# Regular expression matching correct class attribute names
+class-attribute-rgx=^(_?[A-Z][A-Z0-9_]*|__[a-z0-9_]+__|_?[a-z][a-z0-9_]*)$
+
+# Regular expression matching correct inline iteration names
+inlinevar-rgx=^[a-z][a-z0-9_]*$
+
+# Regular expression matching correct class names
+class-rgx=^_?[A-Z][a-zA-Z0-9]*$
+
+# Regular expression matching correct module names
+module-rgx=^(_?[a-z][a-z0-9_]*|__init__)$
+
+# Regular expression matching correct method names
+method-rgx=(?x)^(?:(?P<exempt>_[a-z0-9_]+__|runTest|setUp|tearDown|setUpTestCase|tearDownTestCase|setupSelf|tearDownClass|setUpClass|(test|assert)_*[A-Z0-9][a-zA-Z0-9_]*|next)|(?P<camel_case>_{0,2}[A-Z][a-zA-Z0-9_]*)|(?P<snake_case>_{0,2}[a-z][a-z0-9_]*))$
+
+# Regular expression which should only match function or class names that do
+# not require a docstring.
+no-docstring-rgx=(__.*__|main|test.*|.*test|.*Test)$
+
+# Minimum line length for functions/classes that require docstrings, shorter
+# ones are exempt.
+docstring-min-length=10
+
+
+[TYPECHECK]
+
+# List of decorators that produce context managers, such as
+# contextlib.contextmanager. Add to this list to register other decorators that
+# produce valid context managers.
+contextmanager-decorators=contextlib.contextmanager,contextlib2.contextmanager
+
+# Tells whether missing members accessed in mixin class should be ignored. A
+# mixin class is detected if its name ends with "mixin" (case insensitive).
+ignore-mixin-members=yes
+
+# List of module names for which member attributes should not be checked
+# (useful for modules/projects where namespaces are manipulated during runtime
+# and thus existing member attributes cannot be deduced by static analysis. It
+# supports qualified module names, as well as Unix pattern matching.
+ignored-modules=
+
+# List of class names for which member attributes should not be checked (useful
+# for classes with dynamically set attributes). This supports the use of
+# qualified names.
+ignored-classes=optparse.Values,thread._local,_thread._local
+
+# List of members which are set dynamically and missed by pylint inference
+# system, and so shouldn't trigger E1101 when accessed. Python regular
+# expressions are accepted.
+generated-members=
+
+
+[FORMAT]
+
+# Maximum number of characters on a single line.
+max-line-length=80
+
+# TODO(https://github.com/PyCQA/pylint/issues/3352): Direct pylint to exempt
+# lines made too long by directives to pytype.
+
+# Regexp for a line that is allowed to be longer than the limit.
+ignore-long-lines=(?x)(
+  ^\s*(\#\ )?<?https?://\S+>?$|
+  ^\s*(from\s+\S+\s+)?import\s+.+$)
+
+# Allow the body of an if to be on the same line as the test if there is no
+# else.
+single-line-if-stmt=yes
+
+# List of optional constructs for which whitespace checking is disabled. `dict-
+# separator` is used to allow tabulation in dicts, etc.: {1  : 1,\n222: 2}.
+# `trailing-comma` allows a space between comma and closing bracket: (a, ).
+# `empty-line` allows space-only lines.
+no-space-check=
+
+# Maximum number of lines in a module
+max-module-lines=99999
+
+# String used as indentation unit.  The internal Google style guide mandates 2
+# spaces.  Google's externaly-published style guide says 4, consistent with
+# PEP 8.  Here, we use 2 spaces, for conformity with many open-sourced Google
+# projects (like TensorFlow).
+indent-string='  '
+
+# Number of spaces of indent required inside a hanging  or continued line.
+indent-after-paren=4
+
+# Expected format of line ending, e.g. empty (any line ending), LF or CRLF.
+expected-line-ending-format=
+
+
+[MISCELLANEOUS]
+
+# List of note tags to take in consideration, separated by a comma.
+notes=TODO
+
+
+[STRING]
+
+# This flag controls whether inconsistent-quotes generates a warning when the
+# character used as a quote delimiter is used inconsistently within a module.
+check-quote-consistency=yes
+
+
+[VARIABLES]
+
+# Tells whether we should check for unused import in __init__ files.
+init-import=no
+
+# A regular expression matching the name of dummy variables (i.e. expectedly
+# not used).
+dummy-variables-rgx=^\*{0,2}(_$|unused_|dummy_)
+
+# List of additional names supposed to be defined in builtins. Remember that
+# you should avoid to define new builtins when possible.
+additional-builtins=
+
+# List of strings which can identify a callback function by name. A callback
+# name must start or end with one of those strings.
+callbacks=cb_,_cb
+
+# List of qualified module names which can have objects that can redefine
+# builtins.
+redefining-builtins-modules=six,six.moves,past.builtins,future.builtins,functools
+
+
+[LOGGING]
+
+# Logging modules to check that the string format arguments are in logging
+# function parameter format
+logging-modules=logging,absl.logging,tensorflow.io.logging
+
+
+[SIMILARITIES]
+
+# Minimum lines number of a similarity.
+min-similarity-lines=4
+
+# Ignore comments when computing similarities.
+ignore-comments=yes
+
+# Ignore docstrings when computing similarities.
+ignore-docstrings=yes
+
+# Ignore imports when computing similarities.
+ignore-imports=no
+
+
+[SPELLING]
+
+# Spelling dictionary name. Available dictionaries: none. To make it working
+# install python-enchant package.
+spelling-dict=
+
+# List of comma separated words that should not be checked.
+spelling-ignore-words=
+
+# A path to a file that contains private dictionary; one word per line.
+spelling-private-dict-file=
+
+# Tells whether to store unknown words to indicated private dictionary in
+# --spelling-private-dict-file option instead of raising a message.
+spelling-store-unknown-words=no
+
+
+[IMPORTS]
+
+# Deprecated modules which should not be used, separated by a comma
+deprecated-modules=regsub,
+                   TERMIOS,
+                   Bastion,
+                   rexec,
+                   sets
+
+# Create a graph of every (i.e. internal and external) dependencies in the
+# given file (report RP0402 must not be disabled)
+import-graph=
+
+# Create a graph of external dependencies in the given file (report RP0402 must
+# not be disabled)
+ext-import-graph=
+
+# Create a graph of internal dependencies in the given file (report RP0402 must
+# not be disabled)
+int-import-graph=
+
+# Force import order to recognize a module as part of the standard
+# compatibility libraries.
+known-standard-library=
+
+# Force import order to recognize a module as part of a third party library.
+known-third-party=enchant, absl
+
+# Analyse import fallback blocks. This can be used to support both Python 2 and
+# 3 compatible code, which means that the block might have code that exists
+# only in one or another interpreter, leading to false positives when analysed.
+analyse-fallback-blocks=no
+
+
+[CLASSES]
+
+# List of method names used to declare (i.e. assign) instance attributes.
+defining-attr-methods=__init__,
+                      __new__,
+                      setUp
+
+# List of member names, which should be excluded from the protected access
+# warning.
+exclude-protected=_asdict,
+                  _fields,
+                  _replace,
+                  _source,
+                  _make
+
+# List of valid names for the first argument in a class method.
+valid-classmethod-first-arg=cls,
+                            class_
+
+# List of valid names for the first argument in a metaclass class method.
+valid-metaclass-classmethod-first-arg=mcs
+
+
+[EXCEPTIONS]
+
+# Exceptions that will emit a warning when being caught. Defaults to
+# "Exception"
+overgeneral-exceptions=StandardError,
+                       Exception,
+                       BaseException

.style.yapf

@@ -0,0 +1,2 @@
+[style]
+based_on_style = chromium

AUTHORS

@@ -1,18 +1,56 @@
 Contributors:
+- Aidan O'Loan (aidanol at gmail dot com)
+- Alan Browning (browning at google dot com)
+- Alexandru Ardelean (ardeleanalex at gmail dot com)
+- Brian Ledger (brianpl at google dot com)
 - Charles Munger (clm at google dot com)
+- Cheng Yi (cyi at google dot com)
 - Christian Duvivier (cduvivier at google dot com)
+- Christopher Degawa (ccom at randomderp dot com)
+- Clement Courbet (courbet at google dot com)
+- Djordje Pesut (djordje dot pesut at imgtec dot com)
+- Frank Barchard (fbarchard at google dot com)
+- Hui Su (huisu at google dot com)
+- Ilya Kurdyukov (jpegqs at gmail dot com)
+- Ingvar Stepanyan (rreverser at google dot com)
 - James Zern (jzern at google dot com)
 - Jan Engelhardt (jengelh at medozas dot de)
-- Johann (johann dot koenig at duck dot com)
+- Jehan (jehan at girinstud dot io)
+- Johann Koenig (johann dot koenig at duck dot com)
+- Jovan Zelincevic (jovan dot zelincevic at imgtec dot com)
 - Jyrki Alakuijala (jyrki at google dot com)
+- Konstantin Ivlev (tomskside at gmail dot com)
+- Lode Vandevenne (lode at google dot com)
 - Lou Quillio (louquillio at google dot com)
 - Mans Rullgard (mans at mansr dot com)
+- Marcin Kowalczyk (qrczak at google dot com)
 - Martin Olsson (mnemo at minimum dot se)
+- Maryla Ustarroz-Calonge (maryla at google dot com)
 - Mikołaj Zalewski (mikolajz at google dot com)
+- Mislav Bradac (mislavm at google dot com)
+- Nico Weber (thakis at chromium dot org)
 - Noel Chromium (noel at chromium dot org)
+- Oliver Wolff (oliver dot wolff at qt dot io)
+- Owen Rodley (orodley at google dot com)
+- Parag Salasakar (img dot mips1 at gmail dot com)
 - Pascal Massimino (pascal dot massimino at gmail dot com)
+- Paweł Hajdan, Jr (phajdan dot jr at chromium dot org)
 - Pierre Joye (pierre dot php at gmail dot com)
+- Roberto Alanis (alanisbaez at google dot com)
+- Sam Clegg (sbc at chromium dot org)
+- Scott Hancher (seh at google dot com)
 - Scott LaVarnway (slavarnway at google dot com)
+- Scott Talbot (s at chikachow dot org)
+- Slobodan Prijic (slobodan dot prijic at imgtec dot com)
 - Somnath Banerjee (somnath dot banerjee at gmail dot com)
+- Sriraman Tallam (tmsriram at google dot com)
+- Tamar Levy (tamar dot levy at intel dot com)
+- Timothy Gu (timothygu99 at gmail dot com)
 - Urvang Joshi (urvang at google dot com)
 - Vikas Arora (vikasa at google dot com)
+- Vincent Rabaud (vrabaud at google dot com)
+- Vlad Tsyrklevich (vtsyrklevich at chromium dot org)
+- Wan-Teh Chang (wtc at google dot com)
+- Yang Zhang (yang dot zhang at arm dot com)
+- Yannis Guyon (yguyon at google dot com)
+- Zhi An Ng (zhin at chromium dot org)

Android.mk

@@ -1,98 +1,290 @@
 LOCAL_PATH := $(call my-dir)
 
 WEBP_CFLAGS := -Wall -DANDROID -DHAVE_MALLOC_H -DHAVE_PTHREAD -DWEBP_USE_THREAD
+WEBP_CFLAGS += -fvisibility=hidden
 
 ifeq ($(APP_OPTIM),release)
-  WEBP_CFLAGS += -finline-functions -frename-registers -ffast-math -s \
+  WEBP_CFLAGS += -finline-functions -ffast-math \
                  -ffunction-sections -fdata-sections
+  ifeq ($(findstring clang,$(NDK_TOOLCHAIN_VERSION)),)
+    WEBP_CFLAGS += -frename-registers -s
+  endif
 endif
 
+# mips32 fails to build with clang from r14b
+# https://bugs.chromium.org/p/webp/issues/detail?id=343
+ifeq ($(findstring clang,$(NDK_TOOLCHAIN_VERSION)),clang)
+  ifeq ($(TARGET_ARCH),mips)
+    clang_version := $(shell $(TARGET_CC) --version)
+    ifneq ($(findstring clang version 3,$(clang_version)),)
+      WEBP_CFLAGS += -no-integrated-as
+    endif
+  endif
+endif
+
+ifneq ($(findstring armeabi-v7a, $(TARGET_ARCH_ABI)),)
+  # Setting LOCAL_ARM_NEON will enable -mfpu=neon which may cause illegal
+  # instructions to be generated for armv7a code. Instead target the neon code
+  # specifically.
+  NEON := c.neon
+  USE_CPUFEATURES := yes
+  WEBP_CFLAGS += -DHAVE_CPU_FEATURES_H
+else
+  NEON := c
+endif
+
+sharpyuv_srcs := \
+    sharpyuv/sharpyuv.c \
+    sharpyuv/sharpyuv_csp.c \
+    sharpyuv/sharpyuv_dsp.c \
+    sharpyuv/sharpyuv_gamma.c \
+    sharpyuv/sharpyuv_neon.$(NEON) \
+    sharpyuv/sharpyuv_sse2.c \
+
+dec_srcs := \
+    src/dec/alpha_dec.c \
+    src/dec/buffer_dec.c \
+    src/dec/frame_dec.c \
+    src/dec/idec_dec.c \
+    src/dec/io_dec.c \
+    src/dec/quant_dec.c \
+    src/dec/tree_dec.c \
+    src/dec/vp8_dec.c \
+    src/dec/vp8l_dec.c \
+    src/dec/webp_dec.c \
+
+demux_srcs := \
+    src/demux/anim_decode.c \
+    src/demux/demux.c \
+
+dsp_dec_srcs := \
+    src/dsp/alpha_processing.c \
+    src/dsp/alpha_processing_mips_dsp_r2.c \
+    src/dsp/alpha_processing_neon.$(NEON) \
+    src/dsp/alpha_processing_sse2.c \
+    src/dsp/alpha_processing_sse41.c \
+    src/dsp/cpu.c \
+    src/dsp/dec.c \
+    src/dsp/dec_clip_tables.c \
+    src/dsp/dec_mips32.c \
+    src/dsp/dec_mips_dsp_r2.c \
+    src/dsp/dec_msa.c \
+    src/dsp/dec_neon.$(NEON) \
+    src/dsp/dec_sse2.c \
+    src/dsp/dec_sse41.c \
+    src/dsp/filters.c \
+    src/dsp/filters_mips_dsp_r2.c \
+    src/dsp/filters_msa.c \
+    src/dsp/filters_neon.$(NEON) \
+    src/dsp/filters_sse2.c \
+    src/dsp/lossless.c \
+    src/dsp/lossless_mips_dsp_r2.c \
+    src/dsp/lossless_msa.c \
+    src/dsp/lossless_neon.$(NEON) \
+    src/dsp/lossless_sse2.c \
+    src/dsp/lossless_sse41.c \
+    src/dsp/rescaler.c \
+    src/dsp/rescaler_mips32.c \
+    src/dsp/rescaler_mips_dsp_r2.c \
+    src/dsp/rescaler_msa.c \
+    src/dsp/rescaler_neon.$(NEON) \
+    src/dsp/rescaler_sse2.c \
+    src/dsp/upsampling.c \
+    src/dsp/upsampling_mips_dsp_r2.c \
+    src/dsp/upsampling_msa.c \
+    src/dsp/upsampling_neon.$(NEON) \
+    src/dsp/upsampling_sse2.c \
+    src/dsp/upsampling_sse41.c \
+    src/dsp/yuv.c \
+    src/dsp/yuv_mips32.c \
+    src/dsp/yuv_mips_dsp_r2.c \
+    src/dsp/yuv_neon.$(NEON) \
+    src/dsp/yuv_sse2.c \
+    src/dsp/yuv_sse41.c \
+
+dsp_enc_srcs := \
+    src/dsp/cost.c \
+    src/dsp/cost_mips32.c \
+    src/dsp/cost_mips_dsp_r2.c \
+    src/dsp/cost_neon.$(NEON) \
+    src/dsp/cost_sse2.c \
+    src/dsp/enc.c \
+    src/dsp/enc_mips32.c \
+    src/dsp/enc_mips_dsp_r2.c \
+    src/dsp/enc_msa.c \
+    src/dsp/enc_neon.$(NEON) \
+    src/dsp/enc_sse2.c \
+    src/dsp/enc_sse41.c \
+    src/dsp/lossless_enc.c \
+    src/dsp/lossless_enc_mips32.c \
+    src/dsp/lossless_enc_mips_dsp_r2.c \
+    src/dsp/lossless_enc_msa.c \
+    src/dsp/lossless_enc_neon.$(NEON) \
+    src/dsp/lossless_enc_sse2.c \
+    src/dsp/lossless_enc_sse41.c \
+    src/dsp/ssim.c \
+    src/dsp/ssim_sse2.c \
+
+enc_srcs := \
+    src/enc/alpha_enc.c \
+    src/enc/analysis_enc.c \
+    src/enc/backward_references_cost_enc.c \
+    src/enc/backward_references_enc.c \
+    src/enc/config_enc.c \
+    src/enc/cost_enc.c \
+    src/enc/filter_enc.c \
+    src/enc/frame_enc.c \
+    src/enc/histogram_enc.c \
+    src/enc/iterator_enc.c \
+    src/enc/near_lossless_enc.c \
+    src/enc/picture_enc.c \
+    src/enc/picture_csp_enc.c \
+    src/enc/picture_psnr_enc.c \
+    src/enc/picture_rescale_enc.c \
+    src/enc/picture_tools_enc.c \
+    src/enc/predictor_enc.c \
+    src/enc/quant_enc.c \
+    src/enc/syntax_enc.c \
+    src/enc/token_enc.c \
+    src/enc/tree_enc.c \
+    src/enc/vp8l_enc.c \
+    src/enc/webp_enc.c \
+
+mux_srcs := \
+    src/mux/anim_encode.c \
+    src/mux/muxedit.c \
+    src/mux/muxinternal.c \
+    src/mux/muxread.c \
+
+utils_dec_srcs := \
+    src/utils/bit_reader_utils.c \
+    src/utils/color_cache_utils.c \
+    src/utils/filters_utils.c \
+    src/utils/huffman_utils.c \
+    src/utils/quant_levels_dec_utils.c \
+    src/utils/random_utils.c \
+    src/utils/rescaler_utils.c \
+    src/utils/thread_utils.c \
+    src/utils/utils.c \
+
+utils_enc_srcs := \
+    src/utils/bit_writer_utils.c \
+    src/utils/huffman_encode_utils.c \
+    src/utils/quant_levels_utils.c \
+
+################################################################################
+# libwebpdecoder
+
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES := \
-    src/dec/alpha.c \
-    src/dec/buffer.c \
-    src/dec/frame.c \
-    src/dec/idec.c \
-    src/dec/io.c \
-    src/dec/layer.c \
-    src/dec/quant.c \
-    src/dec/tree.c \
-    src/dec/vp8.c \
-    src/dec/vp8l.c \
-    src/dec/webp.c \
-    src/dsp/cpu.c \
-    src/dsp/dec.c \
-    src/dsp/dec_sse2.c \
-    src/dsp/enc.c \
-    src/dsp/enc_sse2.c \
-    src/dsp/lossless.c \
-    src/dsp/upsampling.c \
-    src/dsp/upsampling_sse2.c \
-    src/dsp/yuv.c \
-    src/enc/alpha.c \
-    src/enc/analysis.c \
-    src/enc/backward_references.c \
-    src/enc/config.c \
-    src/enc/cost.c \
-    src/enc/filter.c \
-    src/enc/frame.c \
-    src/enc/histogram.c \
-    src/enc/iterator.c \
-    src/enc/layer.c \
-    src/enc/picture.c \
-    src/enc/quant.c \
-    src/enc/syntax.c \
-    src/enc/token.c \
-    src/enc/tree.c \
-    src/enc/vp8l.c \
-    src/enc/webpenc.c \
-    src/utils/alpha_processing.c \
-    src/utils/bit_reader.c \
-    src/utils/bit_writer.c \
-    src/utils/color_cache.c \
-    src/utils/filters.c \
-    src/utils/huffman.c \
-    src/utils/huffman_encode.c \
-    src/utils/quant_levels.c \
-    src/utils/quant_levels_dec.c \
-    src/utils/random.c \
-    src/utils/rescaler.c \
-    src/utils/thread.c \
-    src/utils/utils.c \
+    $(dec_srcs) \
+    $(dsp_dec_srcs) \
+    $(utils_dec_srcs) \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES += $(LOCAL_PATH)/src
+LOCAL_EXPORT_C_INCLUDES += $(LOCAL_PATH)/src
 
 # prefer arm over thumb mode for performance gains
 LOCAL_ARM_MODE := arm
 
-ifeq ($(TARGET_ARCH_ABI),armeabi-v7a)
-  # Setting LOCAL_ARM_NEON will enable -mfpu=neon which may cause illegal
-  # instructions to be generated for armv7a code. Instead target the neon code
-  # specifically.
-  LOCAL_SRC_FILES += src/dsp/dec_neon.c.neon
-  LOCAL_SRC_FILES += src/dsp/upsampling_neon.c.neon
-  LOCAL_SRC_FILES += src/dsp/enc_neon.c.neon
+ifeq ($(USE_CPUFEATURES),yes)
+  LOCAL_STATIC_LIBRARIES := cpufeatures
 endif
-LOCAL_STATIC_LIBRARIES := cpufeatures
 
-LOCAL_MODULE := webp
+LOCAL_MODULE := webpdecoder_static
 
 include $(BUILD_STATIC_LIBRARY)
 
+ifeq ($(ENABLE_SHARED),1)
+include $(CLEAR_VARS)
+
+LOCAL_WHOLE_STATIC_LIBRARIES := webpdecoder_static
+
+LOCAL_MODULE := webpdecoder
+
+include $(BUILD_SHARED_LIBRARY)
+endif  # ENABLE_SHARED=1
+
+################################################################################
+# libwebp
+
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES := \
-    examples/dwebp.c \
-    examples/example_util.c \
+    $(sharpyuv_srcs) \
+    $(dsp_enc_srcs) \
+    $(enc_srcs) \
+    $(utils_enc_srcs) \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES := $(LOCAL_PATH)/src
-LOCAL_STATIC_LIBRARIES := webp
+LOCAL_EXPORT_C_INCLUDES += $(LOCAL_PATH)/src
 
-LOCAL_MODULE := dwebp
+# prefer arm over thumb mode for performance gains
+LOCAL_ARM_MODE := arm
 
-include $(BUILD_EXECUTABLE)
+LOCAL_WHOLE_STATIC_LIBRARIES := webpdecoder_static
 
-$(call import-module,android/cpufeatures)
+LOCAL_MODULE := webp
+
+ifeq ($(ENABLE_SHARED),1)
+  include $(BUILD_SHARED_LIBRARY)
+else
+  include $(BUILD_STATIC_LIBRARY)
+endif
+
+################################################################################
+# libwebpdemux
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := $(demux_srcs)
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_EXPORT_C_INCLUDES += $(LOCAL_PATH)/src
+
+# prefer arm over thumb mode for performance gains
+LOCAL_ARM_MODE := arm
+
+LOCAL_MODULE := webpdemux
+
+ifeq ($(ENABLE_SHARED),1)
+  LOCAL_SHARED_LIBRARIES := webp
+  include $(BUILD_SHARED_LIBRARY)
+else
+  LOCAL_STATIC_LIBRARIES := webp
+  include $(BUILD_STATIC_LIBRARY)
+endif
+
+################################################################################
+# libwebpmux
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := $(mux_srcs)
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_EXPORT_C_INCLUDES += $(LOCAL_PATH)/src
+
+# prefer arm over thumb mode for performance gains
+LOCAL_ARM_MODE := arm
+
+LOCAL_MODULE := webpmux
+
+ifeq ($(ENABLE_SHARED),1)
+  LOCAL_SHARED_LIBRARIES := webp
+  include $(BUILD_SHARED_LIBRARY)
+else
+  LOCAL_STATIC_LIBRARIES := webp
+  include $(BUILD_STATIC_LIBRARY)
+endif
+
+################################################################################
+
+WEBP_SRC_PATH := $(LOCAL_PATH)
+include $(WEBP_SRC_PATH)/imageio/Android.mk
+include $(WEBP_SRC_PATH)/examples/Android.mk
+
+ifeq ($(USE_CPUFEATURES),yes)
+  $(call import-module,android/cpufeatures)
+endif

CMakeLists.txt

@@ -0,0 +1,780 @@
+#  Copyright (c) 2020 Google LLC.
+#
+#  Use of this source code is governed by a BSD-style license
+#  that can be found in the LICENSE file in the root of the source
+#  tree. An additional intellectual property rights grant can be found
+#  in the file PATENTS.  All contributing project authors may
+#  be found in the AUTHORS file in the root of the source tree.
+
+cmake_minimum_required(VERSION 3.7)
+
+if(POLICY CMP0072)
+  cmake_policy(SET CMP0072 NEW)
+endif()
+
+project(WebP C)
+
+# Options for coder / decoder executables.
+if(BUILD_SHARED_LIBS)
+  set(WEBP_LINK_STATIC_DEFAULT OFF)
+else()
+  set(WEBP_LINK_STATIC_DEFAULT ON)
+endif()
+option(WEBP_LINK_STATIC
+       "Link using static libraries. If OFF, use dynamic libraries."
+       ${WEBP_LINK_STATIC_DEFAULT})
+if(NOT EMSCRIPTEN)
+  # Disable SIMD on Emscripten by default, as it's a new unstable Wasm feature.
+  # Users can still explicitly opt-in to make a SIMD-enabled build.
+  set(WEBP_ENABLE_SIMD_DEFAULT ON)
+endif()
+option(WEBP_ENABLE_SIMD "Enable any SIMD optimization."
+       ${WEBP_ENABLE_SIMD_DEFAULT})
+option(WEBP_BUILD_ANIM_UTILS "Build animation utilities." ON)
+option(WEBP_BUILD_CWEBP "Build the cwebp command line tool." ON)
+option(WEBP_BUILD_DWEBP "Build the dwebp command line tool." ON)
+option(WEBP_BUILD_GIF2WEBP "Build the gif2webp conversion tool." ON)
+option(WEBP_BUILD_IMG2WEBP "Build the img2webp animation tool." ON)
+option(WEBP_BUILD_VWEBP "Build the vwebp viewer tool." ON)
+option(WEBP_BUILD_WEBPINFO "Build the webpinfo command line tool." ON)
+option(WEBP_BUILD_LIBWEBPMUX "Build the libwebpmux library." ON)
+option(WEBP_BUILD_WEBPMUX "Build the webpmux command line tool." ON)
+option(WEBP_BUILD_EXTRAS "Build extras." ON)
+option(WEBP_BUILD_WEBP_JS "Emscripten build of webp.js." OFF)
+option(WEBP_USE_THREAD "Enable threading support" ON)
+option(WEBP_NEAR_LOSSLESS "Enable near-lossless encoding" ON)
+option(WEBP_ENABLE_SWAP_16BIT_CSP "Enable byte swap for 16 bit colorspaces."
+       OFF)
+set(WEBP_BITTRACE "0" CACHE STRING "Bit trace mode (0=none, 1=bit, 2=bytes)")
+set_property(CACHE WEBP_BITTRACE PROPERTY STRINGS 0 1 2)
+
+if(WEBP_LINK_STATIC)
+  if(WIN32)
+    SET(CMAKE_FIND_LIBRARY_SUFFIXES .lib .a ${CMAKE_FIND_LIBRARY_SUFFIXES})
+  else()
+    SET(CMAKE_FIND_LIBRARY_SUFFIXES .a ${CMAKE_FIND_LIBRARY_SUFFIXES})
+  endif()
+  set(CMAKE_POSITION_INDEPENDENT_CODE ON)
+  # vwebp does not compile on Ubuntu with static libraries so disabling it for
+  # now.
+  set(WEBP_BUILD_VWEBP OFF)
+endif()
+
+# Option needed for handling Unicode file names on Windows.
+if(WIN32)
+  option(WEBP_UNICODE "Build Unicode executables." ON)
+endif()
+
+if(WEBP_BUILD_WEBP_JS)
+  set(WEBP_BUILD_ANIM_UTILS OFF)
+  set(WEBP_BUILD_CWEBP OFF)
+  set(WEBP_BUILD_DWEBP OFF)
+  set(WEBP_BUILD_GIF2WEBP OFF)
+  set(WEBP_BUILD_IMG2WEBP OFF)
+  set(WEBP_BUILD_VWEBP OFF)
+  set(WEBP_BUILD_WEBPINFO OFF)
+  set(WEBP_BUILD_WEBPMUX OFF)
+  set(WEBP_BUILD_EXTRAS OFF)
+  set(WEBP_USE_THREAD OFF)
+
+  if(WEBP_ENABLE_SIMD)
+    message("wasm2js does not support SIMD, disabling webp.js generation.")
+  endif()
+endif()
+
+set(WEBP_DEP_LIBRARIES)
+set(WEBP_DEP_INCLUDE_DIRS)
+
+if(NOT CMAKE_BUILD_TYPE)
+  set(CMAKE_BUILD_TYPE "Release"
+      CACHE STRING "Build type: Release, Debug, MinSizeRel or RelWithDebInfo"
+      FORCE)
+endif()
+
+# Include dependencies.
+include(cmake/deps.cmake)
+include(GNUInstallDirs)
+
+# ##############################################################################
+# Options.
+if(WEBP_ENABLE_SWAP_16BIT_CSP)
+  add_definitions(-DWEBP_SWAP_16BIT_CSP=1)
+endif()
+
+if(NOT WEBP_BITTRACE STREQUAL "0")
+  add_definitions(-DBITTRACE=${WEBP_BITTRACE})
+endif()
+
+if(WEBP_UNICODE)
+  # Windows recommends setting both UNICODE and _UNICODE.
+  add_definitions(-DUNICODE -D_UNICODE)
+endif()
+
+set(prefix ${CMAKE_INSTALL_PREFIX})
+set(exec_prefix "\$\{prefix\}")
+set(libdir "\$\{prefix\}/lib")
+set(includedir "\$\{prefix\}/include")
+set(PTHREAD_LIBS ${CMAKE_THREAD_LIBS_INIT})
+set(INSTALLED_LIBRARIES)
+
+set(CMAKE_C_VISIBILITY_PRESET hidden)
+
+# ##############################################################################
+# Android only.
+if(ANDROID)
+  include_directories(${ANDROID_NDK}/sources/android/cpufeatures)
+  add_library(cpufeatures STATIC
+              ${ANDROID_NDK}/sources/android/cpufeatures/cpu-features.c)
+  list(APPEND INSTALLED_LIBRARIES cpufeatures)
+  target_link_libraries(cpufeatures dl)
+  set(WEBP_DEP_LIBRARIES ${WEBP_DEP_LIBRARIES} cpufeatures)
+  set(WEBP_DEP_INCLUDE_DIRS ${WEBP_DEP_INCLUDE_DIRS}
+      ${ANDROID_NDK}/sources/android/cpufeatures)
+  add_definitions(-DHAVE_CPU_FEATURES_H=1)
+  set(HAVE_CPU_FEATURES_H 1)
+else()
+  set(HAVE_CPU_FEATURES_H 0)
+endif()
+
+function(configure_pkg_config FILE)
+  configure_file("${CMAKE_CURRENT_SOURCE_DIR}/${FILE}.in"
+                 "${CMAKE_CURRENT_BINARY_DIR}/${FILE}")
+
+  if(HAVE_MATH_LIBRARY)
+    # MSVC doesn't have libm
+    file(READ ${CMAKE_CURRENT_BINARY_DIR}/${FILE} data)
+    string(REPLACE "-lm" "" data ${data})
+    file(WRITE ${CMAKE_CURRENT_BINARY_DIR}/${FILE} ${data})
+  endif()
+
+  install(
+    FILES "${CMAKE_CURRENT_BINARY_DIR}/${FILE}"
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/pkgconfig
+  )
+endfunction()
+
+# ##############################################################################
+# WebP source files. Read the Makefile.am to get the source files.
+
+# We expect the Makefiles to define the sources as defined in the first regex.
+# E.g.: libimagedec_la_SOURCES  = image_dec.c image_dec.h
+function(parse_Makefile_am FOLDER VAR SRC_REGEX)
+  file(READ ${FOLDER}/Makefile.am MAKEFILE_AM)
+  string(REGEX MATCHALL
+               "${SRC_REGEX}_SOURCES[ ]*\\+?=[ ]+[0-9a-z\\._ ]*"
+               FILES_PER_LINE
+               ${MAKEFILE_AM})
+  set(SRCS ${${VAR}})
+  foreach(FILES ${FILES_PER_LINE})
+    string(FIND ${FILES} "=" OFFSET)
+    math(EXPR OFFSET "${OFFSET} + 2")
+    string(SUBSTRING ${FILES}
+                     ${OFFSET}
+                     -1
+                     FILES)
+    if(FILES)
+      string(REGEX MATCHALL
+                   "[0-9a-z\\._]+"
+                   FILES
+                   ${FILES})
+      foreach(FILE ${FILES})
+        list(APPEND SRCS ${FOLDER}/${FILE})
+      endforeach()
+    endif()
+  endforeach()
+  set(${VAR} ${SRCS} PARENT_SCOPE)
+endfunction()
+
+set(WEBP_SRC_DIR ${CMAKE_CURRENT_SOURCE_DIR}/src)
+parse_makefile_am(${WEBP_SRC_DIR}/dec "WEBP_DEC_SRCS" "")
+parse_makefile_am(${WEBP_SRC_DIR}/demux "WEBP_DEMUX_SRCS" "")
+parse_makefile_am(${WEBP_SRC_DIR}/dsp "WEBP_DSP_COMMON_SRCS" "COMMON")
+parse_makefile_am(${WEBP_SRC_DIR}/dsp "WEBP_DSP_ENC_SRCS" "ENC")
+parse_makefile_am(${WEBP_SRC_DIR}/dsp "WEBP_DSP_ENC_SRCS" "dsp_[^ ]*")
+parse_makefile_am(${WEBP_SRC_DIR}/dsp "WEBP_DSP_DEC_SRCS" "decode_[^ ]*")
+parse_makefile_am(${WEBP_SRC_DIR}/enc "WEBP_ENC_SRCS" "")
+parse_makefile_am(${WEBP_SRC_DIR}/utils "WEBP_UTILS_COMMON_SRCS" "COMMON")
+parse_makefile_am(${WEBP_SRC_DIR}/utils "WEBP_UTILS_ENC_SRCS" "ENC")
+parse_makefile_am(${WEBP_SRC_DIR}/utils "WEBP_UTILS_DEC_SRCS" "decode_[^ ]*")
+
+# Remove the files specific to SIMD we don't use.
+foreach(FILE ${WEBP_SIMD_FILES_NOT_TO_INCLUDE})
+  list(REMOVE_ITEM WEBP_DSP_ENC_SRCS ${FILE})
+  list(REMOVE_ITEM WEBP_DSP_DEC_SRCS ${FILE})
+endforeach()
+
+# Generate the config.h file.
+configure_file(${CMAKE_CURRENT_LIST_DIR}/cmake/config.h.in
+               ${CMAKE_CURRENT_BINARY_DIR}/src/webp/config.h)
+add_definitions(-DHAVE_CONFIG_H)
+
+# ##############################################################################
+# Build the webpdecoder library.
+
+# Creates a source file with an unused stub function in $CMAKE_BINARY_DIR and
+# adds it to the specified target. Currently used only with Xcode.
+#
+# See also:
+# https://cmake.org/cmake/help/v3.18/command/add_library.html#object-libraries
+# "Some native build systems (such as Xcode) may not like targets that have
+# only object files, so consider adding at least one real source file to any
+# target that references $<TARGET_OBJECTS:objlib>."
+function(libwebp_add_stub_file TARGET)
+  set(stub_source_dir "${CMAKE_BINARY_DIR}")
+  set(stub_source_file
+      "${stub_source_dir}/libwebp_${TARGET}_stub.c")
+  set(stub_source_code
+      "// Generated file. DO NOT EDIT!\n"
+      "// C source file created for target ${TARGET}.\n"
+      "void libwebp_${TARGET}_stub_function(void)\;\n"
+      "void libwebp_${TARGET}_stub_function(void) {}\n")
+  file(WRITE "${stub_source_file}" ${stub_source_code})
+
+  target_sources(${TARGET} PRIVATE ${stub_source_file})
+endfunction()
+
+parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/sharpyuv "WEBP_SHARPYUV_SRCS"
+                  "")
+add_library(sharpyuv OBJECT ${WEBP_SHARPYUV_SRCS})
+target_include_directories(sharpyuv
+                            PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                            ${CMAKE_CURRENT_SOURCE_DIR})
+set_target_properties(
+  sharpyuv
+  PROPERTIES PUBLIC_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/sharpyuv/sharpyuv.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/sharpyuv/sharpyuv_csp.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/types.h")
+
+if(MSVC)
+  # avoid security warnings for e.g., fopen() used in the examples.
+  add_definitions(-D_CRT_SECURE_NO_WARNINGS)
+else()
+  add_definitions(-Wall)
+endif()
+include_directories(${WEBP_DEP_INCLUDE_DIRS})
+add_library(webpdecode OBJECT ${WEBP_DEC_SRCS})
+target_include_directories(webpdecode
+                           PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                                   ${CMAKE_CURRENT_SOURCE_DIR})
+add_library(webpdspdecode OBJECT ${WEBP_DSP_COMMON_SRCS} ${WEBP_DSP_DEC_SRCS})
+target_include_directories(webpdspdecode
+                           PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                                   ${CMAKE_CURRENT_SOURCE_DIR})
+add_library(webputilsdecode
+            OBJECT
+            ${WEBP_UTILS_COMMON_SRCS}
+            ${WEBP_UTILS_DEC_SRCS})
+target_include_directories(webputilsdecode
+                           PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                                   ${CMAKE_CURRENT_SOURCE_DIR})
+add_library(webpdecoder
+            $<TARGET_OBJECTS:webpdecode>
+            $<TARGET_OBJECTS:webpdspdecode>
+            $<TARGET_OBJECTS:webputilsdecode>)
+if(XCODE)
+  libwebp_add_stub_file(webpdecoder)
+endif()
+target_link_libraries(webpdecoder ${WEBP_DEP_LIBRARIES})
+target_include_directories(
+  webpdecoder
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}
+  INTERFACE $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
+            $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>)
+set_target_properties(
+  webpdecoder
+  PROPERTIES PUBLIC_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/src/webp/decode.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/types.h")
+
+configure_pkg_config("src/libwebpdecoder.pc")
+
+# Build the webp library.
+add_library(webpencode OBJECT ${WEBP_ENC_SRCS})
+target_include_directories(webpencode
+                           PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                                   ${CMAKE_CURRENT_SOURCE_DIR})
+add_library(webpdsp
+            OBJECT
+            ${WEBP_DSP_COMMON_SRCS}
+            ${WEBP_DSP_DEC_SRCS}
+            ${WEBP_DSP_ENC_SRCS})
+target_include_directories(webpdsp
+                           PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                                   ${CMAKE_CURRENT_SOURCE_DIR})
+add_library(webputils
+            OBJECT
+            ${WEBP_UTILS_COMMON_SRCS}
+            ${WEBP_UTILS_DEC_SRCS}
+            ${WEBP_UTILS_ENC_SRCS})
+target_include_directories(webputils
+                           PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                                   ${CMAKE_CURRENT_SOURCE_DIR})
+add_library(webp
+            $<TARGET_OBJECTS:sharpyuv>
+            $<TARGET_OBJECTS:webpdecode>
+            $<TARGET_OBJECTS:webpdsp>
+            $<TARGET_OBJECTS:webpencode>
+            $<TARGET_OBJECTS:webputils>)
+if(XCODE)
+  libwebp_add_stub_file(webp)
+endif()
+target_link_libraries(webp ${WEBP_DEP_LIBRARIES})
+target_include_directories(
+  webp
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+          ${CMAKE_CURRENT_BINARY_DIR}
+  PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>
+         $<INSTALL_INTERFACE:include>)
+set_target_properties(
+  webp
+  PROPERTIES PUBLIC_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/src/webp/decode.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/encode.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/types.h")
+
+# Make sure the OBJECT libraries are built with position independent code (it is
+# not ON by default).
+set_target_properties(sharpyuv
+                      webpdecode
+                      webpdspdecode
+                      webputilsdecode
+                      webpencode
+                      webpdsp
+                      webputils
+                      PROPERTIES POSITION_INDEPENDENT_CODE ON)
+configure_pkg_config("src/libwebp.pc")
+
+# Build the webp demux library.
+add_library(webpdemux ${WEBP_DEMUX_SRCS})
+target_link_libraries(webpdemux webp)
+target_include_directories(webpdemux
+                           PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+                                   ${CMAKE_CURRENT_BINARY_DIR}
+                           PUBLIC $<INSTALL_INTERFACE:include>)
+set_target_properties(
+  webpdemux
+  PROPERTIES PUBLIC_HEADER "${CMAKE_CURRENT_SOURCE_DIR}/src/webp/decode.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/demux.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/mux_types.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/types.h")
+
+configure_pkg_config("src/demux/libwebpdemux.pc")
+
+# Set the version numbers.
+macro(set_version FILE TARGET_NAME NAME_IN_MAKEFILE)
+  file(READ ${CMAKE_CURRENT_SOURCE_DIR}/src/${FILE} SOURCE_FILE)
+  string(REGEX MATCH
+               "${NAME_IN_MAKEFILE}_la_LDFLAGS[^\n]* -version-info [0-9:]+"
+               TMP
+               ${SOURCE_FILE})
+  string(REGEX MATCH
+               "[0-9:]+"
+               TMP
+               ${TMP})
+  string(REGEX
+         REPLACE ":"
+                 " "
+                 LT_VERSION
+                 ${TMP})
+
+  # See the libtool docs for more information:
+  # https://www.gnu.org/software/libtool/manual/libtool.html#Updating-version-info
+  #
+  # c=<current>, a=<age>, r=<revision>
+  #
+  # libtool generates a .so file as .so.[c-a].a.r, while -version-info c:r:a is
+  # passed to libtool.
+  #
+  # We set FULL = [c-a].a.r and MAJOR = [c-a].
+  separate_arguments(LT_VERSION)
+  list(GET LT_VERSION 0 LT_CURRENT)
+  list(GET LT_VERSION 1 LT_REVISION)
+  list(GET LT_VERSION 2 LT_AGE)
+  math(EXPR LT_CURRENT_MINUS_AGE "${LT_CURRENT} - ${LT_AGE}")
+
+  set_target_properties(
+    ${TARGET_NAME}
+    PROPERTIES VERSION
+               ${LT_CURRENT_MINUS_AGE}.${LT_AGE}.${LT_REVISION}
+               SOVERSION
+               ${LT_CURRENT_MINUS_AGE})
+endmacro()
+set_version(Makefile.am webp webp)
+set_version(Makefile.am webpdecoder webpdecoder)
+set_version(demux/Makefile.am webpdemux webpdemux)
+file(READ ${CMAKE_CURRENT_SOURCE_DIR}/configure.ac CONFIGURE_FILE)
+string(REGEX MATCH
+             "AC_INIT\\([^\n]*\\[[0-9\\.]+\\]"
+             TMP
+             ${CONFIGURE_FILE})
+string(REGEX MATCH
+             "[0-9\\.]+"
+             PROJECT_VERSION
+             ${TMP})
+
+# Define the libraries to install.
+list(APPEND INSTALLED_LIBRARIES webpdecoder webp webpdemux)
+
+# Deal with SIMD. Change the compile flags for SIMD files we use.
+list(LENGTH WEBP_SIMD_FILES_TO_INCLUDE WEBP_SIMD_FILES_TO_INCLUDE_LENGTH)
+math(EXPR WEBP_SIMD_FILES_TO_INCLUDE_RANGE
+     "${WEBP_SIMD_FILES_TO_INCLUDE_LENGTH}-1")
+
+foreach(I_FILE RANGE ${WEBP_SIMD_FILES_TO_INCLUDE_RANGE})
+  list(GET WEBP_SIMD_FILES_TO_INCLUDE ${I_FILE} FILE)
+  list(GET WEBP_SIMD_FLAGS_TO_INCLUDE ${I_FILE} SIMD_COMPILE_FLAG)
+  set_source_files_properties(${FILE}
+                              PROPERTIES
+                              COMPILE_FLAGS
+                              ${SIMD_COMPILE_FLAG})
+endforeach()
+
+if(NOT WEBP_BUILD_LIBWEBPMUX)
+  set(WEBP_BUILD_GIF2WEBP OFF)
+  set(WEBP_BUILD_IMG2WEBP OFF)
+  set(WEBP_BUILD_WEBPMUX OFF)
+endif()
+
+if(WEBP_BUILD_GIF2WEBP AND NOT GIF_FOUND)
+  set(WEBP_BUILD_GIF2WEBP OFF)
+endif()
+
+if(WEBP_BUILD_ANIM_UTILS AND NOT GIF_FOUND)
+  set(WEBP_BUILD_ANIM_UTILS OFF)
+endif()
+
+# Build the executables if asked for.
+if(WEBP_BUILD_ANIM_UTILS
+   OR WEBP_BUILD_CWEBP
+   OR WEBP_BUILD_DWEBP
+   OR WEBP_BUILD_GIF2WEBP
+   OR WEBP_BUILD_IMG2WEBP
+   OR WEBP_BUILD_VWEBP
+   OR WEBP_BUILD_WEBPMUX
+   OR WEBP_BUILD_WEBPINFO)
+  # Example utility library.
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "EXAMPLEUTIL_SRCS"
+                    "example_util_[^ ]*")
+  list(APPEND EXAMPLEUTIL_SRCS ${CMAKE_CURRENT_SOURCE_DIR}/examples/stopwatch.h)
+  add_library(exampleutil STATIC ${EXAMPLEUTIL_SRCS})
+  target_include_directories(
+    exampleutil
+    PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/src>)
+
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/imageio "IMAGEIOUTILS_SRCS"
+                    "imageio_util_[^ ]*")
+  add_library(imageioutil STATIC ${IMAGEIOUTILS_SRCS})
+  target_link_libraries(imageioutil webp)
+  target_link_libraries(exampleutil imageioutil)
+
+  # Image-decoding utility library.
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/imageio "IMAGEDEC_SRCS"
+                    "imagedec_[^ ]*")
+  add_library(imagedec STATIC ${IMAGEDEC_SRCS})
+  target_link_libraries(imagedec
+                        imageioutil
+                        webpdemux
+                        webp
+                        ${WEBP_DEP_IMG_LIBRARIES})
+
+  # Image-encoding utility library.
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/imageio "IMAGEENC_SRCS"
+                    "imageenc_[^ ]*")
+  add_library(imageenc STATIC ${IMAGEENC_SRCS})
+  target_link_libraries(imageenc imageioutil webp)
+
+  set_property(TARGET exampleutil
+                      imageioutil
+                      imagedec
+                      imageenc
+               PROPERTY INCLUDE_DIRECTORIES ${CMAKE_CURRENT_SOURCE_DIR}/src
+                        ${CMAKE_CURRENT_BINARY_DIR}/src)
+endif()
+
+if(WEBP_BUILD_DWEBP)
+  # dwebp
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "DWEBP_SRCS" "dwebp")
+  add_executable(dwebp ${DWEBP_SRCS})
+  target_link_libraries(dwebp exampleutil imagedec imageenc)
+  target_include_directories(dwebp PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+  install(TARGETS dwebp RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+endif()
+
+if(WEBP_BUILD_CWEBP)
+  # cwebp
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "CWEBP_SRCS" "cwebp")
+  add_executable(cwebp ${CWEBP_SRCS})
+  target_link_libraries(cwebp exampleutil imagedec webp)
+  target_include_directories(cwebp PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+  install(TARGETS cwebp RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+endif()
+
+if(WEBP_BUILD_LIBWEBPMUX)
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/src/mux "WEBP_MUX_SRCS" "")
+  add_library(webpmux ${WEBP_MUX_SRCS})
+  target_link_libraries(webpmux webp)
+  target_include_directories(webpmux
+                             PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                                     ${CMAKE_CURRENT_SOURCE_DIR})
+  set_version(mux/Makefile.am webpmux webpmux)
+  set_target_properties(webpmux
+                        PROPERTIES PUBLIC_HEADER
+                                   "${CMAKE_CURRENT_SOURCE_DIR}/src/webp/mux.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/mux_types.h;\
+${CMAKE_CURRENT_SOURCE_DIR}/src/webp/types.h;")
+  list(APPEND INSTALLED_LIBRARIES webpmux)
+  configure_pkg_config("src/mux/libwebpmux.pc")
+endif()
+
+if(WEBP_BUILD_GIF2WEBP)
+  # gif2webp
+  include_directories(${WEBP_DEP_GIF_INCLUDE_DIRS})
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "GIF2WEBP_SRCS"
+                    "gif2webp")
+  add_executable(gif2webp ${GIF2WEBP_SRCS})
+  target_link_libraries(gif2webp
+                        exampleutil
+                        imageioutil
+                        webp
+                        webpmux
+                        ${WEBP_DEP_GIF_LIBRARIES})
+  target_include_directories(gif2webp PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+  install(TARGETS gif2webp RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+endif()
+
+if(WEBP_BUILD_IMG2WEBP)
+  # img2webp
+  include_directories(${WEBP_DEP_IMG_INCLUDE_DIRS})
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "IMG2WEBP_SRCS"
+                    "img2webp")
+  add_executable(img2webp ${IMG2WEBP_SRCS})
+  target_link_libraries(img2webp
+                        exampleutil
+                        imagedec
+                        imageioutil
+                        webp
+                        webpmux)
+  target_include_directories(img2webp PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+  install(TARGETS img2webp RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+endif()
+
+if(WEBP_BUILD_VWEBP)
+  # vwebp
+  find_package(GLUT)
+  if(GLUT_FOUND)
+    include_directories(${WEBP_DEP_IMG_INCLUDE_DIRS})
+    parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "VWEBP_SRCS" "vwebp")
+    add_executable(vwebp ${VWEBP_SRCS})
+    target_link_libraries(vwebp
+                          ${OPENGL_LIBRARIES}
+                          exampleutil
+                          ${GLUT_glut_LIBRARY}
+                          imageioutil
+                          webp
+                          webpdemux)
+    target_include_directories(vwebp
+                               PRIVATE ${GLUT_INCLUDE_DIR}
+                                       ${CMAKE_CURRENT_BINARY_DIR}/src
+                                       ${OPENGL_INCLUDE_DIR})
+    install(TARGETS vwebp RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+    if(${CMAKE_SYSTEM_NAME} STREQUAL "Darwin")
+      check_c_compiler_flag("-Wno-deprecated-declarations" HAS_NO_DEPRECATED)
+      if(HAS_NO_DEPRECATED)
+        target_compile_options(vwebp PRIVATE "-Wno-deprecated-declarations")
+      endif()
+    endif()
+  endif()
+endif()
+
+if(WEBP_BUILD_WEBPINFO)
+  # webpinfo
+  include_directories(${WEBP_DEP_IMG_INCLUDE_DIRS})
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "WEBPINFO_SRCS"
+                    "webpinfo")
+  add_executable(webpinfo ${WEBPINFO_SRCS})
+  target_link_libraries(webpinfo exampleutil imageioutil)
+  target_include_directories(webpinfo
+                             PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src
+                                     ${CMAKE_CURRENT_SOURCE_DIR}/src)
+  install(TARGETS webpinfo RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+endif()
+
+if(WEBP_BUILD_WEBPMUX)
+  # webpmux
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "WEBPMUX_SRCS"
+                    "webpmux")
+  add_executable(webpmux_app ${WEBPMUX_SRCS})
+  set_target_properties(webpmux_app PROPERTIES OUTPUT_NAME webpmux)
+  target_link_libraries(webpmux_app exampleutil imageioutil webpmux webp)
+  target_include_directories(webpmux_app
+                             PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+  install(TARGETS webpmux_app RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+endif()
+
+if(WEBP_BUILD_EXTRAS)
+  set(EXTRAS_MAKEFILE "${CMAKE_CURRENT_SOURCE_DIR}/extras")
+  parse_makefile_am(${EXTRAS_MAKEFILE} "WEBP_EXTRAS_SRCS" "libwebpextras_la")
+  parse_makefile_am(${EXTRAS_MAKEFILE} "GET_DISTO_SRCS" "get_disto")
+  parse_makefile_am(${EXTRAS_MAKEFILE} "WEBP_QUALITY_SRCS" "webp_quality")
+  parse_makefile_am(${EXTRAS_MAKEFILE} "VWEBP_SDL_SRCS" "vwebp_sdl")
+
+  # libextras
+  add_library(extras STATIC ${WEBP_EXTRAS_SRCS})
+  target_include_directories(extras
+                             PRIVATE ${CMAKE_CURRENT_BINARY_DIR}
+                             ${CMAKE_CURRENT_SOURCE_DIR}
+                             ${CMAKE_CURRENT_SOURCE_DIR}/src)
+
+  # get_disto
+  add_executable(get_disto ${GET_DISTO_SRCS})
+  target_link_libraries(get_disto imagedec)
+  target_include_directories(get_disto
+                             PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+                                     ${CMAKE_CURRENT_BINARY_DIR}/src)
+
+  # webp_quality
+  add_executable(webp_quality ${WEBP_QUALITY_SRCS})
+  target_link_libraries(webp_quality exampleutil imagedec extras)
+  target_include_directories(webp_quality
+                             PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+                                     ${CMAKE_CURRENT_BINARY_DIR})
+
+  # vwebp_sdl
+  find_package(SDL)
+  if(WEBP_BUILD_VWEBP AND SDL_FOUND)
+    add_executable(vwebp_sdl ${VWEBP_SDL_SRCS})
+    target_link_libraries(vwebp_sdl ${SDL_LIBRARY} imageioutil webp)
+    target_include_directories(vwebp_sdl
+                               PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}
+                                       ${CMAKE_CURRENT_BINARY_DIR}
+                                       ${CMAKE_CURRENT_BINARY_DIR}/src
+                                       ${SDL_INCLUDE_DIR})
+    set(WEBP_HAVE_SDL 1)
+    target_compile_definitions(vwebp_sdl PUBLIC WEBP_HAVE_SDL)
+  endif()
+endif()
+
+if(WEBP_BUILD_WEBP_JS)
+  # wasm2js does not support SIMD.
+  if(NOT WEBP_ENABLE_SIMD)
+    # JavaScript version
+    add_executable(webp_js ${CMAKE_CURRENT_SOURCE_DIR}/extras/webp_to_sdl.c)
+    target_link_libraries(webp_js webpdecoder SDL)
+    target_include_directories(webp_js PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
+    set(WEBP_HAVE_SDL 1)
+    set_target_properties(
+      webp_js
+      PROPERTIES LINK_FLAGS "-s WASM=0 \
+         -s EXPORTED_FUNCTIONS='[\"_WebpToSDL\"]' -s INVOKE_RUN=0 \
+         -s EXPORTED_RUNTIME_METHODS='[\"cwrap\"]'")
+    set_target_properties(webp_js PROPERTIES OUTPUT_NAME webp)
+    target_compile_definitions(webp_js PUBLIC EMSCRIPTEN WEBP_HAVE_SDL)
+  endif()
+
+  # WASM version
+  add_executable(webp_wasm ${CMAKE_CURRENT_SOURCE_DIR}/extras/webp_to_sdl.c)
+  target_link_libraries(webp_wasm webpdecoder SDL)
+  target_include_directories(webp_wasm PRIVATE ${CMAKE_CURRENT_BINARY_DIR})
+  set_target_properties(
+    webp_wasm
+    PROPERTIES LINK_FLAGS "-s WASM=1 \
+       -s EXPORTED_FUNCTIONS='[\"_WebpToSDL\"]' -s INVOKE_RUN=0 \
+       -s EXPORTED_RUNTIME_METHODS='[\"cwrap\"]'")
+  target_compile_definitions(webp_wasm PUBLIC EMSCRIPTEN WEBP_HAVE_SDL)
+
+  target_compile_definitions(webpdspdecode PUBLIC EMSCRIPTEN)
+endif()
+
+if(WEBP_BUILD_ANIM_UTILS)
+  # anim_diff
+  include_directories(${WEBP_DEP_IMG_INCLUDE_DIRS} ${WEBP_DEP_GIF_INCLUDE_DIRS})
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "ANIM_DIFF_SRCS"
+                    "anim_diff")
+  add_executable(anim_diff ${ANIM_DIFF_SRCS})
+  target_link_libraries(anim_diff
+                        exampleutil
+                        imagedec
+                        imageenc
+                        imageioutil
+                        webp
+                        webpdemux
+                        ${WEBP_DEP_GIF_LIBRARIES})
+  target_include_directories(anim_diff PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+
+  # anim_dump
+  include_directories(${WEBP_DEP_IMG_INCLUDE_DIRS} ${WEBP_DEP_GIF_INCLUDE_DIRS})
+  parse_makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/examples "ANIM_DUMP_SRCS"
+                    "anim_dump")
+  add_executable(anim_dump ${ANIM_DUMP_SRCS})
+  target_link_libraries(anim_dump
+                        exampleutil
+                        imagedec
+                        imageenc
+                        imageioutil
+                        webp
+                        webpdemux
+                        ${WEBP_DEP_GIF_LIBRARIES})
+  target_include_directories(anim_dump PRIVATE ${CMAKE_CURRENT_BINARY_DIR}/src)
+endif()
+
+# Install the different headers and libraries.
+install(TARGETS ${INSTALLED_LIBRARIES}
+        EXPORT ${PROJECT_NAME}Targets
+        PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/webp
+        INCLUDES
+        DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+        ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
+set(ConfigPackageLocation ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME}/cmake/)
+install(EXPORT ${PROJECT_NAME}Targets
+        NAMESPACE ${PROJECT_NAME}::
+        DESTINATION ${ConfigPackageLocation})
+
+# Create the CMake version file.
+include(CMakePackageConfigHelpers)
+write_basic_package_version_file(
+  "${CMAKE_CURRENT_BINARY_DIR}/WebPConfigVersion.cmake"
+  VERSION ${PACKAGE_VERSION}
+  COMPATIBILITY AnyNewerVersion)
+
+# Create the Config file.
+include(CMakePackageConfigHelpers)
+configure_package_config_file(
+  ${CMAKE_CURRENT_SOURCE_DIR}/cmake/WebPConfig.cmake.in
+  ${CMAKE_CURRENT_BINARY_DIR}/WebPConfig.cmake
+  INSTALL_DESTINATION
+  ${ConfigPackageLocation})
+
+# Install the generated CMake files.
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/WebPConfigVersion.cmake"
+              "${CMAKE_CURRENT_BINARY_DIR}/WebPConfig.cmake"
+        DESTINATION ${ConfigPackageLocation})
+
+# Install the man pages.
+set(MAN_PAGES
+    cwebp.1
+    dwebp.1
+    gif2webp.1
+    img2webp.1
+    vwebp.1
+    webpmux.1
+    webpinfo.1)
+set(EXEC_BUILDS
+    "CWEBP"
+    "DWEBP"
+    "GIF2WEBP"
+    "IMG2WEBP"
+    "VWEBP"
+    "WEBPMUX"
+    "WEBPINFO")
+list(LENGTH MAN_PAGES MAN_PAGES_LENGTH)
+math(EXPR MAN_PAGES_RANGE "${MAN_PAGES_LENGTH} - 1")
+
+foreach(I_MAN RANGE ${MAN_PAGES_RANGE})
+  list(GET EXEC_BUILDS ${I_MAN} EXEC_BUILD)
+  if(WEBP_BUILD_${EXEC_BUILD})
+    list(GET MAN_PAGES ${I_MAN} MAN_PAGE)
+    install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/man/${MAN_PAGE}
+            DESTINATION ${CMAKE_INSTALL_MANDIR}/man1
+            COMPONENT doc)
+  endif()
+endforeach()

CONTRIBUTING.md

@@ -0,0 +1,29 @@
+# How to Contribute
+
+We'd love to accept your patches and contributions to this project. There are
+just a few small guidelines you need to follow.
+
+## Contributor License Agreement
+
+Contributions to this project must be accompanied by a Contributor License
+Agreement. You (or your employer) retain the copyright to your contribution;
+this simply gives us permission to use and redistribute your contributions as
+part of the project. Head over to <https://cla.developers.google.com/> to see
+your current agreements on file or to sign a new one.
+
+You generally only need to submit a CLA once, so if you've already submitted one
+(even if it was for a different project), you probably don't need to do it
+again.
+
+## Code reviews
+
+All submissions, including submissions by project members, require review. We
+use a [Gerrit](https://www.gerritcodereview.com) instance hosted at
+https://chromium-review.googlesource.com for this purpose. See the
+[WebM Project page](https://www.webmproject.org/code/contribute/submitting-patches/)
+for additional details.
+
+## Community Guidelines
+
+This project follows
+[Google's Open Source Community Guidelines](https://opensource.google.com/conduct/).

Makefile.am

@@ -1,3 +1,9 @@
 ACLOCAL_AMFLAGS = -I m4
-SUBDIRS = src examples man
+SUBDIRS = sharpyuv src imageio man
 EXTRA_DIST = COPYING autogen.sh
+
+if BUILD_EXTRAS
+  SUBDIRS += extras
+endif
+
+SUBDIRS += examples

Makefile.vc

@@ -11,6 +11,8 @@ LIBWEBPDEMUX_BASENAME = libwebpdemux
 ARCH = x86
 !ELSE IF ! [ cl 2>&1 | find "x64" > NUL ]
 ARCH = x64
+!ELSE IF ! [ cl 2>&1 | find "ARM" > NUL ]
+ARCH = ARM
 !ELSE
 !ERROR Unable to auto-detect toolchain architecture! \
 If cl.exe is in your PATH rerun nmake with ARCH=<arch>.
@@ -26,16 +28,22 @@ PLATFORM_LDFLAGS = /SAFESEH
 
 NOLOGO     = /nologo
 CCNODBG    = cl.exe $(NOLOGO) /O2 /DNDEBUG
-CCDEBUG    = cl.exe $(NOLOGO) /Od /Gm /Zi /D_DEBUG /RTC1
-CFLAGS     = /Isrc $(NOLOGO) /W3 /EHsc /c /GS
+CCDEBUG    = cl.exe $(NOLOGO) /Od /Zi /D_DEBUG /RTC1
+CFLAGS     = /I. /Isrc $(NOLOGO) /W3 /EHsc /c
 CFLAGS     = $(CFLAGS) /DWIN32 /D_CRT_SECURE_NO_WARNINGS /DWIN32_LEAN_AND_MEAN
-CFLAGS     = $(CFLAGS) /DHAVE_WINCODEC_H /DWEBP_USE_THREAD
-LDFLAGS    = /LARGEADDRESSAWARE /MANIFEST /NXCOMPAT /DYNAMICBASE
+LDFLAGS    = /LARGEADDRESSAWARE /MANIFEST:EMBED /NXCOMPAT /DYNAMICBASE
 LDFLAGS    = $(LDFLAGS) $(PLATFORM_LDFLAGS)
 LNKDLL     = link.exe /DLL $(NOLOGO)
 LNKEXE     = link.exe $(NOLOGO)
 LNKLIB     = lib.exe $(NOLOGO)
-MT         = mt.exe $(NOLOGO)
+RCNODBG    = rc.exe $(NOLOGO) /l"0x0409"  # 0x409 = U.S. English
+RCDEBUG    = $(RCNODBG) /D_DEBUG
+
+!IF "$(ARCH)" == "ARM"
+CFLAGS = $(CFLAGS) /DWINAPI_FAMILY=WINAPI_FAMILY_PHONE_APP /DWEBP_USE_THREAD
+!ELSE
+CFLAGS = $(CFLAGS) /DHAVE_WINCODEC_H /DWEBP_USE_THREAD
+!ENDIF
 
 CFGSET     = FALSE
 !IF "$(OBJDIR)" == ""
@@ -49,6 +57,11 @@ OUTDIR = $(OBJDIR)
 !IF "$(RTLIBCFG)" == "static"
 RTLIB  = /MT
 RTLIBD = /MTd
+!ELSE IF "$(RTLIBCFG)" == "legacy"
+RTLIBCFG = static
+RTLIB  = /MT
+RTLIBD = /MTd
+CFLAGS = $(CFLAGS) /GS- /arch:IA32
 !ELSE
 RTLIB   = /MD
 RTLIBD  = /MDd
@@ -65,7 +78,10 @@ OUTPUT_DIRS = $(DIRBIN) $(DIRINC) $(DIRLIB) \
               $(DIROBJ)\dsp \
               $(DIROBJ)\enc \
               $(DIROBJ)\examples \
+              $(DIROBJ)\extras \
+              $(DIROBJ)\imageio \
               $(DIROBJ)\mux \
+              $(DIROBJ)\sharpyuv \
               $(DIROBJ)\utils \
 
 # Target configuration
@@ -82,9 +98,11 @@ LIBWEBPMUX_BASENAME = $(LIBWEBPMUX_BASENAME)_debug
 LIBWEBPDEMUX_BASENAME = $(LIBWEBPDEMUX_BASENAME)_debug
 !ELSE IF "$(CFG)" == "release-dynamic"
 CC        = $(CCNODBG)
+RC        = $(RCNODBG)
 DLLBUILD  = TRUE
 !ELSE IF "$(CFG)" == "debug-dynamic"
 CC        = $(CCDEBUG)
+RC        = $(RCDEBUG)
 RTLIB     = $(RTLIBD)
 DLLBUILD  = TRUE
 LIBWEBPDECODER_BASENAME = $(LIBWEBPDECODER_BASENAME)_debug
@@ -101,9 +119,7 @@ LIBWEBP = $(DIRLIB)\$(LIBWEBP_BASENAME).lib
 LIBWEBPMUX = $(DIRLIB)\$(LIBWEBPMUX_BASENAME).lib
 LIBWEBPDEMUX = $(DIRLIB)\$(LIBWEBPDEMUX_BASENAME).lib
 !ELSE IF "$(DLLBUILD)" == "TRUE"
-DLLC   = webp_dll.c
 DLLINC = webp_dll.h
-DLL_OBJS = $(DIROBJ)\$(DLLC:.c=.obj)
 CC     = $(CC) /I$(DIROBJ) /FI$(DLLINC) $(RTLIB) /DWEBP_DLL
 LIBWEBPDECODER = $(DIRLIB)\$(LIBWEBPDECODER_BASENAME)_dll.lib
 LIBWEBP = $(DIRLIB)\$(LIBWEBP_BASENAME)_dll.lib
@@ -113,12 +129,16 @@ LIBWEBP_PDBNAME = $(DIROBJ)\$(LIBWEBP_BASENAME)_dll.pdb
 CFGSET = TRUE
 !ENDIF
 
+!IF "$(UNICODE)" == "1"
+CFLAGS = $(CFLAGS) /D_UNICODE /DUNICODE
+!ENDIF
+
 #######################
 # Usage
 #
 !IF "$(CFGSET)" == "FALSE"
 !MESSAGE Usage: nmake /f Makefile.vc [CFG=<config>]
-!MESSAGE .          [OBJDIR=<path>] [RTLIBCFG=<rtlib>] [<target>]
+!MESSAGE .          [OBJDIR=<path>] [RTLIBCFG=<rtlib>] [UNICODE=1] [<target>]
 !MESSAGE
 !MESSAGE where <config> is one of:
 !MESSAGE -  release-static                - release static library
@@ -132,8 +152,12 @@ CFGSET = TRUE
 !MESSAGE .                                  features enabled.
 !MESSAGE - (empty)                        - build libwebp-based targets for CFG
 !MESSAGE - all                            - build (de)mux-based targets for CFG
+!MESSAGE - gif2webp                       - requires libgif & >= VS2013
+!MESSAGE - anim_diff                      - requires libgif & >= VS2013
+!MESSAGE - anim_dump
 !MESSAGE
 !MESSAGE RTLIBCFG controls the runtime library linkage - 'static' or 'dynamic'.
+!MESSAGE   'legacy' will produce a Windows 2000 compatible library.
 !MESSAGE OBJDIR is the path where you like to build (obj, bins, etc.),
 !MESSAGE   defaults to ..\obj
 
@@ -150,114 +174,248 @@ CFGSET = TRUE
 # A config was provided, so the library can be built.
 #
 
+SHARPYUV_OBJS = \
+    $(DIROBJ)\sharpyuv\sharpyuv.obj \
+    $(DIROBJ)\sharpyuv\sharpyuv_csp.obj \
+    $(DIROBJ)\sharpyuv\sharpyuv_dsp.obj \
+    $(DIROBJ)\sharpyuv\sharpyuv_gamma.obj \
+    $(DIROBJ)\sharpyuv\sharpyuv_neon.obj \
+    $(DIROBJ)\sharpyuv\sharpyuv_sse2.obj \
+
 DEC_OBJS = \
-    $(DIROBJ)\dec\alpha.obj \
-    $(DIROBJ)\dec\buffer.obj \
-    $(DIROBJ)\dec\frame.obj \
-    $(DIROBJ)\dec\idec.obj \
-    $(DIROBJ)\dec\io.obj \
-    $(DIROBJ)\dec\layer.obj \
-    $(DIROBJ)\dec\quant.obj \
-    $(DIROBJ)\dec\tree.obj \
-    $(DIROBJ)\dec\vp8.obj \
-    $(DIROBJ)\dec\vp8l.obj \
-    $(DIROBJ)\dec\webp.obj \
+    $(DIROBJ)\dec\alpha_dec.obj \
+    $(DIROBJ)\dec\buffer_dec.obj \
+    $(DIROBJ)\dec\frame_dec.obj \
+    $(DIROBJ)\dec\idec_dec.obj \
+    $(DIROBJ)\dec\io_dec.obj \
+    $(DIROBJ)\dec\quant_dec.obj \
+    $(DIROBJ)\dec\tree_dec.obj \
+    $(DIROBJ)\dec\vp8_dec.obj \
+    $(DIROBJ)\dec\vp8l_dec.obj \
+    $(DIROBJ)\dec\webp_dec.obj \
 
 DEMUX_OBJS = \
+    $(DIROBJ)\demux\anim_decode.obj \
     $(DIROBJ)\demux\demux.obj \
 
 DSP_DEC_OBJS = \
+    $(DIROBJ)\dsp\alpha_processing.obj \
+    $(DIROBJ)\dsp\alpha_processing_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\alpha_processing_neon.obj \
+    $(DIROBJ)\dsp\alpha_processing_sse2.obj \
+    $(DIROBJ)\dsp\alpha_processing_sse41.obj \
     $(DIROBJ)\dsp\cpu.obj \
     $(DIROBJ)\dsp\dec.obj \
+    $(DIROBJ)\dsp\dec_clip_tables.obj \
+    $(DIROBJ)\dsp\dec_mips32.obj \
+    $(DIROBJ)\dsp\dec_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\dec_msa.obj \
     $(DIROBJ)\dsp\dec_neon.obj \
     $(DIROBJ)\dsp\dec_sse2.obj \
+    $(DIROBJ)\dsp\dec_sse41.obj \
+    $(DIROBJ)\dsp\filters.obj \
+    $(DIROBJ)\dsp\filters_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\filters_msa.obj \
+    $(DIROBJ)\dsp\filters_neon.obj \
+    $(DIROBJ)\dsp\filters_sse2.obj \
     $(DIROBJ)\dsp\lossless.obj \
+    $(DIROBJ)\dsp\lossless_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\lossless_msa.obj \
+    $(DIROBJ)\dsp\lossless_neon.obj \
+    $(DIROBJ)\dsp\lossless_sse2.obj \
+    $(DIROBJ)\dsp\lossless_sse41.obj \
+    $(DIROBJ)\dsp\rescaler.obj \
+    $(DIROBJ)\dsp\rescaler_mips32.obj \
+    $(DIROBJ)\dsp\rescaler_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\rescaler_msa.obj \
+    $(DIROBJ)\dsp\rescaler_neon.obj \
+    $(DIROBJ)\dsp\rescaler_sse2.obj \
     $(DIROBJ)\dsp\upsampling.obj \
+    $(DIROBJ)\dsp\upsampling_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\upsampling_msa.obj \
     $(DIROBJ)\dsp\upsampling_neon.obj \
     $(DIROBJ)\dsp\upsampling_sse2.obj \
+    $(DIROBJ)\dsp\upsampling_sse41.obj \
     $(DIROBJ)\dsp\yuv.obj \
+    $(DIROBJ)\dsp\yuv_mips32.obj \
+    $(DIROBJ)\dsp\yuv_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\yuv_neon.obj \
+    $(DIROBJ)\dsp\yuv_sse2.obj \
+    $(DIROBJ)\dsp\yuv_sse41.obj \
 
 DSP_ENC_OBJS = \
+    $(DIROBJ)\dsp\cost.obj \
+    $(DIROBJ)\dsp\cost_mips32.obj \
+    $(DIROBJ)\dsp\cost_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\cost_neon.obj \
+    $(DIROBJ)\dsp\cost_sse2.obj \
     $(DIROBJ)\dsp\enc.obj \
+    $(DIROBJ)\dsp\enc_mips32.obj \
+    $(DIROBJ)\dsp\enc_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\enc_msa.obj \
     $(DIROBJ)\dsp\enc_neon.obj \
     $(DIROBJ)\dsp\enc_sse2.obj \
+    $(DIROBJ)\dsp\enc_sse41.obj \
+    $(DIROBJ)\dsp\lossless_enc.obj \
+    $(DIROBJ)\dsp\lossless_enc_mips32.obj \
+    $(DIROBJ)\dsp\lossless_enc_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\lossless_enc_msa.obj \
+    $(DIROBJ)\dsp\lossless_enc_neon.obj \
+    $(DIROBJ)\dsp\lossless_enc_sse2.obj \
+    $(DIROBJ)\dsp\lossless_enc_sse41.obj \
+    $(DIROBJ)\dsp\ssim.obj \
+    $(DIROBJ)\dsp\ssim_sse2.obj \
 
-EX_FORMAT_DEC_OBJS = \
-    $(DIROBJ)\examples\jpegdec.obj \
-    $(DIROBJ)\examples\metadata.obj \
-    $(DIROBJ)\examples\pngdec.obj \
-    $(DIROBJ)\examples\tiffdec.obj \
-    $(DIROBJ)\examples\wicdec.obj \
+EX_ANIM_UTIL_OBJS = \
+    $(DIROBJ)\examples\anim_util.obj \
+
+IMAGEIO_DEC_OBJS = \
+    $(DIROBJ)\imageio\image_dec.obj \
+    $(DIROBJ)\imageio\jpegdec.obj \
+    $(DIROBJ)\imageio\metadata.obj \
+    $(DIROBJ)\imageio\pngdec.obj \
+    $(DIROBJ)\imageio\pnmdec.obj \
+    $(DIROBJ)\imageio\tiffdec.obj \
+    $(DIROBJ)\imageio\webpdec.obj \
+    $(DIROBJ)\imageio\wicdec.obj \
+
+IMAGEIO_ENC_OBJS = \
+    $(DIROBJ)\imageio\image_enc.obj \
+
+EX_GIF_DEC_OBJS = \
+    $(DIROBJ)\examples\gifdec.obj \
 
 EX_UTIL_OBJS = \
     $(DIROBJ)\examples\example_util.obj \
 
 ENC_OBJS = \
-    $(DIROBJ)\enc\alpha.obj \
-    $(DIROBJ)\enc\analysis.obj \
-    $(DIROBJ)\enc\backward_references.obj \
-    $(DIROBJ)\enc\config.obj \
-    $(DIROBJ)\enc\cost.obj \
-    $(DIROBJ)\enc\filter.obj \
-    $(DIROBJ)\enc\frame.obj \
-    $(DIROBJ)\enc\histogram.obj \
-    $(DIROBJ)\enc\iterator.obj \
-    $(DIROBJ)\enc\layer.obj \
-    $(DIROBJ)\enc\picture.obj \
-    $(DIROBJ)\enc\quant.obj \
-    $(DIROBJ)\enc\syntax.obj \
-    $(DIROBJ)\enc\token.obj \
-    $(DIROBJ)\enc\tree.obj \
-    $(DIROBJ)\enc\vp8l.obj \
-    $(DIROBJ)\enc\webpenc.obj \
+    $(DIROBJ)\enc\alpha_enc.obj \
+    $(DIROBJ)\enc\analysis_enc.obj \
+    $(DIROBJ)\enc\backward_references_cost_enc.obj \
+    $(DIROBJ)\enc\backward_references_enc.obj \
+    $(DIROBJ)\enc\config_enc.obj \
+    $(DIROBJ)\enc\cost_enc.obj \
+    $(DIROBJ)\enc\filter_enc.obj \
+    $(DIROBJ)\enc\frame_enc.obj \
+    $(DIROBJ)\enc\histogram_enc.obj \
+    $(DIROBJ)\enc\iterator_enc.obj \
+    $(DIROBJ)\enc\near_lossless_enc.obj \
+    $(DIROBJ)\enc\picture_enc.obj \
+    $(DIROBJ)\enc\picture_csp_enc.obj \
+    $(DIROBJ)\enc\picture_psnr_enc.obj \
+    $(DIROBJ)\enc\picture_rescale_enc.obj \
+    $(DIROBJ)\enc\picture_tools_enc.obj \
+    $(DIROBJ)\enc\predictor_enc.obj \
+    $(DIROBJ)\enc\quant_enc.obj \
+    $(DIROBJ)\enc\syntax_enc.obj \
+    $(DIROBJ)\enc\token_enc.obj \
+    $(DIROBJ)\enc\tree_enc.obj \
+    $(DIROBJ)\enc\vp8l_enc.obj \
+    $(DIROBJ)\enc\webp_enc.obj \
+
+EXTRAS_OBJS = \
+    $(DIROBJ)\extras\extras.obj \
+    $(DIROBJ)\extras\quality_estimate.obj \
+
+IMAGEIO_UTIL_OBJS = \
+    $(DIROBJ)\imageio\imageio_util.obj \
 
 MUX_OBJS = \
+    $(DIROBJ)\mux\anim_encode.obj \
     $(DIROBJ)\mux\muxedit.obj \
     $(DIROBJ)\mux\muxinternal.obj \
     $(DIROBJ)\mux\muxread.obj \
 
 UTILS_DEC_OBJS = \
-    $(DIROBJ)\utils\alpha_processing.obj \
-    $(DIROBJ)\utils\bit_reader.obj \
-    $(DIROBJ)\utils\color_cache.obj \
-    $(DIROBJ)\utils\filters.obj \
-    $(DIROBJ)\utils\huffman.obj \
-    $(DIROBJ)\utils\quant_levels_dec.obj \
-    $(DIROBJ)\utils\rescaler.obj \
-    $(DIROBJ)\utils\random.obj \
-    $(DIROBJ)\utils\thread.obj \
+    $(DIROBJ)\utils\bit_reader_utils.obj \
+    $(DIROBJ)\utils\color_cache_utils.obj \
+    $(DIROBJ)\utils\filters_utils.obj \
+    $(DIROBJ)\utils\huffman_utils.obj \
+    $(DIROBJ)\utils\quant_levels_dec_utils.obj \
+    $(DIROBJ)\utils\rescaler_utils.obj \
+    $(DIROBJ)\utils\random_utils.obj \
+    $(DIROBJ)\utils\thread_utils.obj \
     $(DIROBJ)\utils\utils.obj \
 
 UTILS_ENC_OBJS = \
-    $(DIROBJ)\utils\bit_writer.obj \
-    $(DIROBJ)\utils\huffman_encode.obj \
-    $(DIROBJ)\utils\quant_levels.obj \
+    $(DIROBJ)\utils\bit_writer_utils.obj \
+    $(DIROBJ)\utils\huffman_encode_utils.obj \
+    $(DIROBJ)\utils\quant_levels_utils.obj \
 
 LIBWEBPDECODER_OBJS = $(DEC_OBJS) $(DSP_DEC_OBJS) $(UTILS_DEC_OBJS)
-LIBWEBP_OBJS = $(LIBWEBPDECODER_OBJS) $(ENC_OBJS) $(DSP_ENC_OBJS) \
-               $(UTILS_ENC_OBJS) $(DLL_OBJS)
+LIBWEBP_OBJS = $(LIBWEBPDECODER_OBJS) $(SHARPYUV_OBJS) $(ENC_OBJS) \
+               $(DSP_ENC_OBJS) $(UTILS_ENC_OBJS) $(DLL_OBJS)
 LIBWEBPMUX_OBJS = $(MUX_OBJS) $(LIBWEBPMUX_OBJS)
 LIBWEBPDEMUX_OBJS = $(DEMUX_OBJS) $(LIBWEBPDEMUX_OBJS)
 
 OUT_LIBS = $(LIBWEBPDECODER) $(LIBWEBP)
+!IF "$(ARCH)" == "ARM"
+ex: $(OUT_LIBS)
+all: ex
+!ELSE
 OUT_EXAMPLES = $(DIRBIN)\cwebp.exe $(DIRBIN)\dwebp.exe
-EXTRA_EXAMPLES = $(DIRBIN)\vwebp.exe $(DIRBIN)\webpmux.exe
+EXTRA_EXAMPLES = $(DIRBIN)\vwebp.exe $(DIRBIN)\webpmux.exe \
+                 $(DIRBIN)\img2webp.exe $(DIRBIN)\get_disto.exe \
+                 $(DIRBIN)\webp_quality.exe $(DIRBIN)\vwebp_sdl.exe \
+                 $(DIRBIN)\webpinfo.exe
 
 ex: $(OUT_LIBS) $(OUT_EXAMPLES)
 all: ex $(EXTRA_EXAMPLES)
-$(DIRBIN)\cwebp.exe: $(DIROBJ)\examples\cwebp.obj $(EX_FORMAT_DEC_OBJS)
-$(DIRBIN)\dwebp.exe: $(DIROBJ)\examples\dwebp.obj
-$(DIRBIN)\vwebp.exe: $(DIROBJ)\examples\vwebp.obj
-$(DIRBIN)\vwebp.exe: $(EX_UTIL_OBJS) $(LIBWEBPDEMUX) $(LIBWEBP)
-$(DIRBIN)\webpmux.exe: $(DIROBJ)\examples\webpmux.obj $(LIBWEBPMUX)
-$(DIRBIN)\webpmux.exe: $(EX_UTIL_OBJS) $(LIBWEBP)
-$(OUT_EXAMPLES): $(EX_UTIL_OBJS) $(LIBWEBP)
-$(EX_UTIL_OBJS) $(EX_FORMAT_DEC_OBJS): $(OUTPUT_DIRS)
+# NB: gif2webp.exe and anim_diff.exe are excluded from 'all' as libgif requires
+# C99 support which is only available from VS2013 onward.
+gif2webp: $(DIRBIN)\gif2webp.exe
+anim_diff: $(DIRBIN)\anim_diff.exe
+anim_dump: $(DIRBIN)\anim_dump.exe
 
-experimental:
-	$(MAKE) /f Makefile.vc \
-	    CFG=$(CFG) \
-	    CFLAGS="$(CFLAGS) /DWEBP_EXPERIMENTAL_FEATURES" /$(MAKEFLAGS)
+$(DIRBIN)\anim_diff.exe: $(DIROBJ)\examples\anim_diff.obj $(EX_ANIM_UTIL_OBJS)
+$(DIRBIN)\anim_diff.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\anim_diff.exe: $(EX_GIF_DEC_OBJS) $(LIBWEBPDEMUX) $(LIBWEBP)
+$(DIRBIN)\anim_dump.exe: $(DIROBJ)\examples\anim_dump.obj $(EX_ANIM_UTIL_OBJS)
+$(DIRBIN)\anim_dump.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\anim_dump.exe: $(EX_GIF_DEC_OBJS) $(LIBWEBPDEMUX) $(LIBWEBP)
+$(DIRBIN)\anim_dump.exe: $(IMAGEIO_ENC_OBJS)
+$(DIRBIN)\cwebp.exe: $(DIROBJ)\examples\cwebp.obj $(IMAGEIO_DEC_OBJS)
+$(DIRBIN)\cwebp.exe: $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\cwebp.exe: $(LIBWEBPDEMUX)
+$(DIRBIN)\dwebp.exe: $(DIROBJ)\examples\dwebp.obj $(IMAGEIO_DEC_OBJS)
+$(DIRBIN)\dwebp.exe: $(IMAGEIO_ENC_OBJS)
+$(DIRBIN)\dwebp.exe: $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\dwebp.exe: $(LIBWEBPDEMUX)
+$(DIRBIN)\gif2webp.exe: $(DIROBJ)\examples\gif2webp.obj $(EX_GIF_DEC_OBJS)
+$(DIRBIN)\gif2webp.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS) $(LIBWEBPMUX)
+$(DIRBIN)\gif2webp.exe: $(LIBWEBP)
+$(DIRBIN)\vwebp.exe: $(DIROBJ)\examples\vwebp.obj $(EX_UTIL_OBJS)
+$(DIRBIN)\vwebp.exe: $(IMAGEIO_UTIL_OBJS) $(LIBWEBPDEMUX) $(LIBWEBP)
+$(DIRBIN)\vwebp_sdl.exe: $(DIROBJ)\extras\vwebp_sdl.obj
+$(DIRBIN)\vwebp_sdl.exe: $(DIROBJ)\extras\webp_to_sdl.obj
+$(DIRBIN)\vwebp_sdl.exe: $(IMAGEIO_UTIL_OBJS) $(LIBWEBP)
+$(DIRBIN)\webpmux.exe: $(DIROBJ)\examples\webpmux.obj $(LIBWEBPMUX)
+$(DIRBIN)\webpmux.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS) $(LIBWEBP)
+$(DIRBIN)\img2webp.exe: $(DIROBJ)\examples\img2webp.obj $(LIBWEBPMUX)
+$(DIRBIN)\img2webp.exe: $(IMAGEIO_DEC_OBJS)
+$(DIRBIN)\img2webp.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\img2webp.exe: $(LIBWEBPDEMUX) $(LIBWEBP)
+$(DIRBIN)\get_disto.exe: $(DIROBJ)\extras\get_disto.obj
+$(DIRBIN)\get_disto.exe: $(IMAGEIO_DEC_OBJS) $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\get_disto.exe: $(LIBWEBPDEMUX) $(LIBWEBP)
+$(DIRBIN)\webp_quality.exe: $(DIROBJ)\extras\webp_quality.obj
+$(DIRBIN)\webp_quality.exe: $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\webp_quality.exe: $(EXTRAS_OBJS)
+# EXTRA_OBJS requires private symbols from dsp. Explicitly add those when
+# building libwebp as a dll.
+!IF "$(DLLBUILD)" == "TRUE"
+$(DIRBIN)\webp_quality.exe: $(DSP_DEC_OBJS)
+!ENDIF
+$(DIRBIN)\webp_quality.exe: $(LIBWEBP)
+$(DIRBIN)\webpinfo.exe: $(DIROBJ)\examples\webpinfo.obj
+$(DIRBIN)\webpinfo.exe: $(IMAGEIO_DEC_OBJS)
+$(DIRBIN)\webpinfo.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS)
+$(DIRBIN)\webpinfo.exe: $(LIBWEBPDEMUX) $(LIBWEBP)
+
+$(OUT_EXAMPLES): $(EX_UTIL_OBJS) $(LIBWEBP)
+$(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS): $(OUTPUT_DIRS)
+$(IMAGEIO_DEC_OBJS) $(IMAGEIO_ENC_OBJS) $(EXTRAS_OBJS): $(OUTPUT_DIRS)
+!ENDIF  # ARCH == ARM
 
 $(LIBWEBPDECODER): $(LIBWEBPDECODER_OBJS)
 $(LIBWEBP): $(LIBWEBP_OBJS)
@@ -268,20 +426,29 @@ $(LIBWEBP_OBJS) $(LIBWEBPMUX_OBJS) $(LIBWEBPDEMUX_OBJS): $(OUTPUT_DIRS)
 
 !IF "$(DLLBUILD)" == "TRUE"
 $(LIBWEBP_OBJS) $(LIBWEBPMUX_OBJS) $(LIBWEBPDEMUX_OBJS): \
-    $(DIROBJ)\$(DLLINC) $(DIROBJ)\$(DLLC)
+    $(DIROBJ)\$(DLLINC)
 
 {$(DIROBJ)}.c{$(DIROBJ)}.obj:
 	$(CC) $(CFLAGS) /Fd$(LIBWEBP_PDBNAME) /Fo$@  $<
 
-$(LIBWEBPMUX): $(LIBWEBP)
-$(LIBWEBPDEMUX): $(LIBWEBP)
+{src}.rc{$(DIROBJ)}.res:
+	$(RC) /fo$@ $<
+{src\demux}.rc{$(DIROBJ)\demux}.res:
+	$(RC) /fo$@ $<
+{src\mux}.rc{$(DIROBJ)\mux}.res:
+	$(RC) /fo$@ $<
+
+$(LIBWEBP): $(DIROBJ)\$(LIBWEBP_BASENAME:_debug=).res
+$(LIBWEBPDECODER): $(DIROBJ)\$(LIBWEBPDECODER_BASENAME:_debug=).res
+$(LIBWEBPMUX): $(LIBWEBP) $(DIROBJ)\mux\$(LIBWEBPMUX_BASENAME:_debug=).res
+$(LIBWEBPDEMUX): $(LIBWEBP) $(DIROBJ)\demux\$(LIBWEBPDEMUX_BASENAME:_debug=).res
 
 $(LIBWEBPDECODER) $(LIBWEBP) $(LIBWEBPMUX) $(LIBWEBPDEMUX):
 	$(LNKDLL) /out:$(DIRBIN)\$(@B:_dll=.dll) /implib:$@ $(LFLAGS) $**
 	-xcopy $(DIROBJ)\*.pdb $(DIRLIB) /y
 
 clean::
-	@-erase /s $(DIROBJ)\$(DLLC) $(DIROBJ)\$(DLLINC) 2> NUL
+	@-erase /s $(DIROBJ)\$(DLLINC) 2> NUL
 !ELSE
 $(LIBWEBPDECODER) $(LIBWEBP) $(LIBWEBPMUX) $(LIBWEBPDEMUX):
 	$(LNKLIB) /out:$@ $**
@@ -295,22 +462,36 @@ $(OUTPUT_DIRS):
 $(DIROBJ)\$(DLLINC):
 	@echo #ifndef WEBP_DLL_H_ > $@
 	@echo #define WEBP_DLL_H_ >> $@
-	@echo #define WEBP_EXTERN(type) __declspec(dllexport) type >> $@
+	@echo #define WEBP_EXTERN __declspec(dllexport) >> $@
 	@echo #endif  /* WEBP_DLL_H_ */ >> $@
 
-# expose a WebPFree() function for use in managed code
-$(DIROBJ)\$(DLLC): $(DIROBJ)\$(DLLINC)
-	@echo #include ^<stdlib.h^> > $@
-	@echo #include "webp_dll.h" >> $@
-	@echo // This function should be used in place of free() for memory >> $@
-	@echo // returned by the WebP API. >> $@
-	@echo WEBP_EXTERN(void) WebPFree(void* ptr) { >> $@
-	@echo   free(ptr); >> $@
-	@echo } >> $@
-
 .SUFFIXES: .c .obj .res .exe
+# File-specific flag builds. Note batch rules take precedence over wildcards,
+# so for now name each file individually.
+$(DIROBJ)\examples\anim_diff.obj: examples\anim_diff.c
+	$(CC) $(CFLAGS) /DWEBP_HAVE_GIF /Fd$(LIBWEBP_PDBNAME) \
+	  /Fo$(DIROBJ)\examples\ examples\$(@B).c
+$(DIROBJ)\examples\anim_dump.obj: examples\anim_dump.c
+	$(CC) $(CFLAGS) /DWEBP_HAVE_GIF /Fd$(LIBWEBP_PDBNAME) \
+	  /Fo$(DIROBJ)\examples\ examples\$(@B).c
+$(DIROBJ)\examples\anim_util.obj: examples\anim_util.c
+	$(CC) $(CFLAGS) /DWEBP_HAVE_GIF /Fd$(LIBWEBP_PDBNAME) \
+	  /Fo$(DIROBJ)\examples\ examples\$(@B).c
+$(DIROBJ)\examples\gif2webp.obj: examples\gif2webp.c
+	$(CC) $(CFLAGS) /DWEBP_HAVE_GIF /Fd$(LIBWEBP_PDBNAME) \
+	  /Fo$(DIROBJ)\examples\ examples\$(@B).c
+$(DIROBJ)\examples\gifdec.obj: examples\gifdec.c
+	$(CC) $(CFLAGS) /DWEBP_HAVE_GIF /Fd$(LIBWEBP_PDBNAME) \
+	  /Fo$(DIROBJ)\examples\ examples\$(@B).c
+# Batch rules
 {examples}.c{$(DIROBJ)\examples}.obj::
-	$(CC) $(CFLAGS) /Fd$(DIROBJ)\examples\ /Fo$(DIROBJ)\examples\  $<
+	$(CC) $(CFLAGS) /Fd$(DIROBJ)\examples\ /Fo$(DIROBJ)\examples\ $<
+{extras}.c{$(DIROBJ)\extras}.obj::
+	$(CC) $(CFLAGS) /Fd$(DIROBJ)\extras\ /Fo$(DIROBJ)\extras\ $<
+{imageio}.c{$(DIROBJ)\imageio}.obj::
+	$(CC) $(CFLAGS) /Fd$(DIROBJ)\imageio\ /Fo$(DIROBJ)\imageio\ $<
+{sharpyuv}.c{$(DIROBJ)\sharpyuv}.obj::
+	$(CC) $(CFLAGS) /Fd$(DIROBJ)\sharpyuv\ /Fo$(DIROBJ)\sharpyuv\ $<
 {src\dec}.c{$(DIROBJ)\dec}.obj::
 	$(CC) $(CFLAGS) /Fd$(LIBWEBP_PDBNAME) /Fo$(DIROBJ)\dec\ $<
 {src\demux}.c{$(DIROBJ)\demux}.obj::
@@ -324,11 +505,16 @@ $(DIROBJ)\$(DLLC): $(DIROBJ)\$(DLLINC)
 {src\utils}.c{$(DIROBJ)\utils}.obj::
 	$(CC) $(CFLAGS) /Fd$(LIBWEBP_PDBNAME) /Fo$(DIROBJ)\utils\ $<
 
+LNKLIBS     = ole32.lib windowscodecs.lib shlwapi.lib
+!IF "$(UNICODE)" == "1"
+LNKLIBS     = $(LNKLIBS) Shell32.lib
+!ENDIF
+
 {$(DIROBJ)\examples}.obj{$(DIRBIN)}.exe:
-	$(LNKEXE) $(LDFLAGS) /OUT:$@ $** \
-	    ole32.lib windowscodecs.lib shlwapi.lib
-	$(MT) -manifest $@.manifest -outputresource:$@;1
-	del $@.manifest
+	$(LNKEXE) $(LDFLAGS) /OUT:$@ $** $(LNKLIBS)
+
+{$(DIROBJ)\extras}.obj{$(DIRBIN)}.exe:
+	$(LNKEXE) $(LDFLAGS) /OUT:$@ $** $(LNKLIBS)
 
 clean::
 	@-erase /s $(DIROBJ)\*.dll 2> NUL

NEWS

@@ -1,3 +1,207 @@
+- 6/30/2022: version 1.2.3
+  This is a binary compatible release.
+  * security fix for lossless encoder (#565, chromium:1313709)
+  * improved progress granularity in WebPReportProgress() when using lossless
+  * improved precision in Sharp YUV (-sharp_yuv) conversion
+  * many corrections to webp-lossless-bitstream-spec.txt (#551)
+  * crash/leak fixes on error/OOM and other bug fixes (#558, #563, #569, #573)
+
+- 1/11/2022: version 1.2.2
+  This is a binary compatible release.
+  * webpmux: add "-set bgcolor A,R,G,B"
+  * add ARM64 NEON support for MSVC builds (#539)
+  * fix duplicate include error in Xcode when using multiple XCFrameworks in a
+    project (#542)
+  * doc updates and bug fixes (#538, #544, #548, #550)
+
+- 7/20/2021: version 1.2.1
+  This is a binary compatible release.
+  * minor lossless encoder improvements and x86 color conversion speed up
+  * add ARM64 simulator support to xcframeworkbuild.sh (#510)
+  * further security related hardening in libwebp & examples
+    (issues: #497, #508, #518)
+    (chromium: #1196480, #1196773, #1196775, #1196777, #1196778, #1196850)
+    (oss-fuzz: #28658, #28978)
+  * toolchain updates and bug fixes (#498, #501, #502, #504, #505, #506, #509,
+                                     #533)
+  * use more inclusive language within the source (#507)
+
+- 12/23/2020: version 1.2.0
+  * API changes:
+    - libwebp:
+      encode.h: add a qmin / qmax range for quality factor (cwebp adds -qrange)
+  * lossless encoder improvements
+  * SIMD support for Wasm builds
+  * add xcframeworkbuild.sh, supports Mac Catalyst builds
+  * import fuzzers from oss-fuzz & chromium (#409)
+  * webpmux: add an '-set loop <value>' option (#494)
+  * toolchain updates and bug fixes (#449, #463, #470, #475, #477, #478, #479,
+    #488, #491)
+
+- 12/18/2019: version 1.1.0
+  * API changes:
+    - libwebp:
+      WebPMalloc (issue #442)
+    - extras:
+      WebPUnmultiplyARGB
+  * alpha decode fix (issue #439)
+  * toolchain updates and bug fixes
+    (chromium: #1026858, #1027136, #1027409, #1028620, #1028716, #995200)
+    (oss-fuzz: #19430, #19447)
+
+- 7/4/2019: version 1.0.3
+  This is a binary compatible release.
+  * resize fixes for Nx1 sizes and the addition of non-opaque alpha values for
+    odd sizes (issues #418, #434)
+  * lossless encode/decode performance improvements
+  * lossy compression performance improvement at low quality levels with flat
+    content (issue #432)
+  * python swig files updated to support python 3
+  Tool updates:
+    vwebp will now preserve the aspect ratio of images that exceed monitor
+    resolution by scaling the image to fit (issue #433)
+
+- 1/14/2019: version 1.0.2
+  This is a binary compatible release.
+  * (Windows) unicode file support in the tools (linux and mac already had
+    support, issue #398)
+  * lossless encoder speedups
+  * lossy encoder speedup on ARM
+  * lossless multi-threaded security fix (chromium:917029)
+
+- 11/2/2018: version 1.0.1
+  This is a binary compatible release.
+  * lossless encoder speedups
+  * big-endian fix for alpha decoding (issue #393)
+  * gif2webp fix for loop count=65535 transcode (issue #382)
+  * further security related hardening in libwebp & libwebpmux
+    (issues #383, #385, #386, #387, #388, #391)
+    (oss-fuzz #9099, #9100, #9105, #9106, #9111, #9112, #9119, #9123, #9170,
+              #9178, #9179, #9183, #9186, #9191, #9364, #9417, #9496, #10349,
+              #10423, #10634, #10700, #10838, #10922, #11021, #11088, #11152)
+  * miscellaneous bug & build fixes (issues #381, #394, #396, #397, #400)
+
+- 4/2/2018: version 1.0.0
+  This is a binary compatible release.
+  * lossy encoder improvements to avoid chroma shifts in various circumstances
+    (issues #308, #340)
+  * big-endian fixes for decode, RGBA import and WebPPictureDistortion
+  Tool updates:
+    gifwebp, anim_diff - default duration behavior (<= 10ms) changed to match
+                         web browsers, transcoding tools (issue #379)
+    img2webp, webpmux - allow options to be passed in via a file (issue #355)
+
+- 11/24/2017: version 0.6.1
+  This is a binary compatible release.
+  * lossless performance and compression improvements + a new 'cruncher' mode
+    (-m 6 -q 100)
+  * ARM performance improvements with clang (15-20% w/ndk r15c, issue #339)
+  * webp-js: emscripten/webassembly based javascript decoder
+  * miscellaneous bug & build fixes (issue #329, #332, #343, #353, #360, #361,
+    #363)
+  Tool updates / additions:
+    added webpinfo - prints file format information (issue #330)
+    gif2webp - loop behavior modified to match Chrome M63+ (crbug.com/649264);
+               '-loop_compatibility' can be used for the old behavior
+
+- 1/26/2017: version 0.6.0
+  * lossless performance and compression improvements
+  * miscellaneous performance improvements (SSE2, NEON, MSA)
+  * webpmux gained a -duration option allowing for frame timing modification
+  * new img2webp utility allowing a sequence of images to be converted to
+    animated webp
+  * API changes:
+    - libwebp:
+      WebPPictureSharpARGBToYUVA
+      WebPPlaneDistortion
+    - libwebpmux / gif2webp:
+      WebPAnimEncoderOptions: kmax <= 0 now disables keyframes, kmax == 1
+                              forces all keyframes. See mux.h and the gif2webp
+                              manpage for details.
+
+- 12/13/2016: version 0.5.2
+  This is a binary compatible release.
+  This release covers CVE-2016-8888 and CVE-2016-9085.
+  * further security related hardening in the tools; fixes to
+    gif2webp/AnimEncoder (issues #310, #314, #316, #322), cwebp/libwebp (issue
+    #312)
+  * full libwebp (encoder & decoder) iOS framework; libwebpdecoder
+    WebP.framework renamed to WebPDecoder.framework (issue #307)
+  * CMake support for Android Studio (2.2)
+  * miscellaneous build related fixes (issue #306, #313)
+  * miscellaneous documentation improvements (issue #225)
+  * minor lossy encoder fixes and improvements
+
+- 6/14/2016: version 0.5.1
+  This is a binary compatible release.
+  * miscellaneous bug fixes (issues #280, #289)
+  * reverted alpha plane encoding with color cache for compatibility with
+    libwebp 0.4.0->0.4.3 (issues #291, #298)
+  * lossless encoding performance improvements
+  * memory reduction in both lossless encoding and decoding
+  * force mux output to be in the extended format (VP8X) when undefined chunks
+    are present (issue #294)
+  * gradle, cmake build support
+  * workaround for compiler bug causing 64-bit decode failures on android
+    devices using clang-3.8 in the r11c NDK
+  * various WebPAnimEncoder improvements
+
+- 12/17/2015: version 0.5.0
+  * miscellaneous bug & build fixes (issues #234, #258, #274, #275, #278)
+  * encoder & decoder speed-ups on x86/ARM/MIPS for lossy & lossless
+    - note! YUV->RGB conversion was sped-up, but the results will be slightly
+      different from previous releases
+  * various lossless encoder improvements
+  * gif2webp improvements, -min_size option added
+  * tools fully support input from stdin and output to stdout (issue #168)
+  * New WebPAnimEncoder API for creating animations
+  * New WebPAnimDecoder API for decoding animations
+  * other API changes:
+    - libwebp:
+      WebPPictureSmartARGBToYUVA() (-pre 4 in cwebp)
+      WebPConfig::exact (-exact in cwebp; -alpha_cleanup is now the default)
+      WebPConfig::near_lossless (-near_lossless in cwebp)
+      WebPFree() (free'ing webp allocated memory in other languages)
+      WebPConfigLosslessPreset()
+      WebPMemoryWriterClear()
+    - libwebpdemux: removed experimental fragment related fields and functions
+    - libwebpmux: WebPMuxSetCanvasSize()
+  * new libwebpextras library with some uncommon import functions:
+    WebPImportGray/WebPImportRGB565/WebPImportRGB4444
+
+- 10/15/15: version 0.4.4
+  This is a binary compatible release.
+  * rescaling out-of-bounds read fix (issue #254)
+  * various build fixes and improvements (issues #253, #259, #262, #267, #268)
+  * container documentation update
+  * gif2webp transparency fix (issue #245)
+
+- 3/3/15: version 0.4.3
+  This is a binary compatible release.
+  * Android / gcc / iOS / MSVS build fixes and improvements
+  * lossless decode fix (issue #239 -- since 0.4.0)
+  * documentation / vwebp updates for animation
+  * multi-threading fix (issue #234)
+
+- 10/13/14: version 0.4.2
+  This is a binary compatible release.
+  * Android / gcc build fixes
+  * (Windows) fix reading from stdin and writing to stdout
+  * gif2webp: miscellaneous fixes
+  * fix 'alpha-leak' with lossy compression (issue #220)
+  * the lossless bitstream spec has been amended to reflect the current code
+
+- 7/24/14: version 0.4.1
+  This is a binary compatible release.
+  * AArch64 (arm64) & MIPS support/optimizations
+  * NEON assembly additions:
+    - ~25% faster lossy decode / encode (-m 4)
+    - ~10% faster lossless decode
+    - ~5-10% faster lossless encode (-m 3/4)
+  * dwebp/vwebp can read from stdin
+  * cwebp/gif2webp can write to stdout
+  * cwebp can read webp files; useful if storing sources as webp lossless
+
 - 12/19/13: version 0.4.0
   * improved gif2webp tool
   * numerous fixes, compression improvement and speed-up
@@ -63,7 +267,8 @@
 - 9/19/11: version 0.1.3
   * Advanced decoding APIs.
   * On-the-fly cropping and rescaling of images.
-  * SSE2 instructions for decoding performance optimizations on x86 based platforms.
+  * SSE2 instructions for decoding performance optimizations on x86 based
+    platforms.
   * Support Multi-threaded decoding.
   * 40% improvement in Decoding performance.
   * Add support for RGB565, RGBA4444 & ARGB image colorspace.

PATENTS

@@ -1,22 +1,23 @@
 Additional IP Rights Grant (Patents)
+------------------------------------
 
-"This implementation" means the copyrightable works distributed by
-Google as part of the WebM Project.
+"These implementations" means the copyrightable works that implement the WebM
+codecs distributed by Google as part of the WebM Project.
 
-Google hereby grants to you a perpetual, worldwide, non-exclusive,
-no-charge, royalty-free, irrevocable (except as stated in this section)
-patent license to make, have made, use, offer to sell, sell, import,
-transfer, and otherwise run, modify and propagate the contents of this
-implementation of VP8, where such license applies only to those patent
-claims, both currently owned by Google and acquired in the future,
-licensable by Google that are necessarily infringed by this
-implementation of VP8. This grant does not include claims that would be
-infringed only as a consequence of further modification of this
-implementation. If you or your agent or exclusive licensee institute or
-order or agree to the institution of patent litigation against any
-entity (including a cross-claim or counterclaim in a lawsuit) alleging
-that this implementation of VP8 or any code incorporated within this
-implementation of VP8 constitutes direct or contributory patent
-infringement, or inducement of patent infringement, then any patent
-rights granted to you under this License for this implementation of VP8
-shall terminate as of the date such litigation is filed.
+Google hereby grants to you a perpetual, worldwide, non-exclusive, no-charge,
+royalty-free, irrevocable (except as stated in this section) patent license to
+make, have made, use, offer to sell, sell, import, transfer, and otherwise
+run, modify and propagate the contents of these implementations of WebM, where
+such license applies only to those patent claims, both currently owned by
+Google and acquired in the future, licensable by Google that are necessarily
+infringed by these implementations of WebM. This grant does not include claims
+that would be infringed only as a consequence of further modification of these
+implementations. If you or your agent or exclusive licensee institute or order
+or agree to the institution of patent litigation or any other patent
+enforcement activity against any entity (including a cross-claim or
+counterclaim in a lawsuit) alleging that any of these implementations of WebM
+or any code incorporated within any of these implementations of WebM
+constitute direct or contributory patent infringement, or inducement of
+patent infringement, then any patent rights granted to you under this License
+for these implementations of WebM shall terminate as of the date such
+litigation is filed.

PRESUBMIT.py

@@ -0,0 +1,245 @@
+# Copyright (c) 2021, Google Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#   * Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#
+#   * Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+#
+#   * Neither the name of Google nor the names of its contributors may
+#     be used to endorse or promote products derived from this software
+#     without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+"""Top-level presubmit script for libwebp.
+
+See https://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts for
+details on the presubmit API built into depot_tools.
+"""
+
+import re
+import subprocess2
+
+USE_PYTHON3 = True
+_BASH_INDENTATION = "2"
+_GIT_COMMIT_SUBJECT_LENGTH = 65
+_INCLUDE_BASH_FILES_ONLY = [r".*\.sh$"]
+_INCLUDE_MAN_FILES_ONLY = [r"man/.+\.1$"]
+_INCLUDE_SOURCE_FILES_ONLY = [r".*\.[ch]$"]
+_LIBWEBP_MAX_LINE_LENGTH = 80
+
+
+def _CheckCommitSubjectLength(input_api, output_api):
+  """Ensures commit's subject length is no longer than 65 chars."""
+  name = "git-commit subject"
+  cmd = ["git", "log", "-1", "--pretty=%s"]
+  start = input_api.time.time()
+  proc = subprocess2.Popen(
+      cmd,
+      stderr=subprocess2.PIPE,
+      stdout=subprocess2.PIPE,
+      universal_newlines=True)
+
+  stdout, _ = proc.communicate()
+  duration = input_api.time.time() - start
+
+  if not re.match(r"^Revert",
+                  stdout) and (len(stdout) - 1) > _GIT_COMMIT_SUBJECT_LENGTH:
+    failure_msg = (
+        "The commit subject: %s is too long (%d chars)\n"
+        "Try to keep this to 50 or less (up to 65 is permitted for "
+        "non-reverts).\n"
+        "https://www.git-scm.com/book/en/v2/Distributed-Git-Contributing-to-a-"
+        "Project#_commit_guidelines") % (stdout, len(stdout) - 1)
+    return output_api.PresubmitError("%s\n (%4.2fs) failed\n%s" %
+                                     (name, duration, failure_msg))
+
+  return output_api.PresubmitResult("%s\n (%4.2fs) success" % (name, duration))
+
+
+def _CheckDuplicateFiles(input_api, output_api):
+  """Ensures there are not repeated filenames."""
+  all_files = []
+  for f in input_api.change.AllFiles():
+    for include_file in _INCLUDE_SOURCE_FILES_ONLY:
+      if re.match(include_file, f):
+        all_files.append(f)
+        break
+
+  basename_to_path = {}
+  for f in all_files:
+    basename_file = input_api.basename(f)
+    if basename_file in basename_to_path:
+      basename_to_path[basename_file].append(f)
+    else:
+      basename_to_path[basename_file] = [f]
+
+  dupes = []
+  for files in basename_to_path.values():
+    if len(files) > 1:
+      dupes.extend(files)
+
+  if dupes:
+    return output_api.PresubmitError(
+        "Duplicate source files, rebase or rename some to make them unique:\n%s"
+        % dupes)
+  return output_api.PresubmitResult("No duplicates, success\n")
+
+
+def _GetFilesToSkip(input_api):
+  return list(input_api.DEFAULT_FILES_TO_SKIP) + [
+      r"swig/.*\.py$",
+      r"\.pylintrc$",
+  ]
+
+
+def _RunManCmd(input_api, output_api, man_file):
+  """man command wrapper."""
+  cmd = ["man", "--warnings", "-EUTF-8", "-l", "-Tutf8", "-Z", man_file]
+  name = "Check %s file." % man_file
+  start = input_api.time.time()
+  output, _ = subprocess2.communicate(
+      cmd, stdout=None, stderr=subprocess2.PIPE, universal_newlines=True)
+  duration = input_api.time.time() - start
+  if output[1]:
+    return output_api.PresubmitError("%s\n%s (%4.2fs) failed\n%s" %
+                                     (name, " ".join(cmd), duration, output[1]))
+  return output_api.PresubmitResult("%s\n%s (%4.2fs)\n" %
+                                    (name, " ".join(cmd), duration))
+
+
+def _RunShellCheckCmd(input_api, output_api, bash_file):
+  """shellcheck command wrapper."""
+  cmd = ["shellcheck", "-x", "-oall", "-sbash", bash_file]
+  name = "Check %s file." % bash_file
+  start = input_api.time.time()
+  output, rc = subprocess2.communicate(
+      cmd, stdout=None, stderr=subprocess2.PIPE, universal_newlines=True)
+  duration = input_api.time.time() - start
+  if rc == 0:
+    return output_api.PresubmitResult("%s\n%s (%4.2fs)\n" %
+                                      (name, " ".join(cmd), duration))
+  return output_api.PresubmitError("%s\n%s (%4.2fs) failed\n%s" %
+                                   (name, " ".join(cmd), duration, output[1]))
+
+
+def _RunShfmtCheckCmd(input_api, output_api, bash_file):
+  """shfmt command wrapper."""
+  cmd = [
+      "shfmt", "-i", _BASH_INDENTATION, "-bn", "-ci", "-sr", "-kp", "-d",
+      bash_file
+  ]
+  name = "Check %s file." % bash_file
+  start = input_api.time.time()
+  output, rc = subprocess2.communicate(
+      cmd, stdout=None, stderr=subprocess2.PIPE, universal_newlines=True)
+  duration = input_api.time.time() - start
+  if rc == 0:
+    return output_api.PresubmitResult("%s\n%s (%4.2fs)\n" %
+                                      (name, " ".join(cmd), duration))
+  return output_api.PresubmitError("%s\n%s (%4.2fs) failed\n%s" %
+                                   (name, " ".join(cmd), duration, output[1]))
+
+
+def _RunCmdOnCheckedFiles(input_api, output_api, run_cmd, files_to_check):
+  """Ensure that libwebp/ files are clean."""
+  file_filter = lambda x: input_api.FilterSourceFile(
+      x, files_to_check=files_to_check, files_to_skip=None)
+
+  affected_files = input_api.change.AffectedFiles(file_filter=file_filter)
+  results = [
+      run_cmd(input_api, output_api, f.AbsoluteLocalPath())
+      for f in affected_files
+  ]
+  return results
+
+
+def _CommonChecks(input_api, output_api):
+  """Ensures this patch does not have trailing spaces, extra EOLs,
+     or long lines.
+  """
+  results = []
+  results.extend(
+      input_api.canned_checks.CheckChangeHasNoCrAndHasOnlyOneEol(
+          input_api, output_api))
+  results.extend(
+      input_api.canned_checks.CheckChangeHasNoTabs(input_api, output_api))
+  results.extend(
+      input_api.canned_checks.CheckChangeHasNoStrayWhitespace(
+          input_api, output_api))
+  results.append(_CheckCommitSubjectLength(input_api, output_api))
+  results.append(_CheckDuplicateFiles(input_api, output_api))
+
+  source_file_filter = lambda x: input_api.FilterSourceFile(
+      x, files_to_skip=_GetFilesToSkip(input_api))
+  results.extend(
+      input_api.canned_checks.CheckLongLines(
+          input_api,
+          output_api,
+          maxlen=_LIBWEBP_MAX_LINE_LENGTH,
+          source_file_filter=source_file_filter))
+
+  results.extend(
+      input_api.canned_checks.CheckPatchFormatted(
+          input_api,
+          output_api,
+          check_clang_format=False,
+          check_python=True,
+          result_factory=output_api.PresubmitError))
+  results.extend(
+      _RunCmdOnCheckedFiles(input_api, output_api, _RunManCmd,
+                            _INCLUDE_MAN_FILES_ONLY))
+  # Run pylint.
+  results.extend(
+      input_api.canned_checks.RunPylint(
+          input_api,
+          output_api,
+          files_to_skip=_GetFilesToSkip(input_api),
+          pylintrc=".pylintrc",
+          version="2.7"))
+
+  # Binaries shellcheck and shfmt are not installed in depot_tools.
+  # Installation is needed
+  try:
+    subprocess2.communicate(["shellcheck", "--version"])
+    results.extend(
+        _RunCmdOnCheckedFiles(input_api, output_api, _RunShellCheckCmd,
+                              _INCLUDE_BASH_FILES_ONLY))
+    print("shfmt")
+    subprocess2.communicate(["shfmt", "-version"])
+    results.extend(
+        _RunCmdOnCheckedFiles(input_api, output_api, _RunShfmtCheckCmd,
+                              _INCLUDE_BASH_FILES_ONLY))
+  except OSError as os_error:
+    results.append(
+        output_api.PresubmitPromptWarning(
+            "%s\nPlease install missing binaries locally." % os_error.args[0]))
+  return results
+
+
+def CheckChangeOnUpload(input_api, output_api):
+  results = []
+  results.extend(_CommonChecks(input_api, output_api))
+  return results
+
+
+def CheckChangeOnCommit(input_api, output_api):
+  results = []
+  results.extend(_CommonChecks(input_api, output_api))
+  return results

README

@@ -1,601 +0,0 @@
-          __   __  ____  ____  ____
-         /  \\/  \/  _ \/  _ )/  _ \
-         \       /   __/  _  \   __/
-          \__\__/\____/\_____/__/ ____  ___
-                / _/ /    \    \ /  _ \/ _/
-               /  \_/   / /   \ \   __/  \__
-               \____/____/\_____/_____/____/v0.4.0
-
-Description:
-============
-
-WebP codec: library to encode and decode images in WebP format. This package
-contains the library that can be used in other programs to add WebP support,
-as well as the command line tools 'cwebp' and 'dwebp'.
-
-See http://developers.google.com/speed/webp
-
-Latest sources are available from http://www.webmproject.org/code/
-
-It is released under the same license as the WebM project.
-See http://www.webmproject.org/license/software/ or the
-file "COPYING" file for details. An additional intellectual
-property rights grant can be found in the file PATENTS.
-
-Building:
-=========
-
-Windows build:
---------------
-
-By running:
-
-  nmake /f Makefile.vc CFG=release-static RTLIBCFG=static OBJDIR=output
-
-the directory output\release-static\(x64|x86)\bin will contain the tools
-cwebp.exe and dwebp.exe. The directory output\release-static\(x64|x86)\lib will
-contain the libwebp static library.
-The target architecture (x86/x64) is detected by Makefile.vc from the Visual
-Studio compiler (cl.exe) available in the system path.
-
-Unix build using makefile.unix:
--------------------------------
-
-On platforms with GNU tools installed (gcc and make), running
-
-  make -f makefile.unix
-
-will build the binaries examples/cwebp and examples/dwebp, along
-with the static library src/libwebp.a. No system-wide installation
-is supplied, as this is a simple alternative to the full installation
-system based on the autoconf tools (see below).
-Please refer to makefile.unix for additional details and customizations.
-
-Using autoconf tools:
----------------------
-When building from git sources, you will need to run autogen.sh to generate the
-configure script.
-
-./configure
-make
-make install
-
-should be all you need to have the following files
-
-/usr/local/include/webp/decode.h
-/usr/local/include/webp/encode.h
-/usr/local/include/webp/types.h
-/usr/local/lib/libwebp.*
-/usr/local/bin/cwebp
-/usr/local/bin/dwebp
-
-installed.
-
-Note: A decode-only library, libwebpdecoder, is available using the
-'--enable-libwebpdecoder' flag. The encode library is built separately and can
-be installed independently using a minor modification in the corresponding
-Makefile.am configure files (see comments there). See './configure --help' for
-more options.
-
-SWIG bindings:
---------------
-
-To generate language bindings from swig/libwebp.swig at least swig-1.3
-(http://www.swig.org) is required.
-
-Currently the following functions are mapped:
-Decode:
-  WebPGetDecoderVersion
-  WebPGetInfo
-  WebPDecodeRGBA
-  WebPDecodeARGB
-  WebPDecodeBGRA
-  WebPDecodeBGR
-  WebPDecodeRGB
-
-Encode:
-  WebPGetEncoderVersion
-  WebPEncodeRGBA
-  WebPEncodeBGRA
-  WebPEncodeRGB
-  WebPEncodeBGR
-  WebPEncodeLosslessRGBA
-  WebPEncodeLosslessBGRA
-  WebPEncodeLosslessRGB
-  WebPEncodeLosslessBGR
-
-See swig/README for more detailed build instructions.
-
-Java bindings:
-
-To build the swig-generated JNI wrapper code at least JDK-1.5 (or equivalent)
-is necessary for enum support. The output is intended to be a shared object /
-DLL that can be loaded via System.loadLibrary("webp_jni").
-
-Python bindings:
-
-To build the swig-generated Python extension code at least Python 2.6 is
-required. Python < 2.6 may build with some minor changes to libwebp.swig or the
-generated code, but is untested.
-
-Encoding tool:
-==============
-
-The examples/ directory contains tools for encoding (cwebp) and
-decoding (dwebp) images.
-
-The easiest use should look like:
-  cwebp input.png -q 80 -o output.webp
-which will convert the input file to a WebP file using a quality factor of 80
-on a 0->100 scale (0 being the lowest quality, 100 being the best. Default
-value is 75).
-You might want to try the -lossless flag too, which will compress the source
-(in RGBA format) without any loss. The -q quality parameter will in this case
-control the amount of processing time spent trying to make the output file as
-small as possible.
-
-A longer list of options is available using the -longhelp command line flag:
-
-> cwebp -longhelp
-Usage:
- cwebp [-preset <...>] [options] in_file [-o out_file]
-
-If input size (-s) for an image is not specified, it is assumed to be a PNG,
-JPEG or TIFF file.
-options:
-  -h / -help  ............ short help
-  -H / -longhelp  ........ long help
-  -q <float> ............. quality factor (0:small..100:big)
-  -alpha_q <int> ......... Transparency-compression quality (0..100).
-  -preset <string> ....... Preset setting, one of:
-                            default, photo, picture,
-                            drawing, icon, text
-     -preset must come first, as it overwrites other parameters.
-  -m <int> ............... compression method (0=fast, 6=slowest)
-  -segments <int> ........ number of segments to use (1..4)
-  -size <int> ............ Target size (in bytes)
-  -psnr <float> .......... Target PSNR (in dB. typically: 42)
-
-  -s <int> <int> ......... Input size (width x height) for YUV
-  -sns <int> ............. Spatial Noise Shaping (0:off, 100:max)
-  -f <int> ............... filter strength (0=off..100)
-  -sharpness <int> ....... filter sharpness (0:most .. 7:least sharp)
-  -strong ................ use strong filter instead of simple (default).
-  -nostrong .............. use simple filter instead of strong.
-  -partition_limit <int> . limit quality to fit the 512k limit on
-                           the first partition (0=no degradation ... 100=full)
-  -pass <int> ............ analysis pass number (1..10)
-  -crop <x> <y> <w> <h> .. crop picture with the given rectangle
-  -resize <w> <h> ........ resize picture (after any cropping)
-  -mt .................... use multi-threading if available
-  -low_memory ............ reduce memory usage (slower encoding)
-  -map <int> ............. print map of extra info.
-  -print_psnr ............ prints averaged PSNR distortion.
-  -print_ssim ............ prints averaged SSIM distortion.
-  -print_lsim ............ prints local-similarity distortion.
-  -d <file.pgm> .......... dump the compressed output (PGM file).
-  -alpha_method <int> .... Transparency-compression method (0..1)
-  -alpha_filter <string> . predictive filtering for alpha plane.
-                           One of: none, fast (default) or best.
-  -alpha_cleanup ......... Clean RGB values in transparent area.
-  -blend_alpha <hex> ..... Blend colors against background color
-                           expressed as RGB values written in
-                           hexadecimal, e.g. 0xc0e0d0 for red=0xc0
-                           green=0xe0 and blue=0xd0.
-  -noalpha ............... discard any transparency information.
-  -lossless .............. Encode image losslessly.
-  -hint <string> ......... Specify image characteristics hint.
-                           One of: photo, picture or graph
-
-  -metadata <string> ..... comma separated list of metadata to
-                           copy from the input to the output if present.
-                           Valid values: all, none (default), exif, icc, xmp
-
-  -short ................. condense printed message
-  -quiet ................. don't print anything.
-  -version ............... print version number and exit.
-  -noasm ................. disable all assembly optimizations.
-  -v ..................... verbose, e.g. print encoding/decoding times
-  -progress .............. report encoding progress
-
-Experimental Options:
-  -jpeg_like ............. Roughly match expected JPEG size.
-  -af .................... auto-adjust filter strength.
-  -pre <int> ............. pre-processing filter
-
-
-The main options you might want to try in order to further tune the
-visual quality are:
- -preset
- -sns
- -f
- -m
-
-Namely:
-  * 'preset' will set up a default encoding configuration targeting a
-     particular type of input. It should appear first in the list of options,
-     so that subsequent options can take effect on top of this preset.
-     Default value is 'default'.
-  * 'sns' will progressively turn on (when going from 0 to 100) some additional
-     visual optimizations (like: segmentation map re-enforcement). This option
-     will balance the bit allocation differently. It tries to take bits from the
-     "easy" parts of the picture and use them in the "difficult" ones instead.
-     Usually, raising the sns value (at fixed -q value) leads to larger files,
-     but with better quality.
-     Typical value is around '75'.
-  * 'f' option directly links to the filtering strength used by the codec's
-     in-loop processing. The higher the value, the smoother the
-     highly-compressed area will look. This is particularly useful when aiming
-     at very small files. Typical values are around 20-30. Note that using the
-     option -strong/-nostrong will change the type of filtering. Use "-f 0" to
-     turn filtering off.
-  * 'm' controls the trade-off between encoding speed and quality. Default is 4.
-     You can try -m 5 or -m 6 to explore more (time-consuming) encoding
-     possibilities. A lower value will result in faster encoding at the expense
-     of quality.
-
-Decoding tool:
-==============
-
-There is a decoding sample in examples/dwebp.c which will take
-a .webp file and decode it to a PNG image file (amongst other formats).
-This is simply to demonstrate the use of the API. You can verify the
-file test.webp decodes to exactly the same as test_ref.ppm by using:
-
- cd examples
- ./dwebp test.webp -ppm -o test.ppm
- diff test.ppm test_ref.ppm
-
-The full list of options is available using -h:
-
-> dwebp -h
-Usage: dwebp in_file [options] [-o out_file]
-
-Decodes the WebP image file to PNG format [Default]
-Use following options to convert into alternate image formats:
-  -pam ......... save the raw RGBA samples as a color PAM
-  -ppm ......... save the raw RGB samples as a color PPM
-  -bmp ......... save as uncompressed BMP format
-  -tiff ........ save as uncompressed TIFF format
-  -pgm ......... save the raw YUV samples as a grayscale PGM
-                 file with IMC4 layout
-  -yuv ......... save the raw YUV samples in flat layout
-
- Other options are:
-  -version  .... print version number and exit.
-  -nofancy ..... don't use the fancy YUV420 upscaler.
-  -nofilter .... disable in-loop filtering.
-  -nodither .... disable dithering.
-  -dither <d> .. dithering strength (in 0..100)
-  -mt .......... use multi-threading
-  -crop <x> <y> <w> <h> ... crop output with the given rectangle
-  -scale <w> <h> .......... scale the output (*after* any cropping)
-  -alpha ....... only save the alpha plane.
-  -incremental . use incremental decoding (useful for tests)
-  -h     ....... this help message.
-  -v     ....... verbose (e.g. print encoding/decoding times)
-  -noasm ....... disable all assembly optimizations.
-
-Visualization tool:
-===================
-
-There's a little self-serve visualization tool called 'vwebp' under the
-examples/ directory. It uses OpenGL to open a simple drawing window and show
-a decoded WebP file. It's not yet integrated in the automake build system, but
-you can try to manually compile it using the recommendations below.
-
-Usage: vwebp in_file [options]
-
-Decodes the WebP image file and visualize it using OpenGL
-Options are:
-  -version  .... print version number and exit.
-  -noicc ....... don't use the icc profile if present.
-  -nofancy ..... don't use the fancy YUV420 upscaler.
-  -nofilter .... disable in-loop filtering.
-  -dither <int>  dithering strength (0..100). Default=50.
-  -mt .......... use multi-threading.
-  -info ........ print info.
-  -h     ....... this help message.
-
-Keyboard shortcuts:
-  'c' ................ toggle use of color profile.
-  'i' ................ overlay file information.
-  'q' / 'Q' / ESC .... quit.
-
-Building:
----------
-
-Prerequisites:
-1) OpenGL & OpenGL Utility Toolkit (GLUT)
-  Linux:
-    $ sudo apt-get install freeglut3-dev mesa-common-dev
-  Mac + XCode:
-    - These libraries should be available in the OpenGL / GLUT frameworks.
-  Windows:
-    http://freeglut.sourceforge.net/index.php#download
-
-2) (Optional) qcms (Quick Color Management System)
-  i. Download qcms from Mozilla / Chromium:
-    http://hg.mozilla.org/mozilla-central/file/0e7639e3bdfb/gfx/qcms
-    http://src.chromium.org/viewvc/chrome/trunk/src/third_party/qcms
-  ii. Build and archive the source files as libqcms.a / qcms.lib
-  iii. Update makefile.unix / Makefile.vc
-    a) Define WEBP_HAVE_QCMS
-    b) Update include / library paths to reference the qcms directory.
-
-Build using makefile.unix / Makefile.vc:
-$ make -f makefile.unix examples/vwebp
-> nmake /f Makefile.vc CFG=release-static \
-    ../obj/x64/release-static/bin/vwebp.exe
-
-Animated GIF conversion:
-========================
-Animated GIF files can be converted to WebP files with animation using the
-gif2webp utility available under examples/. The files can then be viewed using
-vwebp.
-
-Usage:
- gif2webp [options] gif_file -o webp_file
-options:
-  -h / -help  ............ this help
-  -lossy ................. Encode image using lossy compression.
-  -mixed ................. For each frame in the image, pick lossy
-                           or lossless compression heuristically.
-  -q <float> ............. quality factor (0:small..100:big)
-  -m <int> ............... compression method (0=fast, 6=slowest)
-  -kmin <int> ............ Min distance between key frames
-  -kmax <int> ............ Max distance between key frames
-  -f <int> ............... filter strength (0=off..100)
-  -metadata <string> ..... comma separated list of metadata to
-                           copy from the input to the output if present.
-                           Valid values: all, none, icc, xmp (default)
-  -mt .................... use multi-threading if available
-
-  -version ............... print version number and exit.
-  -v ..................... verbose.
-  -quiet ................. don't print anything.
-
-Building:
----------
-With the libgif development files installed, gif2webp can be built using
-makefile.unix:
-$ make -f makefile.unix examples/gif2webp
-
-or using autoconf:
-$ ./configure --enable-everything
-$ make
-
-Encoding API:
-=============
-
-The main encoding functions are available in the header src/webp/encode.h
-The ready-to-use ones are:
-size_t WebPEncodeRGB(const uint8_t* rgb, int width, int height, int stride,
-                     float quality_factor, uint8_t** output);
-size_t WebPEncodeBGR(const uint8_t* bgr, int width, int height, int stride,
-                     float quality_factor, uint8_t** output);
-size_t WebPEncodeRGBA(const uint8_t* rgba, int width, int height, int stride,
-                      float quality_factor, uint8_t** output);
-size_t WebPEncodeBGRA(const uint8_t* bgra, int width, int height, int stride,
-                      float quality_factor, uint8_t** output);
-
-They will convert raw RGB samples to a WebP data. The only control supplied
-is the quality factor.
-
-There are some variants for using the lossless format:
-
-size_t WebPEncodeLosslessRGB(const uint8_t* rgb, int width, int height,
-                             int stride, uint8_t** output);
-size_t WebPEncodeLosslessBGR(const uint8_t* bgr, int width, int height,
-                             int stride, uint8_t** output);
-size_t WebPEncodeLosslessRGBA(const uint8_t* rgba, int width, int height,
-                              int stride, uint8_t** output);
-size_t WebPEncodeLosslessBGRA(const uint8_t* bgra, int width, int height,
-                              int stride, uint8_t** output);
-
-Of course in this case, no quality factor is needed since the compression
-occurs without loss of the input values, at the expense of larger output sizes.
-
-Advanced encoding API:
-----------------------
-
-A more advanced API is based on the WebPConfig and WebPPicture structures.
-
-WebPConfig contains the encoding settings and is not tied to a particular
-picture.
-WebPPicture contains input data, on which some WebPConfig will be used for
-compression.
-The encoding flow looks like:
-
--------------------------------------- BEGIN PSEUDO EXAMPLE
-
-#include <webp/encode.h>
-
-  // Setup a config, starting form a preset and tuning some additional
-  // parameters
-  WebPConfig config;
-  if (!WebPConfigPreset(&config, WEBP_PRESET_PHOTO, quality_factor))
-    return 0;   // version error
-  }
-  // ... additional tuning
-  config.sns_strength = 90;
-  config.filter_sharpness = 6;
-  config_error = WebPValidateConfig(&config);  // not mandatory, but useful
-
-  // Setup the input data
-  WebPPicture pic;
-  if (!WebPPictureInit(&pic)) {
-    return 0;  // version error
-  }
-  pic.width = width;
-  pic.height = height;
-  // allocated picture of dimension width x height
-  if (!WebPPictureAllocate(&pic)) {
-    return 0;   // memory error
-  }
-  // at this point, 'pic' has been initialized as a container,
-  // and can receive the Y/U/V samples.
-  // Alternatively, one could use ready-made import functions like
-  // WebPPictureImportRGB(), which will take care of memory allocation.
-  // In any case, past this point, one will have to call
-  // WebPPictureFree(&pic) to reclaim memory.
-
-  // Set up a byte-output write method. WebPMemoryWriter, for instance.
-  WebPMemoryWriter wrt;
-  pic.writer = MyFileWriter;
-  pic.custom_ptr = my_opaque_structure_to_make_MyFileWriter_work;
-  // initialize 'wrt' here...
-
-  // Compress!
-  int ok = WebPEncode(&config, &pic);   // ok = 0 => error occurred!
-  WebPPictureFree(&pic);  // must be called independently of the 'ok' result.
-
-  // output data should have been handled by the writer at that point.
-
--------------------------------------- END PSEUDO EXAMPLE
-
-Decoding API:
-=============
-
-This is mainly just one function to call:
-
-#include "webp/decode.h"
-uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size,
-                       int* width, int* height);
-
-Please have a look at the file src/webp/decode.h for the details.
-There are variants for decoding in BGR/RGBA/ARGB/BGRA order, along with
-decoding to raw Y'CbCr samples. One can also decode the image directly into a
-pre-allocated buffer.
-
-To detect a WebP file and gather the picture's dimensions, the function:
-  int WebPGetInfo(const uint8_t* data, size_t data_size,
-                  int* width, int* height);
-is supplied. No decoding is involved when using it.
-
-Incremental decoding API:
-=========================
-
-In the case when data is being progressively transmitted, pictures can still
-be incrementally decoded using a slightly more complicated API. Decoder state
-is stored into an instance of the WebPIDecoder object. This object can be
-created with the purpose of decoding either RGB or Y'CbCr samples.
-For instance:
-
-  WebPDecBuffer buffer;
-  WebPInitDecBuffer(&buffer);
-  buffer.colorspace = MODE_BGR;
-  ...
-  WebPIDecoder* idec = WebPINewDecoder(&buffer);
-
-As data is made progressively available, this incremental-decoder object
-can be used to decode the picture further. There are two (mutually exclusive)
-ways to pass freshly arrived data:
-
-either by appending the fresh bytes:
-
-  WebPIAppend(idec, fresh_data, size_of_fresh_data);
-
-or by just mentioning the new size of the transmitted data:
-
-  WebPIUpdate(idec, buffer, size_of_transmitted_buffer);
-
-Note that 'buffer' can be modified between each call to WebPIUpdate, in
-particular when the buffer is resized to accommodate larger data.
-
-These functions will return the decoding status: either VP8_STATUS_SUSPENDED if
-decoding is not finished yet or VP8_STATUS_OK when decoding is done. Any other
-status is an error condition.
-
-The 'idec' object must always be released (even upon an error condition) by
-calling: WebPDelete(idec).
-
-To retrieve partially decoded picture samples, one must use the corresponding
-method: WebPIDecGetRGB or WebPIDecGetYUVA.
-It will return the last displayable pixel row.
-
-Lastly, note that decoding can also be performed into a pre-allocated pixel
-buffer. This buffer must be passed when creating a WebPIDecoder, calling
-WebPINewRGB() or WebPINewYUVA().
-
-Please have a look at the src/webp/decode.h header for further details.
-
-Advanced Decoding API:
-======================
-
-WebP decoding supports an advanced API which provides on-the-fly cropping and
-rescaling, something of great usefulness on memory-constrained environments like
-mobile phones. Basically, the memory usage will scale with the output's size,
-not the input's, when one only needs a quick preview or a zoomed in portion of
-an otherwise too-large picture. Some CPU can be saved too, incidentally.
-
--------------------------------------- BEGIN PSEUDO EXAMPLE
-     // A) Init a configuration object
-     WebPDecoderConfig config;
-     CHECK(WebPInitDecoderConfig(&config));
-
-     // B) optional: retrieve the bitstream's features.
-     CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK);
-
-     // C) Adjust 'config' options, if needed
-     config.options.no_fancy_upsampling = 1;
-     config.options.use_scaling = 1;
-     config.options.scaled_width = scaledWidth();
-     config.options.scaled_height = scaledHeight();
-     // etc.
-
-     // D) Specify 'config' output options for specifying output colorspace.
-     // Optionally the external image decode buffer can also be specified.
-     config.output.colorspace = MODE_BGRA;
-     // Optionally, the config.output can be pointed to an external buffer as
-     // well for decoding the image. This externally supplied memory buffer
-     // should be big enough to store the decoded picture.
-     config.output.u.RGBA.rgba = (uint8_t*) memory_buffer;
-     config.output.u.RGBA.stride = scanline_stride;
-     config.output.u.RGBA.size = total_size_of_the_memory_buffer;
-     config.output.is_external_memory = 1;
-
-     // E) Decode the WebP image. There are two variants w.r.t decoding image.
-     // The first one (E.1) decodes the full image and the second one (E.2) is
-     // used to incrementally decode the image using small input buffers.
-     // Any one of these steps can be used to decode the WebP image.
-
-     // E.1) Decode full image.
-     CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK);
-
-     // E.2) Decode image incrementally.
-     WebPIDecoder* const idec = WebPIDecode(NULL, NULL, &config);
-     CHECK(idec != NULL);
-     while (bytes_remaining > 0) {
-       VP8StatusCode status = WebPIAppend(idec, input, bytes_read);
-       if (status == VP8_STATUS_OK || status == VP8_STATUS_SUSPENDED) {
-         bytes_remaining -= bytes_read;
-       } else {
-         break;
-       }
-     }
-     WebPIDelete(idec);
-
-     // F) Decoded image is now in config.output (and config.output.u.RGBA).
-     // It can be saved, displayed or otherwise processed.
-
-     // G) Reclaim memory allocated in config's object. It's safe to call
-     // this function even if the memory is external and wasn't allocated
-     // by WebPDecode().
-     WebPFreeDecBuffer(&config.output);
-
--------------------------------------- END PSEUDO EXAMPLE
-
-Bugs:
-=====
-
-Please report all bugs to our issue tracker:
-    http://code.google.com/p/webp/issues
-Patches welcome! See this page to get started:
-    http://www.webmproject.org/code/contribute/submitting-patches/
-
-Discuss:
-========
-
-Email: webp-discuss@webmproject.org
-Web: http://groups.google.com/a/webmproject.org/group/webp-discuss

README.md

@@ -0,0 +1,53 @@
+# WebP Codec
+
+```
+      __   __  ____  ____  ____
+     /  \\/  \/  _ \/  _ )/  _ \
+     \       /   __/  _  \   __/
+      \__\__/\____/\_____/__/ ____  ___
+            / _/ /    \    \ /  _ \/ _/
+           /  \_/   / /   \ \   __/  \__
+           \____/____/\_____/_____/____/v1.2.3
+```
+
+WebP codec is a library to encode and decode images in WebP format. This package
+contains the library that can be used in other programs to add WebP support, as
+well as the command line tools 'cwebp' and 'dwebp' to compress and decompress
+images respectively.
+
+See https://developers.google.com/speed/webp for details on the image format.
+
+The latest source tree is available at
+https://chromium.googlesource.com/webm/libwebp
+
+It is released under the same license as the WebM project. See
+https://www.webmproject.org/license/software/ or the "COPYING" file for details.
+An additional intellectual property rights grant can be found in the file
+PATENTS.
+
+## Building
+
+See the [building documentation](doc/building.md).
+
+## Encoding and Decoding Tools
+
+The examples/ directory contains tools to encode and decode images and
+animations, view information about WebP images, and more. See the
+[tools documentation](doc/tools.md).
+
+## APIs
+
+See the [APIs documentation](doc/api.md), and API usage examples in the
+`examples/` directory.
+
+## Bugs
+
+Please report all bugs to the issue tracker: https://bugs.chromium.org/p/webp
+
+Patches welcome! See [how to contribute](CONTRIBUTING.md).
+
+## Discuss
+
+Email: webp-discuss@webmproject.org
+
+Web: https://groups.google.com/a/webmproject.org/group/webp-discuss

README.mux

@@ -1,186 +0,0 @@
-          __   __  ____  ____  ____  __ __  _     __ __
-         /  \\/  \/  _ \/  _ \/  _ \/  \  \/ \___/_ / _\
-         \       /   __/  _  \   __/      /  /  (_/  /__
-          \__\__/\_____/_____/__/  \__//_/\_____/__/___/v0.2.0
-
-
-Description:
-============
-
-WebPMux: set of two libraries 'Mux' and 'Demux' for creation, extraction and
-manipulation of an extended format WebP file, which can have features like
-color profile, metadata and animation. Reference command-line tools 'webpmux'
-and 'vwebp' as well as the WebP container specification
-'doc/webp-container-spec.txt' are also provided in this package.
-
-WebP Mux tool:
-==============
-
-The examples/ directory contains a tool (webpmux) for manipulating WebP
-files. The webpmux tool can be used to create an extended format WebP file and
-also to extract or strip relevant data from such a file.
-
-A list of options is available using the -help command line flag:
-
-> webpmux -help
-Usage: webpmux -get GET_OPTIONS INPUT -o OUTPUT
-       webpmux -set SET_OPTIONS INPUT -o OUTPUT
-       webpmux -strip STRIP_OPTIONS INPUT -o OUTPUT
-       webpmux -frame FRAME_OPTIONS [-frame...] [-loop LOOP_COUNT]
-               [-bgcolor BACKGROUND_COLOR] -o OUTPUT
-       webpmux -info INPUT
-       webpmux [-h|-help]
-       webpmux -version
-
-GET_OPTIONS:
- Extract relevant data.
-   icc       Get ICC profile.
-   exif      Get EXIF metadata.
-   xmp       Get XMP metadata.
-   frame n   Get nth frame.
-
-SET_OPTIONS:
- Set color profile/metadata.
-   icc  file.icc     Set ICC profile.
-   exif file.exif    Set EXIF metadata.
-   xmp  file.xmp     Set XMP metadata.
-   where:    'file.icc' contains the ICC profile to be set,
-             'file.exif' contains the EXIF metadata to be set
-             'file.xmp' contains the XMP metadata to be set
-
-STRIP_OPTIONS:
- Strip color profile/metadata.
-   icc       Strip ICC profile.
-   exif      Strip EXIF metadata.
-   xmp       Strip XMP metadata.
-
-FRAME_OPTIONS(i):
- Create animation.
-   file_i +di+[xi+yi[+mi[bi]]]
-   where:    'file_i' is the i'th animation frame (WebP format),
-             'di' is the pause duration before next frame.
-             'xi','yi' specify the image offset for this frame.
-             'mi' is the dispose method for this frame (0 or 1).
-             'bi' is the blending method for this frame (+b or -b).
-
-LOOP_COUNT:
- Number of times to repeat the animation.
- Valid range is 0 to 65535 [Default: 0 (infinite)].
-
-BACKGROUND_COLOR:
- Background color of the canvas.
-  A,R,G,B
-  where:    'A', 'R', 'G' and 'B' are integers in the range 0 to 255 specifying
-            the Alpha, Red, Green and Blue component values respectively
-            [Default: 255,255,255,255].
-
-INPUT & OUTPUT are in WebP format.
-
-Note: The nature of EXIF, XMP and ICC data is not checked and is assumed to be
-valid.
-
-Visualization tool:
-===================
-
-The examples/ directory also contains a tool (vwebp) for viewing WebP files.
-It decodes the image and visualizes it using OpenGL. See the libwebp README
-for details on building and running this program.
-
-Mux API:
-========
-The Mux API contains methods for adding data to and reading data from WebP
-files. This API currently supports XMP/EXIF metadata, ICC profile and animation.
-Other features may be added in subsequent releases.
-
-Example#1 (pseudo code): Creating a WebPMux object with image data, color
-profile and XMP metadata.
-
-  int copy_data = 0;
-  WebPMux* mux = WebPMuxNew();
-  // ... (Prepare image data).
-  WebPMuxSetImage(mux, &image, copy_data);
-  // ... (Prepare ICC profile data).
-  WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
-  // ... (Prepare XMP metadata).
-  WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
-  // Get data from mux in WebP RIFF format.
-  WebPMuxAssemble(mux, &output_data);
-  WebPMuxDelete(mux);
-  // ... (Consume output_data; e.g. write output_data.bytes to file).
-  WebPDataClear(&output_data);
-
-
-Example#2 (pseudo code): Get image and color profile data from a WebP file.
-
-  int copy_data = 0;
-  // ... (Read data from file).
-  WebPMux* mux = WebPMuxCreate(&data, copy_data);
-  WebPMuxGetFrame(mux, 1, &image);
-  // ... (Consume image; e.g. call WebPDecode() to decode the data).
-  WebPMuxGetChunk(mux, "ICCP", &icc_profile);
-  // ... (Consume icc_profile).
-  WebPMuxDelete(mux);
-  free(data);
-
-
-For a detailed Mux API reference, please refer to the header file
-(src/webp/mux.h).
-
-Demux API:
-==========
-The Demux API enables extraction of images and extended format data from
-WebP files. This API currently supports reading of XMP/EXIF metadata, ICC
-profile and animated images. Other features may be added in subsequent
-releases.
-
-Code Example: Demuxing WebP data to extract all the frames, ICC profile
-and EXIF/XMP metadata.
-
-  WebPDemuxer* demux = WebPDemux(&webp_data);
-  uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
-  uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
-  // ... (Get information about the features present in the WebP file).
-  uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
-
-  // ... (Iterate over all frames).
-  WebPIterator iter;
-  if (WebPDemuxGetFrame(demux, 1, &iter)) {
-    do {
-      // ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
-      // ... and get other frame properties like width, height, offsets etc.
-      // ... see 'struct WebPIterator' below for more info).
-    } while (WebPDemuxNextFrame(&iter));
-    WebPDemuxReleaseIterator(&iter);
-  }
-
-  // ... (Extract metadata).
-  WebPChunkIterator chunk_iter;
-  if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
-  // ... (Consume the ICC profile in 'chunk_iter.chunk').
-  WebPDemuxReleaseChunkIterator(&chunk_iter);
-  if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
-  // ... (Consume the EXIF metadata in 'chunk_iter.chunk').
-  WebPDemuxReleaseChunkIterator(&chunk_iter);
-  if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
-  // ... (Consume the XMP metadata in 'chunk_iter.chunk').
-  WebPDemuxReleaseChunkIterator(&chunk_iter);
-  WebPDemuxDelete(demux);
-
-
-For a detailed Demux API reference, please refer to the header file
-(src/webp/demux.h).
-
-
-Bugs:
-=====
-
-Please report all bugs to our issue tracker:
-    http://code.google.com/p/webp/issues
-Patches welcome! See this page to get started:
-    http://www.webmproject.org/code/contribute/submitting-patches/
-
-Discuss:
-========
-
-Email: webp-discuss@webmproject.org
-Web: http://groups.google.com/a/webmproject.org/group/webp-discuss

build.gradle

@@ -0,0 +1,442 @@
+// Define dependencies.
+buildscript {
+  repositories {
+    maven {
+      url "https://jcenter.bintray.com"
+    }
+  }
+  dependencies {
+    classpath "com.android.tools.build:gradle:${ANDROID_GRADLE_PLUGIN_VERSION}"
+  }
+}
+
+// Define versions in the project.
+project.ext {
+  buildToolsVersion = "${BUILD_TOOLS_VERSION}"
+  compileSdkVersion = COMPILE_SDK_VERSION.toInteger()
+}
+
+// Core libraries and executables.
+apply plugin: "c"
+def NEON
+model {
+  buildTypes {
+    debug
+    release
+  }
+  platforms {
+    arm {
+      architecture "arm"
+    }
+    arm64 {
+      architecture "arm64"
+    }
+    x86 {
+      architecture "x86"
+    }
+    x64 {
+      architecture "x86_64"
+    }
+    mips32r2
+    mips32r5
+    mips64r6
+  }
+  toolChains {
+    gcc(Gcc) {
+      target("mips32r2") {
+        cCompiler.args "-mips32r2"
+      }
+      target("mips32r5") {
+        cCompiler.args "-mips32r5"
+      }
+      target("mips64r6") {
+        cCompiler.args "-mips64r6"
+      }
+    }
+  }
+  binaries {
+    all {
+      if (toolChain in Gcc) {
+        cCompiler.args "-fPIC"
+        cCompiler.args "-Wall"
+        cCompiler.define "ANDROID"
+        cCompiler.define "HAVE_MALLOC_H"
+      }
+      // Optimizations.
+      if (buildType == buildTypes.release) {
+        if (toolChain in Gcc) {
+          cCompiler.args "-finline-functions"
+          cCompiler.args "-ffast-math"
+          cCompiler.args "-ffunction-sections"
+          cCompiler.args "-fdata-sections"
+        }
+        if (toolChain in Clang) {
+          cCompiler.args "-frename-registers -s"
+        }
+      }
+      // mips32 fails to build with clang from r14b
+      // https://bugs.chromium.org/p/webp/issues/detail?id=343
+      if (toolChain in Clang) {
+        if (getTargetPlatform() == "mips") {
+          cCompiler.args "-no-integrated-as"
+        }
+      }
+      // Check for NEON usage.
+      if (getTargetPlatform() == "arm") {
+        NEON = "c.neon"
+        cCompiler.define "HAVE_CPU_FEATURES_H"
+      } else {
+        NEON = "c"
+      }
+
+      cCompiler.args "-I" + file(".").absolutePath
+    }
+    // Link to pthread for shared libraries.
+    withType(SharedLibraryBinarySpec) {
+      if (toolChain in Gcc) {
+        cCompiler.define "HAVE_PTHREAD"
+        cCompiler.define "WEBP_USE_THREAD"
+        linker.args "-pthread"
+      }
+    }
+  }
+  components {
+    webp(NativeLibrarySpec) {
+      sources {
+        c {
+          source {
+            srcDir "sharpyuv"
+            include "sharpyuv.c"
+            include "sharpyuv_csp.c"
+            include "sharpyuv_dsp.c"
+            include "sharpyuv_gamma.c"
+            include "sharpyuv_neon.c"
+            include "sharpyuv_sse2.c"
+            srcDir "src/dec"
+            include "alpha_dec.c"
+            include "buffer_dec.c"
+            include "frame_dec.c"
+            include "idec_dec.c"
+            include "io_dec.c"
+            include "quant_dec.c"
+            include "tree_dec.c"
+            include "vp8_dec.c"
+            include "vp8l_dec.c"
+            include "webp_dec.c"
+            srcDir "src/dsp"
+            include "alpha_processing.c"
+            include "alpha_processing_mips_dsp_r2.c"
+            include "alpha_processing_neon.$NEON"
+            include "alpha_processing_sse2.c"
+            include "alpha_processing_sse41.c"
+            include "cpu.c"
+            include "dec.c"
+            include "dec_clip_tables.c"
+            include "dec_mips32.c"
+            include "dec_mips_dsp_r2.c"
+            include "dec_msa.c"
+            include "dec_neon.$NEON"
+            include "dec_sse2.c"
+            include "dec_sse41.c"
+            include "filters.c"
+            include "filters_mips_dsp_r2.c"
+            include "filters_msa.c"
+            include "filters_neon.$NEON"
+            include "filters_sse2.c"
+            include "lossless.c"
+            include "lossless_mips_dsp_r2.c"
+            include "lossless_msa.c"
+            include "lossless_neon.$NEON"
+            include "lossless_sse2.c"
+            include "lossless_sse41.c"
+            include "rescaler.c"
+            include "rescaler_mips32.c"
+            include "rescaler_mips_dsp_r2.c"
+            include "rescaler_msa.c"
+            include "rescaler_neon.$NEON"
+            include "rescaler_sse2.c"
+            include "upsampling.c"
+            include "upsampling_mips_dsp_r2.c"
+            include "upsampling_msa.c"
+            include "upsampling_neon.$NEON"
+            include "upsampling_sse2.c"
+            include "upsampling_sse41.c"
+            include "yuv.c"
+            include "yuv_mips32.c"
+            include "yuv_mips_dsp_r2.c"
+            include "yuv_neon.$NEON"
+            include "yuv_sse2.c"
+            include "yuv_sse41.c"
+            srcDir "src/utils"
+            include "bit_reader_utils.c"
+            include "color_cache_utils.c"
+            include "filters_utils.c"
+            include "huffman_utils.c"
+            include "quant_levels_dec_utils.c"
+            include "random_utils.c"
+            include "rescaler_utils.c"
+            include "thread_utils.c"
+            include "utils.c"
+            srcDir "src/dsp"
+            include "cost.c"
+            include "cost_mips32.c"
+            include "cost_mips_dsp_r2.c"
+            include "cost_neon.$NEON"
+            include "cost_sse2.c"
+            include "enc.c"
+            include "enc_mips32.c"
+            include "enc_mips_dsp_r2.c"
+            include "enc_msa.c"
+            include "enc_neon.$NEON"
+            include "enc_sse2.c"
+            include "enc_sse41.c"
+            include "lossless_enc.c"
+            include "lossless_enc_mips32.c"
+            include "lossless_enc_mips_dsp_r2.c"
+            include "lossless_enc_msa.c"
+            include "lossless_enc_neon.$NEON"
+            include "lossless_enc_sse2.c"
+            include "lossless_enc_sse41.c"
+            include "ssim.c"
+            include "ssim_sse2.c"
+            srcDir "src/enc"
+            include "alpha_enc.c"
+            include "analysis_enc.c"
+            include "backward_references_cost_enc.c"
+            include "backward_references_enc.c"
+            include "config_enc.c"
+            include "cost_enc.c"
+            include "filter_enc.c"
+            include "frame_enc.c"
+            include "histogram_enc.c"
+            include "iterator_enc.c"
+            include "near_lossless_enc.c"
+            include "picture_enc.c"
+            include "picture_csp_enc.c"
+            include "picture_psnr_enc.c"
+            include "picture_rescale_enc.c"
+            include "picture_tools_enc.c"
+            include "predictor_enc.c"
+            include "quant_enc.c"
+            include "syntax_enc.c"
+            include "token_enc.c"
+            include "tree_enc.c"
+            include "vp8l_enc.c"
+            include "webp_enc.c"
+            srcDir "src/utils"
+            include "bit_writer_utils.c"
+            include "huffman_encode_utils.c"
+            include "quant_levels_utils.c"
+          }
+          exportedHeaders {
+            srcDir "src"
+          }
+        }
+      }
+    }
+
+    webpdemux(NativeLibrarySpec) {
+      sources {
+        c {
+          source {
+            srcDir "src/demux"
+            include "anim_decode.c"
+            include "demux.c"
+          }
+        }
+      }
+    }
+
+    webpmux(NativeLibrarySpec) {
+      sources {
+        c {
+          source {
+            srcDir "src/mux/"
+            include "anim_encode.c"
+            include "muxedit.c"
+            include "muxinternal.c"
+            include "muxread.c"
+          }
+        }
+      }
+    }
+
+    // Executables from examples.
+    example_util(NativeLibrarySpec) {
+      binaries {
+        all {
+          lib library: "webp", linkage: "static"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./examples"
+            include "example_util.c"
+          }
+        }
+      }
+    }
+
+    imageio_util(NativeLibrarySpec) {
+      binaries {
+        all {
+          lib library: "webp", linkage: "static"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./imageio"
+            include "imageio_util.c"
+          }
+        }
+      }
+    }
+
+    imagedec(NativeLibrarySpec) {
+      binaries {
+        all {
+          lib library: "webpdemux", linkage: "static"
+          lib library: "webp", linkage: "static"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./imageio"
+            include "image_dec.c"
+            include "jpegdec.c"
+            include "metadata.c"
+            include "pngdec.c"
+            include "pnmdec.c"
+            include "tiffdec.c"
+            include "webpdec.c"
+          }
+        }
+      }
+    }
+
+    imageenc(NativeLibrarySpec) {
+      binaries {
+        all {
+          lib library: "webp", linkage: "static"
+          lib library: "imageio_util", linkage: "static"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./imageio"
+            include "image_enc.c"
+          }
+        }
+      }
+    }
+
+    cwebp(NativeExecutableSpec) {
+      binaries {
+        all {
+          lib library: "example_util", linkage: "static"
+          lib library: "imagedec", linkage: "static"
+          lib library: "imageio_util", linkage: "static"
+          lib library: "webpdemux", linkage: "static"
+          lib library: "webp", linkage: "static"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./examples"
+            include "cwebp.c"
+          }
+        }
+      }
+    }
+
+    dwebp(NativeExecutableSpec) {
+      binaries {
+        all {
+          lib library: "example_util", linkage: "static"
+          lib library: "imagedec", linkage: "static"
+          lib library: "imageenc", linkage: "static"
+          lib library: "imageio_util", linkage: "static"
+          lib library: "webpdemux", linkage: "static"
+          lib library: "webp"
+        }
+      }
+      sources {
+        c {
+          source {
+              srcDir "./examples"
+              include "dwebp.c"
+          }
+        }
+      }
+    }
+
+    webpmux_example(NativeExecutableSpec) {
+      binaries {
+        all {
+          lib library: "example_util", linkage: "static"
+          lib library: "imageio_util", linkage: "static"
+          lib library: "webpmux", linkage: "static"
+          lib library: "webp"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./examples"
+            include "webpmux.c"
+          }
+        }
+      }
+    }
+
+    img2webp_example(NativeExecutableSpec) {
+      binaries {
+        all {
+          lib library: "example_util", linkage: "static"
+          lib library: "imagedec", linkage: "static"
+          lib library: "imageio_util", linkage: "static"
+          lib library: "webpmux", linkage: "static"
+          lib library: "webpdemux", linkage: "static"
+          lib library: "webp"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./examples"
+            include "img2webp.c"
+          }
+        }
+      }
+    }
+
+    webpinfo_example(NativeExecutableSpec) {
+      binaries {
+        all {
+          lib library: "example_util", linkage: "static"
+          lib library: "imageio_util", linkage: "static"
+          lib library: "webp"
+        }
+      }
+      sources {
+        c {
+          source {
+            srcDir "./examples"
+            include "webpinfo.c"
+          }
+        }
+      }
+    }
+  }
+  tasks {
+    // Task to test all possible configurations.
+    buildAllExecutables(Task) {
+      dependsOn $.binaries.findAll { it.buildable }
+    }
+  }
+}

cmake/WebPConfig.cmake.in

@@ -0,0 +1,11 @@
+set(WebP_VERSION @PROJECT_VERSION@)
+set(WEBP_VERSION ${WebP_VERSION})
+
+@PACKAGE_INIT@
+
+include ("${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")
+
+set(WebP_INCLUDE_DIRS "@CMAKE_INSTALL_FULL_INCLUDEDIR@")
+set(WEBP_INCLUDE_DIRS ${WebP_INCLUDE_DIRS})
+set(WebP_LIBRARIES "@INSTALLED_LIBRARIES@")
+set(WEBP_LIBRARIES "${WebP_LIBRARIES}")

cmake/config.h.in

@@ -0,0 +1,149 @@
+/* Adapted from the autotools src/webp/config.h.in.  */
+
+/* Define if building universal (internal helper macro) */
+/* TODO: handle properly in CMake */
+#cmakedefine AC_APPLE_UNIVERSAL_BUILD 1
+
+/* Set to 1 if __builtin_bswap16 is available */
+#cmakedefine HAVE_BUILTIN_BSWAP16 1
+
+/* Set to 1 if __builtin_bswap32 is available */
+#cmakedefine HAVE_BUILTIN_BSWAP32 1
+
+/* Set to 1 if __builtin_bswap64 is available */
+#cmakedefine HAVE_BUILTIN_BSWAP64 1
+
+/* Define to 1 if you have the <cpu-features.h> header file. */
+#cmakedefine HAVE_CPU_FEATURES_H 1
+
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#cmakedefine HAVE_DLFCN_H 1
+
+/* Define to 1 if you have the <GLUT/glut.h> header file. */
+#cmakedefine HAVE_GLUT_GLUT_H 1
+
+/* Define to 1 if you have the <GL/glut.h> header file. */
+#cmakedefine HAVE_GL_GLUT_H 1
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#cmakedefine HAVE_INTTYPES_H 1
+
+/* Define to 1 if you have the <memory.h> header file. */
+#cmakedefine HAVE_MEMORY_H 1
+
+/* Define to 1 if you have the <OpenGL/glut.h> header file. */
+#cmakedefine HAVE_OPENGL_GLUT_H 1
+
+/* Have PTHREAD_PRIO_INHERIT. */
+#cmakedefine HAVE_PTHREAD_PRIO_INHERIT @HAVE_PTHREAD_PRIO_INHERIT@
+
+/* Define to 1 if you have the <shlwapi.h> header file. */
+#cmakedefine HAVE_SHLWAPI_H 1
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#cmakedefine HAVE_STDINT_H 1
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#cmakedefine HAVE_STDLIB_H 1
+
+/* Define to 1 if you have the <strings.h> header file. */
+#cmakedefine HAVE_STRINGS_H 1
+
+/* Define to 1 if you have the <string.h> header file. */
+#cmakedefine HAVE_STRING_H 1
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#cmakedefine HAVE_SYS_STAT_H 1
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#cmakedefine HAVE_SYS_TYPES_H 1
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#cmakedefine HAVE_UNISTD_H 1
+
+/* Define to 1 if you have the <wincodec.h> header file. */
+#cmakedefine HAVE_WINCODEC_H 1
+
+/* Define to 1 if you have the <windows.h> header file. */
+#cmakedefine HAVE_WINDOWS_H 1
+
+/* Define to the sub-directory in which libtool stores uninstalled libraries.
+   */
+/* TODO: handle properly in CMake */
+#cmakedefine LT_OBJDIR "@LT_OBJDIR@"
+
+/* Name of package */
+#cmakedefine PACKAGE "@PROJECT_NAME@"
+
+/* Define to the address where bug reports for this package should be sent. */
+#cmakedefine PACKAGE_BUGREPORT "@PACKAGE_BUGREPORT@"
+
+/* Define to the full name of this package. */
+#cmakedefine PACKAGE_NAME "@PACKAGE_NAME@"
+
+/* Define to the full name and version of this package. */
+#cmakedefine PACKAGE_STRING "@PACKAGE_STRING@"
+
+/* Define to the one symbol short name of this package. */
+#cmakedefine PACKAGE_TARNAME "@PACKAGE_TARNAME@"
+
+/* Define to the home page for this package. */
+#cmakedefine PACKAGE_URL "@PACKAGE_URL@"
+
+/* Define to the version of this package. */
+#cmakedefine PACKAGE_VERSION "@PACKAGE_VERSION@"
+
+/* Define to 1 if you have the ANSI C header files. */
+#cmakedefine STDC_HEADERS 1
+
+/* Version number of package */
+#cmakedefine VERSION "@VERSION@"
+
+/* Set to 1 if GIF library is installed */
+#cmakedefine WEBP_HAVE_GIF 1
+
+/* Set to 1 if OpenGL is supported */
+#cmakedefine WEBP_HAVE_GL 1
+
+/* Set to 1 if JPEG library is installed */
+#cmakedefine WEBP_HAVE_JPEG 1
+
+/* Set to 1 if NEON is supported */
+#cmakedefine WEBP_HAVE_NEON
+
+/* Set to 1 if runtime detection of NEON is enabled */
+/* TODO: handle properly in CMake */
+#cmakedefine WEBP_HAVE_NEON_RTCD
+
+/* Set to 1 if PNG library is installed */
+#cmakedefine WEBP_HAVE_PNG 1
+
+/* Set to 1 if SDL library is installed */
+#cmakedefine WEBP_HAVE_SDL 1
+
+/* Set to 1 if SSE2 is supported */
+#cmakedefine WEBP_HAVE_SSE2 1
+
+/* Set to 1 if SSE4.1 is supported */
+#cmakedefine WEBP_HAVE_SSE41 1
+
+/* Set to 1 if TIFF library is installed */
+#cmakedefine WEBP_HAVE_TIFF 1
+
+/* Enable near lossless encoding */
+#cmakedefine WEBP_NEAR_LOSSLESS 1
+
+/* Undefine this to disable thread support. */
+#cmakedefine WEBP_USE_THREAD 1
+
+/* Define WORDS_BIGENDIAN to 1 if your processor stores words with the most
+   significant byte first (like Motorola and SPARC, unlike Intel). */
+#if defined AC_APPLE_UNIVERSAL_BUILD
+# if defined __BIG_ENDIAN__
+#  define WORDS_BIGENDIAN 1
+# endif
+#else
+# ifndef WORDS_BIGENDIAN
+#  undef WORDS_BIGENDIAN
+# endif
+#endif

cmake/cpu.cmake

@@ -0,0 +1,162 @@
+#  Copyright (c) 2021 Google LLC.
+#
+#  Use of this source code is governed by a BSD-style license
+#  that can be found in the LICENSE file in the root of the source
+#  tree. An additional intellectual property rights grant can be found
+#  in the file PATENTS.  All contributing project authors may
+#  be found in the AUTHORS file in the root of the source tree.
+
+# Check for SIMD extensions.
+include(CMakePushCheckState)
+
+function(webp_check_compiler_flag WEBP_SIMD_FLAG ENABLE_SIMD)
+  if(NOT ENABLE_SIMD)
+    message(STATUS "Disabling ${WEBP_SIMD_FLAG} optimization.")
+    set(WEBP_HAVE_${WEBP_SIMD_FLAG} 0 PARENT_SCOPE)
+    return()
+  endif()
+  unset(WEBP_HAVE_FLAG_${WEBP_SIMD_FLAG} CACHE)
+  cmake_push_check_state()
+  set(CMAKE_REQUIRED_INCLUDES ${CMAKE_CURRENT_SOURCE_DIR})
+  check_c_source_compiles("
+      #include \"${CMAKE_CURRENT_LIST_DIR}/../src/dsp/dsp.h\"
+      int main(void) {
+        #if !defined(WEBP_USE_${WEBP_SIMD_FLAG})
+        this is not valid code
+        #endif
+        return 0;
+      }
+    " WEBP_HAVE_FLAG_${WEBP_SIMD_FLAG})
+  cmake_pop_check_state()
+  if(WEBP_HAVE_FLAG_${WEBP_SIMD_FLAG})
+    set(WEBP_HAVE_${WEBP_SIMD_FLAG} 1 PARENT_SCOPE)
+  else()
+    set(WEBP_HAVE_${WEBP_SIMD_FLAG} 0 PARENT_SCOPE)
+  endif()
+endfunction()
+
+# those are included in the names of WEBP_USE_* in c++ code.
+set(WEBP_SIMD_FLAGS "SSE41;SSE2;MIPS32;MIPS_DSP_R2;NEON;MSA")
+set(WEBP_SIMD_FILE_EXTENSIONS
+    "_sse41.c;_sse2.c;_mips32.c;_mips_dsp_r2.c;_neon.c;_msa.c")
+if(MSVC AND CMAKE_C_COMPILER_ID STREQUAL "MSVC")
+  # With at least Visual Studio 12 (2013)+ /arch is not necessary to build SSE2
+  # or SSE4 code unless a lesser /arch is forced. MSVC does not have a SSE4
+  # flag, but an AVX one. Using that with SSE4 code risks generating illegal
+  # instructions when used on machines with SSE4 only. The flags are left for
+  # older (untested) versions to avoid any potential compatibility issues.
+  if(MSVC_VERSION GREATER_EQUAL 1800 AND NOT CMAKE_C_FLAGS MATCHES "/arch:")
+    set(SIMD_ENABLE_FLAGS)
+  else()
+    set(SIMD_ENABLE_FLAGS "/arch:AVX;/arch:SSE2;;;;")
+  endif()
+  set(SIMD_DISABLE_FLAGS)
+else()
+  set(SIMD_ENABLE_FLAGS
+      "-msse4.1;-msse2;-mips32;-mdspr2;-mfpu=neon;-mmsa")
+  set(SIMD_DISABLE_FLAGS
+      "-mno-sse4.1;-mno-sse2;;-mno-dspr2;;-mno-msa")
+endif()
+
+set(WEBP_SIMD_FILES_TO_NOT_INCLUDE)
+set(WEBP_SIMD_FILES_TO_INCLUDE)
+set(WEBP_SIMD_FLAGS_TO_INCLUDE)
+
+if(${ANDROID})
+  if(${ANDROID_ABI} STREQUAL "armeabi-v7a")
+    # This is because Android studio uses the configuration "-march=armv7-a
+    # -mfloat-abi=softfp -mfpu=vfpv3-d16" that does not trigger neon
+    # optimizations but should (as this configuration does not exist anymore).
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpu=neon ")
+  endif()
+endif()
+
+list(LENGTH WEBP_SIMD_FLAGS WEBP_SIMD_FLAGS_LENGTH)
+math(EXPR WEBP_SIMD_FLAGS_RANGE "${WEBP_SIMD_FLAGS_LENGTH} - 1")
+
+foreach(I_SIMD RANGE ${WEBP_SIMD_FLAGS_RANGE})
+  # With Emscripten 2.0.9 -msimd128 -mfpu=neon will enable NEON, but the
+  # source will fail to compile.
+  if(EMSCRIPTEN AND ${I_SIMD} GREATER_EQUAL 2)
+    break()
+  endif()
+
+  list(GET WEBP_SIMD_FLAGS ${I_SIMD} WEBP_SIMD_FLAG)
+
+  # First try with no extra flag added as the compiler might have default flags
+  # (especially on Android).
+  unset(WEBP_HAVE_${WEBP_SIMD_FLAG} CACHE)
+  cmake_push_check_state()
+  set(CMAKE_REQUIRED_FLAGS)
+  webp_check_compiler_flag(${WEBP_SIMD_FLAG} ${WEBP_ENABLE_SIMD})
+  if(NOT WEBP_HAVE_${WEBP_SIMD_FLAG})
+    list(GET SIMD_ENABLE_FLAGS ${I_SIMD} SIMD_COMPILE_FLAG)
+    if(EMSCRIPTEN)
+      set(SIMD_COMPILE_FLAG "-msimd128 ${SIMD_COMPILE_FLAG}")
+    endif()
+    set(CMAKE_REQUIRED_FLAGS ${SIMD_COMPILE_FLAG})
+    webp_check_compiler_flag(${WEBP_SIMD_FLAG} ${WEBP_ENABLE_SIMD})
+  else()
+    if(MSVC AND SIMD_ENABLE_FLAGS)
+      # The detection for SSE2/SSE4 support under MSVC is based on the compiler
+      # version so e.g., clang-cl will require flags to enable the assembly.
+      list(GET SIMD_ENABLE_FLAGS ${I_SIMD} SIMD_COMPILE_FLAG)
+    else()
+      set(SIMD_COMPILE_FLAG " ")
+    endif()
+  endif()
+  # Check which files we should include or not.
+  list(GET WEBP_SIMD_FILE_EXTENSIONS ${I_SIMD} WEBP_SIMD_FILE_EXTENSION)
+  file(GLOB SIMD_FILES "${CMAKE_CURRENT_LIST_DIR}/../"
+            "src/dsp/*${WEBP_SIMD_FILE_EXTENSION}")
+  if(WEBP_HAVE_${WEBP_SIMD_FLAG})
+    # Memorize the file and flags.
+    foreach(FILE ${SIMD_FILES})
+      list(APPEND WEBP_SIMD_FILES_TO_INCLUDE ${FILE})
+      list(APPEND WEBP_SIMD_FLAGS_TO_INCLUDE ${SIMD_COMPILE_FLAG})
+    endforeach()
+  else()
+    # Remove the file from the list.
+    foreach(FILE ${SIMD_FILES})
+      list(APPEND WEBP_SIMD_FILES_NOT_TO_INCLUDE ${FILE})
+    endforeach()
+    # Explicitly disable SIMD.
+    if(SIMD_DISABLE_FLAGS)
+      list(GET SIMD_DISABLE_FLAGS ${I_SIMD} SIMD_COMPILE_FLAG)
+      include(CheckCCompilerFlag)
+      if(SIMD_COMPILE_FLAG)
+        # Between 3.17.0 and 3.18.2 check_cxx_compiler_flag() sets a normal
+        # variable at parent scope while check_cxx_source_compiles() continues
+        # to set an internal cache variable, so we unset both to avoid the
+        # failure / success state persisting between checks. See
+        # https://gitlab.kitware.com/cmake/cmake/-/issues/21207.
+        unset(HAS_COMPILE_FLAG)
+        unset(HAS_COMPILE_FLAG CACHE)
+        check_c_compiler_flag(${SIMD_COMPILE_FLAG} HAS_COMPILE_FLAG)
+        if(HAS_COMPILE_FLAG)
+          # Do one more check for Clang to circumvent CMake issue 13194.
+          if(COMMAND check_compiler_flag_common_patterns)
+            # Only in CMake 3.0 and above.
+            check_compiler_flag_common_patterns(COMMON_PATTERNS)
+          else()
+            set(COMMON_PATTERNS)
+          endif()
+          set(CMAKE_REQUIRED_DEFINITIONS ${SIMD_COMPILE_FLAG})
+          check_c_source_compiles("int main(void) {return 0;}"
+                                  FLAG_${SIMD_COMPILE_FLAG}
+                                  FAIL_REGEX
+                                  "warning: argument unused during compilation:"
+                                  ${COMMON_PATTERNS})
+          if(NOT FLAG_${SIMD_COMPILE_FLAG})
+            unset(HAS_COMPILE_FLAG)
+            unset(HAS_COMPILE_FLAG CACHE)
+          endif()
+        endif()
+        if(HAS_COMPILE_FLAG)
+          set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${SIMD_COMPILE_FLAG}")
+        endif()
+      endif()
+    endif()
+  endif()
+  cmake_pop_check_state()
+endforeach()

cmake/deps.cmake

@@ -0,0 +1,185 @@
+#  Copyright (c) 2021 Google LLC.
+#
+#  Use of this source code is governed by a BSD-style license
+#  that can be found in the LICENSE file in the root of the source
+#  tree. An additional intellectual property rights grant can be found
+#  in the file PATENTS.  All contributing project authors may
+#  be found in the AUTHORS file in the root of the source tree.
+
+# Generate the config.h to compile with specific intrinsics / libs.
+
+# Check for compiler options.
+include(CheckCSourceCompiles)
+check_c_source_compiles("
+    int main(void) {
+      (void)__builtin_bswap16(0);
+      return 0;
+    }
+  " HAVE_BUILTIN_BSWAP16)
+check_c_source_compiles("
+    int main(void) {
+      (void)__builtin_bswap32(0);
+      return 0;
+    }
+  " HAVE_BUILTIN_BSWAP32)
+check_c_source_compiles("
+    int main(void) {
+      (void)__builtin_bswap64(0);
+      return 0;
+    }
+  " HAVE_BUILTIN_BSWAP64)
+
+# Check for libraries.
+if(WEBP_USE_THREAD)
+  find_package(Threads)
+  if(Threads_FOUND)
+    # work around cmake bug on QNX (https://cmake.org/Bug/view.php?id=11333)
+    if(CMAKE_USE_PTHREADS_INIT AND NOT CMAKE_SYSTEM_NAME STREQUAL "QNX")
+      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pthread")
+    endif()
+    check_c_source_compiles("
+        #include <pthread.h>
+        int main (void) {
+          int attr = PTHREAD_PRIO_INHERIT;
+          return attr;
+        }
+      " FLAG_HAVE_PTHREAD_PRIO_INHERIT)
+    set(HAVE_PTHREAD_PRIO_INHERIT ${FLAG_HAVE_PTHREAD_PRIO_INHERIT})
+    list(APPEND WEBP_DEP_LIBRARIES Threads::Threads)
+  endif()
+  set(WEBP_USE_THREAD ${Threads_FOUND})
+endif()
+
+# TODO: this seems unused, check with autotools.
+set(LT_OBJDIR ".libs/")
+
+# Only useful for vwebp, so useless for now.
+find_package(OpenGL)
+set(WEBP_HAVE_GL ${OPENGL_FOUND})
+
+# Check if we need to link to the C math library. We do not look for it as it is
+# not found when cross-compiling, while it is here.
+check_c_source_compiles("
+    #include <math.h>
+    int main(int argc, char** argv) {
+      return (int)pow(argc, 2.5);
+    }
+  " HAVE_MATH_LIBRARY)
+if(NOT HAVE_MATH_LIBRARY)
+  message(STATUS "Adding -lm flag.")
+  list(APPEND WEBP_DEP_LIBRARIES m)
+endif()
+
+# Find the standard image libraries.
+set(WEBP_DEP_IMG_LIBRARIES)
+set(WEBP_DEP_IMG_INCLUDE_DIRS)
+foreach(I_LIB PNG JPEG TIFF)
+  # Disable tiff when compiling in static mode as it is failing on Ubuntu.
+  if(WEBP_LINK_STATIC AND ${I_LIB} STREQUAL "TIFF")
+    message("TIFF is disabled when statically linking.")
+    continue()
+  endif()
+  find_package(${I_LIB})
+  set(WEBP_HAVE_${I_LIB} ${${I_LIB}_FOUND})
+  if(${I_LIB}_FOUND)
+    list(APPEND WEBP_DEP_IMG_LIBRARIES ${${I_LIB}_LIBRARIES})
+    list(APPEND WEBP_DEP_IMG_INCLUDE_DIRS ${${I_LIB}_INCLUDE_DIR}
+                ${${I_LIB}_INCLUDE_DIRS})
+  endif()
+endforeach()
+if(WEBP_DEP_IMG_INCLUDE_DIRS)
+  list(REMOVE_DUPLICATES WEBP_DEP_IMG_INCLUDE_DIRS)
+endif()
+
+# GIF detection, gifdec isn't part of the imageio lib.
+include(CMakePushCheckState)
+set(WEBP_DEP_GIF_LIBRARIES)
+set(WEBP_DEP_GIF_INCLUDE_DIRS)
+find_package(GIF)
+set(WEBP_HAVE_GIF ${GIF_FOUND})
+if(GIF_FOUND)
+  # GIF find_package only locates the header and library, it doesn't fail
+  # compile tests when detecting the version, but falls back to 3 (as of at
+  # least cmake 3.7.2). Make sure the library links to avoid incorrect detection
+  # when cross compiling.
+  cmake_push_check_state()
+  set(CMAKE_REQUIRED_LIBRARIES ${GIF_LIBRARIES})
+  set(CMAKE_REQUIRED_INCLUDES ${GIF_INCLUDE_DIR})
+  check_c_source_compiles("
+      #include <gif_lib.h>
+      int main(void) {
+        (void)DGifOpenFileHandle;
+        return 0;
+      }
+      " GIF_COMPILES)
+  cmake_pop_check_state()
+  if(GIF_COMPILES)
+    list(APPEND WEBP_DEP_GIF_LIBRARIES ${GIF_LIBRARIES})
+    list(APPEND WEBP_DEP_GIF_INCLUDE_DIRS ${GIF_INCLUDE_DIR})
+  else()
+    unset(GIF_FOUND)
+  endif()
+endif()
+
+# Check for specific headers.
+include(CheckIncludeFiles)
+check_include_files("stdlib.h;stdarg.h;string.h;float.h" STDC_HEADERS)
+check_include_files(dlfcn.h HAVE_DLFCN_H)
+check_include_files(GLUT/glut.h HAVE_GLUT_GLUT_H)
+check_include_files(GL/glut.h HAVE_GL_GLUT_H)
+check_include_files(inttypes.h HAVE_INTTYPES_H)
+check_include_files(memory.h HAVE_MEMORY_H)
+check_include_files(OpenGL/glut.h HAVE_OPENGL_GLUT_H)
+check_include_files(shlwapi.h HAVE_SHLWAPI_H)
+check_include_files(stdint.h HAVE_STDINT_H)
+check_include_files(stdlib.h HAVE_STDLIB_H)
+check_include_files(strings.h HAVE_STRINGS_H)
+check_include_files(string.h HAVE_STRING_H)
+check_include_files(sys/stat.h HAVE_SYS_STAT_H)
+check_include_files(sys/types.h HAVE_SYS_TYPES_H)
+check_include_files(unistd.h HAVE_UNISTD_H)
+check_include_files(wincodec.h HAVE_WINCODEC_H)
+check_include_files(windows.h HAVE_WINDOWS_H)
+
+# Windows specifics
+if(HAVE_WINCODEC_H)
+  list(APPEND WEBP_DEP_LIBRARIES
+              shlwapi
+              ole32
+              windowscodecs)
+endif()
+
+# Check for SIMD extensions.
+include(${CMAKE_CURRENT_LIST_DIR}/cpu.cmake)
+
+# Define extra info.
+set(PACKAGE ${PROJECT_NAME})
+set(PACKAGE_NAME ${PROJECT_NAME})
+
+# Read from configure.ac.
+file(READ ${CMAKE_CURRENT_SOURCE_DIR}/configure.ac CONFIGURE_AC)
+string(REGEX MATCHALL
+             "\\[([0-9a-z\\.:/]*)\\]"
+             CONFIGURE_AC_PACKAGE_INFO
+             ${CONFIGURE_AC})
+function(strip_bracket VAR)
+  string(LENGTH ${${VAR}} TMP_LEN)
+  math(EXPR TMP_LEN ${TMP_LEN}-2)
+  string(SUBSTRING ${${VAR}}
+                   1
+                   ${TMP_LEN}
+                   TMP_SUB)
+  set(${VAR} ${TMP_SUB} PARENT_SCOPE)
+endfunction()
+
+list(GET CONFIGURE_AC_PACKAGE_INFO 1 PACKAGE_VERSION)
+strip_bracket(PACKAGE_VERSION)
+list(GET CONFIGURE_AC_PACKAGE_INFO 2 PACKAGE_BUGREPORT)
+strip_bracket(PACKAGE_BUGREPORT)
+list(GET CONFIGURE_AC_PACKAGE_INFO 3 PACKAGE_URL)
+strip_bracket(PACKAGE_URL)
+
+# Build more info.
+set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
+set(PACKAGE_TARNAME ${PACKAGE_NAME})
+set(VERSION ${PACKAGE_VERSION})

codereview.settings

@@ -0,0 +1,4 @@
+# This file is used by git cl to get repository specific information.
+GERRIT_HOST: True
+CODE_REVIEW_SERVER: chromium-review.googlesource.com
+GERRIT_SQUASH_UPLOADS: False

configure.ac

@@ -1,19 +1,25 @@
-AC_INIT([libwebp], [0.4.0],
-        [http://code.google.com/p/webp/issues],,
-        [http://developers.google.com/speed/webp])
-AC_CANONICAL_TARGET
+AC_INIT([libwebp], [1.2.3],
+        [https://bugs.chromium.org/p/webp],,
+        [https://developers.google.com/speed/webp])
+AC_CANONICAL_HOST
+AC_PREREQ([2.60])
 AM_INIT_AUTOMAKE([-Wall foreign subdir-objects])
 
 dnl === automake >= 1.12 requires this for 'unusual archivers' support.
 dnl === it must occur before LT_INIT (AC_PROG_LIBTOOL).
 m4_ifdef([AM_PROG_AR], [AM_PROG_AR])
 
-AC_PROG_LIBTOOL
+dnl === AC_PROG_LIBTOOL is deprecated.
+m4_ifdef([LT_INIT], [LT_INIT], [AC_PROG_LIBTOOL])
+AC_PROG_SED
 AM_PROG_CC_C_O
 
 dnl === Enable less verbose output when building.
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 
+dnl == test endianness
+AC_C_BIGENDIAN
+
 dnl === SET_IF_UNSET(shell_var, value)
 dnl ===   Set the shell variable 'shell_var' to 'value' if it is unset.
 AC_DEFUN([SET_IF_UNSET], [test "${$1+set}" = "set" || $1=$2])
@@ -22,42 +28,245 @@ AC_ARG_ENABLE([everything],
               AS_HELP_STRING([--enable-everything],
                              [Enable all optional targets. These can still be
                               disabled with --disable-target]),
-              [SET_IF_UNSET([enable_libwebpdecoder], [$enableval])
+              [SET_IF_UNSET([enable_libsharpyuv], [$enableval])
+               SET_IF_UNSET([enable_libwebpdecoder], [$enableval])
                SET_IF_UNSET([enable_libwebpdemux], [$enableval])
+               SET_IF_UNSET([enable_libwebpextras], [$enableval])
                SET_IF_UNSET([enable_libwebpmux], [$enableval])])
 
+dnl === Check whether libwebpmux should be built
+AC_MSG_CHECKING(whether libwebpmux is to be built)
+AC_ARG_ENABLE([libwebpmux],
+              AS_HELP_STRING([--disable-libwebpmux],
+                             [Disable libwebpmux @<:@default=no@:>@]),
+              [], [enable_libwebpmux=yes])
+AC_MSG_RESULT(${enable_libwebpmux-no})
+AM_CONDITIONAL([BUILD_MUX], [test "$enable_libwebpmux" = "yes"])
+
+dnl === Check whether libwebpdemux should be built
+AC_MSG_CHECKING(whether libwebpdemux is to be built)
+AC_ARG_ENABLE([libwebpdemux],
+              AS_HELP_STRING([--disable-libwebpdemux],
+                             [Disable libwebpdemux @<:@default=no@:>@]),
+              [], [enable_libwebpdemux=yes])
+AC_MSG_RESULT(${enable_libwebpdemux-no})
+AM_CONDITIONAL([BUILD_DEMUX], [test "$enable_libwebpdemux" = "yes"])
+
+dnl === Check whether decoder library should be built.
+AC_MSG_CHECKING(whether decoder library is to be built)
+AC_ARG_ENABLE([libwebpdecoder],
+              AS_HELP_STRING([--enable-libwebpdecoder],
+                             [Build libwebpdecoder @<:@default=no@:>@]))
+AC_MSG_RESULT(${enable_libwebpdecoder-no})
+AM_CONDITIONAL([BUILD_LIBWEBPDECODER], [test "$enable_libwebpdecoder" = "yes"])
+
+dnl === Check whether libwebpextras should be built
+AC_MSG_CHECKING(whether libwebpextras is to be built)
+AC_ARG_ENABLE([libwebpextras],
+              AS_HELP_STRING([--enable-libwebpextras],
+                             [Build libwebpextras @<:@default=no@:>@]))
+AC_MSG_RESULT(${enable_libwebpextras-no})
+AM_CONDITIONAL([BUILD_EXTRAS], [test "$enable_libwebpextras" = "yes"])
+
+dnl === If --enable-asserts is not defined, define NDEBUG
+
+AC_MSG_CHECKING(whether asserts are enabled)
+AC_ARG_ENABLE([asserts],
+              AS_HELP_STRING([--enable-asserts],
+                             [Enable assert checks]))
+if test "x${enable_asserts-no}" = "xno"; then
+  AM_CPPFLAGS="${AM_CPPFLAGS} -DNDEBUG"
+fi
+AC_MSG_RESULT(${enable_asserts-no})
+AC_SUBST([AM_CPPFLAGS])
+
 AC_ARG_WITH([pkgconfigdir], AS_HELP_STRING([--with-pkgconfigdir=DIR],
             [Path to the pkgconfig directory @<:@LIBDIR/pkgconfig@:>@]),
             [pkgconfigdir="$withval"], [pkgconfigdir='${libdir}/pkgconfig'])
 AC_SUBST([pkgconfigdir])
 
-dnl === TEST_AND_ADD_CFLAGS(flag)
-dnl ===   Checks whether $CC supports 'flag' and adds it to AM_CFLAGS on success.
+dnl === TEST_AND_ADD_CFLAGS(var, flag)
+dnl ===   Checks whether $CC supports 'flag' and adds it to 'var'
+dnl ===   on success.
 AC_DEFUN([TEST_AND_ADD_CFLAGS],
          [SAVED_CFLAGS="$CFLAGS"
-          CFLAGS="-Werror $1"
-          AC_MSG_CHECKING([whether $CC supports $1])
+          CFLAGS="-Werror $2"
+          AC_MSG_CHECKING([whether $CC supports $2])
           dnl Note AC_LANG_PROGRAM([]) uses an old-style main definition.
           AC_COMPILE_IFELSE([AC_LANG_SOURCE([int main(void) { return 0; }])],
                             [AC_MSG_RESULT([yes])]
                             dnl Simply append the variable avoiding a
                             dnl compatibility ifdef for AS_VAR_APPEND as this
                             dnl variable shouldn't grow all that large.
-                            [AM_CFLAGS="$AM_CFLAGS $1"],
+                            [$1="${$1} $2"],
                             [AC_MSG_RESULT([no])])
           CFLAGS="$SAVED_CFLAGS"])
-TEST_AND_ADD_CFLAGS([-Wall])
-TEST_AND_ADD_CFLAGS([-Wdeclaration-after-statement])
-TEST_AND_ADD_CFLAGS([-Wextra])
-TEST_AND_ADD_CFLAGS([-Wmissing-declarations])
-TEST_AND_ADD_CFLAGS([-Wmissing-prototypes])
-TEST_AND_ADD_CFLAGS([-Wold-style-definition])
-TEST_AND_ADD_CFLAGS([-Wshadow])
-TEST_AND_ADD_CFLAGS([-Wunused-but-set-variable])
-TEST_AND_ADD_CFLAGS([-Wunused])
-TEST_AND_ADD_CFLAGS([-Wvla])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-fvisibility=hidden])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wall])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wconstant-conversion])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wdeclaration-after-statement])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wextra])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wfloat-conversion])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wformat -Wformat-nonliteral])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wformat -Wformat-security])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wmissing-declarations])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wmissing-prototypes])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wold-style-definition])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wparentheses-equality])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wshadow])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wshorten-64-to-32])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wundef])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wunreachable-code-aggressive])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wunreachable-code])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wunused-but-set-variable])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wunused])
+TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wvla])
+# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62040
+# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61622
+AS_IF([test "$GCC" = "yes" ], [
+       gcc_version=`$CC -dumpversion`
+       gcc_wht_bug=""
+       case "$host_cpu" in
+         aarch64|arm64)
+          case "$gcc_version" in
+            4.9|4.9.0|4.9.1) gcc_wht_bug=yes ;;
+          esac
+       esac
+       AS_IF([test "$gcc_wht_bug" = "yes"], [
+              TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-frename-registers])])])
+# Use -flax-vector-conversions, if available, when building intrinsics with
+# older versions of gcc. The flag appeared in 4.3.x, but if backported, and
+# -fno-lax-vector-conversions is set, errors may occur with the intrinsics
+# files along with the older system includes, e.g., emmintrin.h.
+# Originally observed with cc (GCC) 4.2.1 20070831 patched [FreeBSD] (9.3).
+# https://bugs.chromium.org/p/webp/issues/detail?id=274
+AS_IF([test "$GCC" = "yes" ], [
+       case "$host_cpu" in
+         amd64|i?86|x86_64)
+           AC_COMPILE_IFELSE(
+             dnl only check for -flax-vector-conversions with older gcc, skip
+             dnl clang as it reports itself as 4.2.1, but the flag isn't needed.
+             [AC_LANG_SOURCE([#if !defined(__clang__) && defined(__GNUC__) && \
+                                  ((__GNUC__ << 8) | __GNUC_MINOR__) < 0x403
+                              #error old gcc
+                              #endif
+                              int main(void) { return 0; }
+                             ])],,
+              [TEST_AND_ADD_CFLAGS([INTRINSICS_CFLAGS],
+                                   [-flax-vector-conversions])])
+           ;;
+       esac])
 AC_SUBST([AM_CFLAGS])
 
+dnl === Check for machine specific flags
+AC_ARG_ENABLE([sse4.1],
+              AS_HELP_STRING([--disable-sse4.1],
+                             [Disable detection of SSE4.1 support
+                              @<:@default=auto@:>@]))
+
+AS_IF([test "x$enable_sse4_1" != "xno" -a "x$enable_sse2" != "xno"], [
+  SSE41_FLAGS="$INTRINSICS_CFLAGS $SSE41_FLAGS"
+  TEST_AND_ADD_CFLAGS([SSE41_FLAGS], [-msse4.1])
+  AS_IF([test -n "$SSE41_FLAGS"], [
+    SAVED_CFLAGS=$CFLAGS
+    CFLAGS="$CFLAGS $SSE41_FLAGS"
+    AC_CHECK_HEADER([smmintrin.h],
+                    [AC_DEFINE(WEBP_HAVE_SSE41, [1],
+                     [Set to 1 if SSE4.1 is supported])],
+                    [SSE41_FLAGS=""])
+    CFLAGS=$SAVED_CFLAGS])
+  AC_SUBST([SSE41_FLAGS])])
+
+AC_ARG_ENABLE([sse2],
+              AS_HELP_STRING([--disable-sse2],
+                             [Disable detection of SSE2 support
+                              @<:@default=auto@:>@]))
+
+AS_IF([test "x$enable_sse2" != "xno"], [
+  SSE2_FLAGS="$INTRINSICS_CFLAGS $SSE2_FLAGS"
+  TEST_AND_ADD_CFLAGS([SSE2_FLAGS], [-msse2])
+  AS_IF([test -n "$SSE2_FLAGS"], [
+    SAVED_CFLAGS=$CFLAGS
+    CFLAGS="$CFLAGS $SSE2_FLAGS"
+    AC_CHECK_HEADER([emmintrin.h],
+                    [AC_DEFINE(WEBP_HAVE_SSE2, [1],
+                     [Set to 1 if SSE2 is supported])],
+                    [SSE2_FLAGS=""])
+    CFLAGS=$SAVED_CFLAGS])
+  AC_SUBST([SSE2_FLAGS])])
+
+AC_ARG_ENABLE([neon],
+              AS_HELP_STRING([--disable-neon],
+                             [Disable detection of NEON support
+                              @<:@default=auto@:>@]))
+
+AC_ARG_ENABLE([neon_rtcd],
+              AS_HELP_STRING([--disable-neon-rtcd],
+                             [Disable runtime detection of NEON support via
+                              /proc/cpuinfo on Linux hosts
+                              @<:@default=auto@:>@]))
+# For ARM(7) hosts:
+# Both NEON flags unset and NEON support detected = build all modules with NEON
+# NEON detected with the use of -mfpu=neon = build only NEON modules with NEON
+AS_IF([test "x$enable_neon" != "xno"], [
+  case "$host_cpu" in
+    arm|armv7*)
+      # Test for NEON support without flags before falling back to -mfpu=neon
+      for flag in '' '-mfpu=neon'; do
+        LOCAL_NEON_FLAGS="$INTRINSICS_CFLAGS $NEON_FLAGS"
+        TEST_AND_ADD_CFLAGS([LOCAL_NEON_FLAGS], [$flag])
+        SAVED_CFLAGS=$CFLAGS
+        CFLAGS="$CFLAGS $LOCAL_NEON_FLAGS"
+
+        dnl Note AC_LANG_PROGRAM([]) uses an old-style main definition.
+        AC_COMPILE_IFELSE([AC_LANG_SOURCE([
+          #include <arm_neon.h>
+          int main(void) {
+            int8x8_t v = vdup_n_s8(0);
+            (void)v;
+            return 0;
+          }])],
+          [NEON_FLAGS="$(echo $LOCAL_NEON_FLAGS | $SED 's/^ *//')"
+           AS_IF([test -n "$NEON_FLAGS"], [
+             AS_IF([test "${host_os%%-*}" = "linux" -o \
+                         "x$enable_neon_rtcd" = "xno"], [
+               CFLAGS=$SAVED_CFLAGS
+               AC_DEFINE(WEBP_HAVE_NEON, [1], [Set to 1 if NEON is supported])
+               break
+             ],[
+               AC_MSG_WARN(m4_normalize([NEON runtime cpu-detection is
+                                         unavailable for ${host_os%%-*}. Force
+                                         with CFLAGS=-mfpu=neon or
+                                         --disable-neon-rtcd.]))
+               enable_neon_rtcd=no
+               NEON_FLAGS=""
+             ])
+           ],[
+             CFLAGS=$SAVED_CFLAGS
+             AC_DEFINE(WEBP_HAVE_NEON, [1], [Set to 1 if NEON is supported])
+             break
+           ])])
+        CFLAGS=$SAVED_CFLAGS
+      done
+
+      AS_IF([test -n "$NEON_FLAGS"], [
+        # If NEON is available and rtcd is disabled apply NEON_FLAGS globally.
+        AS_IF([test "x$enable_neon_rtcd" = "xno"], [
+          AM_CFLAGS="$AM_CFLAGS $NEON_FLAGS"
+          NEON_FLAGS=""],
+          [AC_DEFINE(WEBP_HAVE_NEON_RTCD, [1],
+                     [Set to 1 if runtime detection of NEON is enabled])])])
+
+      case "$host_os" in
+        *android*) AC_CHECK_HEADERS([cpu-features.h]) ;;
+      esac
+      ;;
+    aarch64*|arm64*)
+      AC_DEFINE(WEBP_HAVE_NEON, [1], [Set to 1 if NEON is supported])
+      ;;
+  esac
+  AC_SUBST([NEON_FLAGS])])
+
 dnl === CLEAR_LIBVARS([var_pfx])
 dnl ===   Clears <var_pfx>_{INCLUDES,LIBS}.
 AC_DEFUN([CLEAR_LIBVARS], [$1_INCLUDES=""; $1_LIBS=""])
@@ -93,6 +302,26 @@ AC_DEFUN([LIBCHECK_EPILOGUE],
           CPPFLAGS=$SAVED_CPPFLAGS
           LIBS=$SAVED_LIBS])
 
+dnl === Check for gcc builtins
+
+dnl === CHECK_FOR_BUILTIN([builtin], [param], [define])
+dnl ===   links a C AC_LANG_PROGRAM, with <builtin>(<param>)
+dnl ===   AC_DEFINE'ing <define> if successful.
+AC_DEFUN([CHECK_FOR_BUILTIN],
+         [AC_LANG_PUSH([C])
+          AC_MSG_CHECKING([for $1])
+          AC_LINK_IFELSE([AC_LANG_PROGRAM([], [(void)$1($2)])],
+                         [AC_MSG_RESULT([yes])
+                          AC_DEFINE([$3], [1],
+                                    [Set to 1 if $1 is available])],
+                         [AC_MSG_RESULT([no])]),
+          AC_LANG_POP])
+
+dnl AC_CHECK_FUNC doesn't work with builtin's.
+CHECK_FOR_BUILTIN([__builtin_bswap16], [1u << 15], [HAVE_BUILTIN_BSWAP16])
+CHECK_FOR_BUILTIN([__builtin_bswap32], [1u << 31], [HAVE_BUILTIN_BSWAP32])
+CHECK_FOR_BUILTIN([__builtin_bswap64], [1ull << 63], [HAVE_BUILTIN_BSWAP64])
+
 dnl === Check for pthread support
 AC_ARG_ENABLE([threading],
               AS_HELP_STRING([--disable-threading],
@@ -106,214 +335,338 @@ if test "$enable_threading" = "yes"; then
               CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
               CC="$PTHREAD_CC"
              ],
-             [enable_threading=no])
+             [AC_CHECK_FUNC([_beginthreadex],
+                            [AC_DEFINE([WEBP_USE_THREAD], [1],
+                                       [Undefine this to disable thread
+                                        support.])],
+                            [enable_threading=no])])
 fi
 AC_MSG_NOTICE([checking if threading is enabled... ${enable_threading-no}])
 
 dnl === check for OpenGL/GLUT support ===
-CLEAR_LIBVARS([GL])
-WITHLIB_OPTION([gl], [GL])
 
-LIBCHECK_PROLOGUE([GL])
+AC_ARG_ENABLE([gl], AS_HELP_STRING([--disable-gl],
+                                   [Disable detection of OpenGL support
+                                    @<:@default=auto@:>@]))
+AS_IF([test "x$enable_gl" != "xno"], [
+  CLEAR_LIBVARS([GL])
+  WITHLIB_OPTION([gl], [GL])
 
-glut_cflags="none"
-glut_ldflags="none"
-case $host_os in
-  darwin*)
-    # Special case for OSX builds. Append these to give the user a chance to
-    # override with --with-gl*
-    glut_cflags="$glut_cflags|-framework GLUT -framework OpenGL"
-    glut_ldflags="$glut_ldflags|-framework GLUT -framework OpenGL"
-    ;;
-esac
+  LIBCHECK_PROLOGUE([GL])
 
-GLUT_SAVED_CPPFLAGS="$CPPFLAGS"
-SAVED_IFS="$IFS"
-IFS="|"
-for flag in $glut_cflags; do
-  # restore IFS immediately as the autoconf macros may need the default.
-  IFS="$SAVED_IFS"
-  unset ac_cv_header_GL_glut_h
-  unset ac_cv_header_OpenGL_glut_h
-
-  case $flag in
-    none) ;;
-    *) CPPFLAGS="$flag $CPPFLAGS";;
+  glut_cflags="none"
+  glut_ldflags="none"
+  case $host_os in
+    darwin*)
+      # Special case for OSX builds. Append these to give the user a chance to
+      # override with --with-gl*
+      glut_cflags="$glut_cflags|-framework GLUT -framework OpenGL"
+      glut_ldflags="$glut_ldflags|-framework GLUT -framework OpenGL"
+      # quiet deprecation warnings for glut
+      TEST_AND_ADD_CFLAGS([AM_CFLAGS], [-Wno-deprecated-declarations])
+      ;;
   esac
-  AC_CHECK_HEADERS([GL/glut.h GLUT/glut.h OpenGL/glut.h],
-                   [glut_headers=yes;
-                    test "$flag" = "none" || GL_INCLUDES="$CPPFLAGS";
-                    break])
-  CPPFLAGS="$GLUT_SAVED_CPPFLAGS"
-  test "$glut_headers" = "yes" && break
-done
-IFS="$SAVED_IFS"
 
-if test "$glut_headers" = "yes"; then
-  AC_LANG_PUSH([C])
-  GLUT_SAVED_LDFLAGS="$LDFLAGS"
+  GLUT_SAVED_CPPFLAGS="$CPPFLAGS"
   SAVED_IFS="$IFS"
   IFS="|"
-  for flag in $glut_ldflags; do
+  for flag in $glut_cflags; do
     # restore IFS immediately as the autoconf macros may need the default.
     IFS="$SAVED_IFS"
-    unset ac_cv_search_glBegin
+    unset ac_cv_header_GL_glut_h
+    unset ac_cv_header_OpenGL_glut_h
 
     case $flag in
       none) ;;
-      *) LDFLAGS="$flag $LDFLAGS";;
+      *) CPPFLAGS="$flag $CPPFLAGS";;
     esac
+    AC_CHECK_HEADERS([GL/glut.h GLUT/glut.h OpenGL/glut.h],
+                     [glut_headers=yes;
+                      test "$flag" = "none" || GL_INCLUDES="$CPPFLAGS";
+                      break])
+    CPPFLAGS="$GLUT_SAVED_CPPFLAGS"
+    test "$glut_headers" = "yes" && break
+  done
+  IFS="$SAVED_IFS"
 
-    # find libGL
-    GL_SAVED_LIBS="$LIBS"
-    AC_SEARCH_LIBS([glBegin], [GL OpenGL])
-    LIBS="$GL_SAVED_LIBS"
+  if test "$glut_headers" = "yes"; then
+    AC_LANG_PUSH([C])
+    GLUT_SAVED_LDFLAGS="$LDFLAGS"
+    SAVED_IFS="$IFS"
+    IFS="|"
+    for flag in $glut_ldflags; do
+      # restore IFS immediately as the autoconf macros may need the default.
+      IFS="$SAVED_IFS"
+      unset ac_cv_search_glBegin
 
-    # A direct link to libGL may not be necessary on e.g., linux.
-    GLUT_SAVED_LIBS="$LIBS"
-    for lib in "" "-lglut" "-lglut $ac_cv_search_glBegin"; do
-      LIBS="$lib"
+      case $flag in
+        none) ;;
+        *) LDFLAGS="$flag $LDFLAGS";;
+      esac
+
+      # find libGL
+      GL_SAVED_LIBS="$LIBS"
+      AC_SEARCH_LIBS([glBegin], [GL OpenGL opengl32])
+      LIBS="$GL_SAVED_LIBS"
+
+      # A direct link to libGL may not be necessary on e.g., linux.
+      GLUT_SAVED_LIBS="$LIBS"
+      for lib in "" "-lglut" "-lglut $ac_cv_search_glBegin"; do
+        LIBS="$lib"
+        AC_LINK_IFELSE(
+          [AC_LANG_PROGRAM([
+             #ifdef __cplusplus
+             # define EXTERN_C extern "C"
+             #else
+             # define EXTERN_C
+             #endif
+             EXTERN_C char glOrtho();
+             EXTERN_C char glutMainLoop();
+            ],[
+             glOrtho();
+             glutMainLoop();
+            ])
+          ],
+          AC_DEFINE(WEBP_HAVE_GL, [1],
+                    [Set to 1 if OpenGL is supported])
+          [glut_support=yes], []
+        )
+        if test "$glut_support" = "yes"; then
+          GL_LIBS="$LDFLAGS $lib"
+          break
+        fi
+      done
+      LIBS="$GLUT_SAVED_LIBS"
+      LDFLAGS="$GLUT_SAVED_LDFLAGS"
+      test "$glut_support" = "yes" && break
+    done
+    IFS="$SAVED_IFS"
+    AC_LANG_POP
+  fi
+
+  LIBCHECK_EPILOGUE([GL])
+
+  if test "$glut_support" = "yes" -a "$enable_libwebpdemux" = "yes"; then
+    build_vwebp=yes
+  else
+    AC_MSG_NOTICE(
+      m4_normalize([Not building vwebp.
+                    OpenGL libraries and --enable-libwebpdemux are required.]))
+  fi
+])
+AM_CONDITIONAL([BUILD_VWEBP], [test "$build_vwebp" = "yes"])
+
+dnl === check for SDL support ===
+
+AC_ARG_ENABLE([sdl],
+              AS_HELP_STRING([--disable-sdl],
+                             [Disable detection of SDL support
+                              @<:@default=auto@:>@]))
+AS_IF([test "x$enable_sdl" != "xno"], [
+  CLEAR_LIBVARS([SDL])
+  AC_PATH_PROGS([LIBSDL_CONFIG], [sdl-config])
+  if test -n "$LIBSDL_CONFIG"; then
+    SDL_INCLUDES=`$LIBSDL_CONFIG --cflags`
+    SDL_LIBS="`$LIBSDL_CONFIG --libs`"
+  fi
+
+  WITHLIB_OPTION([sdl], [SDL])
+
+  sdl_header="no"
+  LIBCHECK_PROLOGUE([SDL])
+  AC_CHECK_HEADER([SDL/SDL.h], [sdl_header="SDL/SDL.h"],
+                  [AC_CHECK_HEADER([SDL.h], [sdl_header="SDL.h"],
+                  [AC_MSG_WARN(SDL library not available - no sdl.h)])])
+  if test x"$sdl_header" != "xno"; then
+    AC_LANG_PUSH(C)
+    SDL_SAVED_LIBS="$LIBS"
+    for lib in "" "-lSDL" "-lSDLmain -lSDL"; do
+      LIBS="$SDL_SAVED_LIBS $lib"
+      # Perform a full link to ensure SDL_main is resolved if needed.
       AC_LINK_IFELSE(
-        [AC_LANG_PROGRAM([
-           #ifdef __cplusplus
-           # define EXTERN_C extern "C"
-           #else
-           # define EXTERN_C
-           #endif
-           EXTERN_C char glOrtho();
-           EXTERN_C char glutMainLoop();
-          ],[
-           glOrtho();
-           glutMainLoop();
-          ])
-        ],
-        AC_DEFINE(WEBP_HAVE_GL, [1],
-                  [Set to 1 if OpenGL is supported])
-        [glut_support=yes], []
+        [AC_LANG_SOURCE([
+           #include <$sdl_header>
+           int main(int argc, char** argv) {
+             SDL_Init(0);
+             return 0;
+           }])],
+        [SDL_LIBS="$LDFLAGS $LIBS"
+         SDL_INCLUDES="$SDL_INCLUDES -DWEBP_HAVE_SDL"
+         AC_DEFINE(WEBP_HAVE_SDL, [1],
+                   [Set to 1 if SDL library is installed])
+         sdl_support=yes]
       )
-      if test "$glut_support" = "yes"; then
-        GL_LIBS="$LDFLAGS $lib"
+      if test x"$sdl_support" = "xyes"; then
         break
       fi
     done
-    LIBS="$GLUT_SAVED_LIBS"
-    LDFLAGS="$GLUT_SAVED_LDFLAGS"
-    test "$glut_support" = "yes" && break
-  done
-  IFS="$SAVED_IFS"
-  AC_LANG_POP
-fi
+    # LIBS is restored by LIBCHECK_EPILOGUE
+    AC_LANG_POP
+    if test x"$sdl_header" = "xSDL.h"; then
+      SDL_INCLUDES="$SDL_INCLUDES -DWEBP_HAVE_JUST_SDL_H"
+    fi
+  fi
+  LIBCHECK_EPILOGUE([SDL])
 
-LIBCHECK_EPILOGUE([GL])
+  if test x"$sdl_support" = "xyes"; then
+    build_vwebp_sdl=yes
+  else
+    AC_MSG_NOTICE([Not building vwebp-sdl. SDL library is required.])
+  fi
+])
 
-if test "$glut_support" = "yes" -a "$enable_libwebpdemux" = "yes"; then
-  build_vwebp=yes
-fi
-AM_CONDITIONAL([BUILD_VWEBP], [test "$build_vwebp" = "yes"])
+AM_CONDITIONAL([BUILD_VWEBP_SDL], [test "$build_vwebp_sdl" = "yes"])
 
 dnl === check for PNG support ===
 
-CLEAR_LIBVARS([PNG])
-AC_PATH_PROGS(LIBPNG_CONFIG,
-              [libpng-config libpng15-config libpng14-config libpng12-config])
-if test -n "$LIBPNG_CONFIG"; then
-  PNG_INCLUDES=`$LIBPNG_CONFIG --cflags`
-  PNG_PREFIX=`$LIBPNG_CONFIG --prefix`
-  if test "${PNG_PREFIX}/lib" != "/usr/lib" ; then
-    PNG_LIBS="-L${PNG_PREFIX}/lib"
+AC_ARG_ENABLE([png], AS_HELP_STRING([--disable-png],
+                                    [Disable detection of PNG format support
+                                     @<:@default=auto@:>@]))
+AS_IF([test "x$enable_png" != "xno"], [
+  CLEAR_LIBVARS([PNG])
+  AC_PATH_PROGS([LIBPNG_CONFIG],
+                [libpng-config libpng16-config libpng15-config libpng14-config \
+                 libpng12-config])
+  if test -n "$LIBPNG_CONFIG"; then
+    PNG_INCLUDES=`$LIBPNG_CONFIG --cflags`
+    PNG_LIBS="`$LIBPNG_CONFIG --ldflags`"
   fi
-  PNG_LIBS="$PNG_LIBS `$LIBPNG_CONFIG --libs`"
-fi
 
-WITHLIB_OPTION([png], [PNG])
+  WITHLIB_OPTION([png], [PNG])
 
-LIBCHECK_PROLOGUE([PNG])
-AC_CHECK_HEADER(png.h,
-  AC_SEARCH_LIBS(png_get_libpng_ver, [png],
-                 [test "$ac_cv_search_png_get_libpng_ver" = "none required" \
-                    || PNG_LIBS="$PNG_LIBS $ac_cv_search_png_get_libpng_ver"
-                  PNG_INCLUDES="$PNG_INCLUDES -DWEBP_HAVE_PNG"
-                  AC_DEFINE(WEBP_HAVE_PNG, [1],
-                            [Set to 1 if PNG library is installed])
-                  png_support=yes
-                 ],
-                 [AC_MSG_WARN(Optional png library not found)
-                  PNG_LIBS=""
-                  PNG_INCLUDES=""
-                 ],
-                 [$MATH_LIBS]),
-  [AC_MSG_WARN(png library not available - no png.h)
-   PNG_LIBS=""
-   PNG_INCLUDES=""
-  ],
-)
-LIBCHECK_EPILOGUE([PNG])
+  LIBCHECK_PROLOGUE([PNG])
+  AC_CHECK_HEADER(png.h,
+    AC_SEARCH_LIBS(png_get_libpng_ver, [png],
+                   [test "$ac_cv_search_png_get_libpng_ver" = "none required" \
+                      || PNG_LIBS="$PNG_LIBS $ac_cv_search_png_get_libpng_ver"
+                    PNG_INCLUDES="$PNG_INCLUDES -DWEBP_HAVE_PNG"
+                    AC_DEFINE(WEBP_HAVE_PNG, [1],
+                              [Set to 1 if PNG library is installed])
+                    png_support=yes
+                   ],
+                   [AC_MSG_WARN(Optional png library not found)
+                    PNG_LIBS=""
+                    PNG_INCLUDES=""
+                   ],
+                   [$MATH_LIBS]),
+    [AC_MSG_WARN(png library not available - no png.h)
+     PNG_LIBS=""
+     PNG_INCLUDES=""
+    ],
+  )
+  LIBCHECK_EPILOGUE([PNG])
+])
 
 dnl === check for JPEG support ===
 
-CLEAR_LIBVARS([JPEG])
-WITHLIB_OPTION([jpeg], [JPEG])
+AC_ARG_ENABLE([jpeg],
+              AS_HELP_STRING([--disable-jpeg],
+                             [Disable detection of JPEG format support
+                              @<:@default=auto@:>@]))
+AS_IF([test "x$enable_jpeg" != "xno"], [
+  CLEAR_LIBVARS([JPEG])
+  WITHLIB_OPTION([jpeg], [JPEG])
 
-LIBCHECK_PROLOGUE([JPEG])
-AC_CHECK_HEADER(jpeglib.h,
-  AC_CHECK_LIB(jpeg, jpeg_set_defaults,
-               [JPEG_LIBS="$JPEG_LIBS -ljpeg"
-                JPEG_INCLUDES="$JPEG_INCLUDES -DWEBP_HAVE_JPEG"
-                AC_DEFINE(WEBP_HAVE_JPEG, [1],
-                          [Set to 1 if JPEG library is installed])
-                jpeg_support=yes
-               ],
-               AC_MSG_WARN(Optional jpeg library not found),
-               [$MATH_LIBS]),
-  AC_MSG_WARN(jpeg library not available - no jpeglib.h)
-)
-LIBCHECK_EPILOGUE([JPEG])
+  LIBCHECK_PROLOGUE([JPEG])
+  AC_CHECK_HEADER(jpeglib.h,
+    AC_CHECK_LIB(jpeg, jpeg_set_defaults,
+                 [JPEG_LIBS="$JPEG_LIBS -ljpeg"
+                  JPEG_INCLUDES="$JPEG_INCLUDES -DWEBP_HAVE_JPEG"
+                  AC_DEFINE(WEBP_HAVE_JPEG, [1],
+                            [Set to 1 if JPEG library is installed])
+                  jpeg_support=yes
+                 ],
+                 AC_MSG_WARN(Optional jpeg library not found),
+                 [$MATH_LIBS]),
+    AC_MSG_WARN(jpeg library not available - no jpeglib.h)
+  )
+  LIBCHECK_EPILOGUE([JPEG])
+])
 
 dnl === check for TIFF support ===
 
-CLEAR_LIBVARS([TIFF])
-WITHLIB_OPTION([tiff], [TIFF])
+AC_ARG_ENABLE([tiff],
+              AS_HELP_STRING([--disable-tiff],
+                             [Disable detection of TIFF format support
+                              @<:@default=auto@:>@]))
+AS_IF([test "x$enable_tiff" != "xno"], [
+  CLEAR_LIBVARS([TIFF])
+  WITHLIB_OPTION([tiff], [TIFF])
 
-LIBCHECK_PROLOGUE([TIFF])
-AC_CHECK_HEADER(tiffio.h,
-  AC_CHECK_LIB(tiff, TIFFGetVersion,
-               [TIFF_LIBS="$TIFF_LIBS -ltiff"
-                TIFF_INCLUDES="$TIFF_INCLUDES -DWEBP_HAVE_TIFF"
-                AC_DEFINE(WEBP_HAVE_TIFF, [1],
-                          [Set to 1 if TIFF library is installed])
-                tiff_support=yes
-               ],
-               AC_MSG_WARN(Optional tiff library not found),
-               [$MATH_LIBS]),
-  AC_MSG_WARN(tiff library not available - no tiffio.h)
-)
-LIBCHECK_EPILOGUE([TIFF])
+  LIBCHECK_PROLOGUE([TIFF])
+  AC_CHECK_HEADER(tiffio.h,
+    AC_CHECK_LIB(tiff, TIFFGetVersion,
+                 [TIFF_LIBS="$TIFF_LIBS -ltiff"
+                  TIFF_INCLUDES="$TIFF_INCLUDES -DWEBP_HAVE_TIFF"
+                  AC_DEFINE(WEBP_HAVE_TIFF, [1],
+                            [Set to 1 if TIFF library is installed])
+                  tiff_support=yes
+                 ],
+                 AC_MSG_WARN(Optional tiff library not found),
+                 [$MATH_LIBS]),
+    AC_MSG_WARN(tiff library not available - no tiffio.h)
+  )
+  LIBCHECK_EPILOGUE([TIFF])
+])
 
 dnl === check for GIF support ===
 
-CLEAR_LIBVARS([GIF])
-WITHLIB_OPTION([gif], [GIF])
+AC_ARG_ENABLE([gif], AS_HELP_STRING([--disable-gif],
+                                    [Disable detection of GIF format support
+                                     @<:@default=auto@:>@]))
+AS_IF([test "x$enable_gif" != "xno"], [
+  CLEAR_LIBVARS([GIF])
+  WITHLIB_OPTION([gif], [GIF])
 
-LIBCHECK_PROLOGUE([GIF])
-AC_CHECK_HEADER(gif_lib.h,
-  AC_CHECK_LIB([gif], [DGifOpenFileHandle],
-               [GIF_LIBS="$GIF_LIBS -lgif"
-                AC_DEFINE(WEBP_HAVE_GIF, [1],
-                          [Set to 1 if GIF library is installed])
-                gif_support=yes
-               ],
-               AC_MSG_WARN(Optional gif library not found),
-               [$MATH_LIBS]),
-  AC_MSG_WARN(gif library not available - no gif_lib.h)
-)
-LIBCHECK_EPILOGUE([GIF])
+  LIBCHECK_PROLOGUE([GIF])
+  AC_CHECK_HEADER(gif_lib.h,
+    AC_CHECK_LIB([gif], [DGifOpenFileHandle],
+                 [GIF_LIBS="$GIF_LIBS -lgif"
+                  AC_DEFINE(WEBP_HAVE_GIF, [1],
+                            [Set to 1 if GIF library is installed])
+                  gif_support=yes
+                 ],
+                 AC_MSG_WARN(Optional gif library not found),
+                 [$MATH_LIBS]),
+    AC_MSG_WARN(gif library not available - no gif_lib.h)
+  )
+  LIBCHECK_EPILOGUE([GIF])
 
-if test "$gif_support" = "yes" -a \
-        "$enable_libwebpmux" = "yes"; then
-  build_gif2webp=yes
-fi
+  if test "$gif_support" = "yes" -a \
+          "$enable_libwebpdemux" = "yes"; then
+    build_anim_diff=yes
+  else
+    AC_MSG_NOTICE(
+      [Not building anim_diff. libgif and --enable-libwebpdemux are required.])
+  fi
+
+  if test "$gif_support" = "yes" -a \
+          "$enable_libwebpmux" = "yes"; then
+    build_gif2webp=yes
+  else
+    AC_MSG_NOTICE(
+      [Not building gif2webp. libgif and --enable-libwebpmux are required.])
+  fi
+])
+AM_CONDITIONAL([BUILD_ANIMDIFF], [test "${build_anim_diff}" = "yes"])
 AM_CONDITIONAL([BUILD_GIF2WEBP], [test "${build_gif2webp}" = "yes"])
 
+if test "$enable_libwebpdemux" = "yes" -a "$enable_libwebpmux" = "yes"; then
+  build_img2webp=yes
+else
+  AC_MSG_NOTICE(
+    m4_normalize([Not building img2webp.
+                  --enable-libwebpdemux & --enable-libwebpmux are required.]))
+fi
+AM_CONDITIONAL([BUILD_IMG2WEBP], [test "${build_img2webp}" = "yes"])
+
+if test "$enable_libwebpmux" = "yes"; then
+  build_webpinfo=yes
+else
+  AC_MSG_NOTICE([Not building webpinfo. --enable-libwebpdemux is required.])
+fi
+AM_CONDITIONAL([BUILD_WEBPINFO], [test "${build_webpinfo}" = "yes"])
+
 dnl === check for WIC support ===
 
 AC_ARG_ENABLE([wic],
@@ -322,7 +675,9 @@ AC_ARG_ENABLE([wic],
                               @<:@default=auto@:>@]),,
               [enable_wic=yes])
 
-if test "$target_os" = "mingw32" -a "$enable_wic" = "yes"; then
+case $host_os in
+mingw*)
+if test "$enable_wic" = "yes"; then
   AC_CHECK_HEADERS([wincodec.h shlwapi.h windows.h])
   if test "$ac_cv_header_wincodec_h" = "yes"; then
     AC_MSG_CHECKING(for Windows Imaging Component support)
@@ -362,8 +717,9 @@ if test "$target_os" = "mingw32" -a "$enable_wic" = "yes"; then
     AC_MSG_RESULT(${wic_support-no})
   fi
 fi
+esac
 
-dnl === If --enable-swap-16bit-csp is defined, add -DWEBP_SWAP_16BIT_CSP
+dnl === If --enable-swap-16bit-csp is defined, add -DWEBP_SWAP_16BIT_CSP=1
 
 USE_SWAP_16BIT_CSP=""
 AC_MSG_CHECKING(if --enable-swap-16bit-csp option is specified)
@@ -371,55 +727,34 @@ AC_ARG_ENABLE([swap-16bit-csp],
               AS_HELP_STRING([--enable-swap-16bit-csp],
                              [Enable byte swap for 16 bit colorspaces]))
 if test "$enable_swap_16bit_csp" = "yes"; then
-  USE_SWAP_16BIT_CSP="-DWEBP_SWAP_16BIT_CSP"
+  USE_SWAP_16BIT_CSP="-DWEBP_SWAP_16BIT_CSP=1"
 fi
 AC_MSG_RESULT(${enable_swap_16bit_csp-no})
 AC_SUBST(USE_SWAP_16BIT_CSP)
 
-dnl === If --enable-experimental is defined, add -DWEBP_EXPERIMENTAL_FEATURES
+dnl === If --disable-near-lossless is defined, add -DWEBP_NEAR_LOSSLESS=0
 
-USE_EXPERIMENTAL_CODE=""
-AC_MSG_CHECKING(if --enable-experimental option is specified)
-AC_ARG_ENABLE([experimental], AS_HELP_STRING([--enable-experimental],
-                                             [Activate experimental features]))
-if test "$enable_experimental" = "yes"; then
-  AC_DEFINE(WEBP_EXPERIMENTAL_FEATURES, [1], [Enable experimental code])
-  USE_EXPERIMENTAL_CODE="-DWEBP_EXPERIMENTAL_FEATURES"
+AC_DEFINE(WEBP_NEAR_LOSSLESS, [1], [Enable near lossless encoding])
+AC_MSG_CHECKING(if --disable-near-lossless option is specified)
+AC_ARG_ENABLE([near_lossless],
+              AS_HELP_STRING([--disable-near-lossless],
+                             [Disable near lossless encoding]),
+              [], [enable_near_lossless=yes])
+if test "$enable_near_lossless" = "no"; then
+  AC_DEFINE(WEBP_NEAR_LOSSLESS, [0], [Enable near lossless encoding])
+  AC_MSG_RESULT([yes])
+else
+  AC_MSG_RESULT([no])
 fi
-AC_MSG_RESULT(${enable_experimental-no})
-AC_SUBST(USE_EXPERIMENTAL_CODE)
-
-dnl === Check whether libwebpmux should be built
-AC_MSG_CHECKING(whether libwebpmux is to be built)
-AC_ARG_ENABLE([libwebpmux],
-              AS_HELP_STRING([--enable-libwebpmux],
-                             [Build libwebpmux @<:@default=no@:>@]))
-AC_MSG_RESULT(${enable_libwebpmux-no})
-AM_CONDITIONAL([WANT_MUX], [test "$enable_libwebpmux" = "yes"])
-
-dnl === Check whether libwebpdemux should be built
-AC_MSG_CHECKING(whether libwebpdemux is to be built)
-AC_ARG_ENABLE([libwebpdemux],
-              AS_HELP_STRING([--enable-libwebpdemux],
-                             [Build libwebpdemux @<:@default=no@:>@]))
-AC_MSG_RESULT(${enable_libwebpdemux-no})
-AM_CONDITIONAL([WANT_DEMUX], [test "$enable_libwebpdemux" = "yes"])
-
-dnl === Check whether decoder library should be built.
-AC_MSG_CHECKING(whether decoder library is to be built)
-AC_ARG_ENABLE([libwebpdecoder],
-              AS_HELP_STRING([--enable-libwebpdecoder],
-                             [Build libwebpdecoder @<:@default=no@:>@]))
-AC_MSG_RESULT(${enable_libwebpdecoder-no})
-AM_CONDITIONAL([BUILD_LIBWEBPDECODER], [test "$enable_libwebpdecoder" = "yes"])
 
 dnl =========================
 
 AC_CONFIG_MACRO_DIR([m4])
-AC_CONFIG_HEADERS([config.h])
+AC_CONFIG_HEADERS([src/webp/config.h])
 AC_CONFIG_FILES([Makefile src/Makefile man/Makefile \
-                 examples/Makefile src/dec/Makefile \
-                 src/enc/Makefile src/dsp/Makefile \
+                 examples/Makefile extras/Makefile imageio/Makefile \
+                 sharpyuv/Makefile \
+                 src/dec/Makefile src/enc/Makefile src/dsp/Makefile \
                  src/demux/Makefile src/mux/Makefile \
                  src/utils/Makefile \
                  src/libwebp.pc src/libwebpdecoder.pc \
@@ -434,27 +769,33 @@ WebP Configuration Summary
 
 Shared libraries: ${enable_shared}
 Static libraries: ${enable_static}
-Threaded decode: ${enable_threading-no}
+Threading support: ${enable_threading-no}
 libwebp: yes
 libwebpdecoder: ${enable_libwebpdecoder-no}
 libwebpdemux: ${enable_libwebpdemux-no}
 libwebpmux: ${enable_libwebpmux-no}
+libwebpextras: ${enable_libwebpextras-no}
 
 Tools:
-cwebp : yes
+cwebp : ${enable_libwebpdemux-no}
   Input format support
   ====================
   JPEG : ${jpeg_support-no}
   PNG  : ${png_support-no}
   TIFF : ${tiff_support-no}
   WIC  : ${wic_support-no}
-dwebp : yes
+dwebp : ${enable_libwebpdemux-no}
   Output format support
   =====================
   PNG  : ${png_support-no}
   WIC  : ${wic_support-no}
 GIF support : ${gif_support-no}
+anim_diff   : ${build_anim_diff-no}
 gif2webp    : ${build_gif2webp-no}
+img2webp    : ${build_img2webp-no}
 webpmux     : ${enable_libwebpmux-no}
 vwebp       : ${build_vwebp-no}
+webpinfo    : ${build_webpinfo-no}
+SDL support : ${sdl_support-no}
+vwebp_sdl   : ${build_vwebp_sdl-no}
 ])

doc/README

@@ -1,29 +0,0 @@
-
-Generate libwebp Container Spec Docs from Text Source
-=====================================================
-
-HTML generation requires kramdown [1], easily installed as a
-rubygem [2].  Rubygems installation should satisfy dependencies
-automatically.
-
-[1]: http://kramdown.rubyforge.org/
-[2]: http://rubygems.org/
-
-HTML generation can then be done from the project root:
-
-$ kramdown doc/webp-container-spec.txt --template doc/template.html > \
-  doc/output/webp-container-spec.html
-
-kramdown can optionally syntax highlight code blocks, using CodeRay [3],
-a dependency of kramdown that rubygems will install automatically.  The
-following will apply inline CSS styling; an external stylesheet is not
-needed.
-
-$ kramdown doc/webp-lossless-bitstream-spec.txt --template \
-  doc/template.html --coderay-css style --coderay-line-numbers ' ' \
-  --coderay-default-lang c > \
-  doc/output/webp-lossless-bitstream-spec.html
-
-Optimally, use kramdown 0.13.7 or newer if syntax highlighting desired.
-
-[3]: http://coderay.rubychan.de/

doc/api.md

@@ -0,0 +1,385 @@
+# WebP APIs
+
+## Encoding API
+
+The main encoding functions are available in the header src/webp/encode.h
+
+The ready-to-use ones are:
+
+```c
+size_t WebPEncodeRGB(const uint8_t* rgb, int width, int height, int stride,
+                     float quality_factor, uint8_t** output);
+size_t WebPEncodeBGR(const uint8_t* bgr, int width, int height, int stride,
+                     float quality_factor, uint8_t** output);
+size_t WebPEncodeRGBA(const uint8_t* rgba, int width, int height, int stride,
+                      float quality_factor, uint8_t** output);
+size_t WebPEncodeBGRA(const uint8_t* bgra, int width, int height, int stride,
+                      float quality_factor, uint8_t** output);
+```
+
+They will convert raw RGB samples to a WebP data. The only control supplied is
+the quality factor.
+
+There are some variants for using the lossless format:
+
+```c
+size_t WebPEncodeLosslessRGB(const uint8_t* rgb, int width, int height,
+                             int stride, uint8_t** output);
+size_t WebPEncodeLosslessBGR(const uint8_t* bgr, int width, int height,
+                             int stride, uint8_t** output);
+size_t WebPEncodeLosslessRGBA(const uint8_t* rgba, int width, int height,
+                              int stride, uint8_t** output);
+size_t WebPEncodeLosslessBGRA(const uint8_t* bgra, int width, int height,
+                              int stride, uint8_t** output);
+```
+
+Of course in this case, no quality factor is needed since the compression occurs
+without loss of the input values, at the expense of larger output sizes.
+
+### Advanced encoding API
+
+A more advanced API is based on the WebPConfig and WebPPicture structures.
+
+WebPConfig contains the encoding settings and is not tied to a particular
+picture. WebPPicture contains input data, on which some WebPConfig will be used
+for compression. The encoding flow looks like:
+
+```c
+#include <webp/encode.h>
+
+// Setup a config, starting form a preset and tuning some additional
+// parameters
+WebPConfig config;
+if (!WebPConfigPreset(&config, WEBP_PRESET_PHOTO, quality_factor)) {
+  return 0;   // version error
+}
+// ... additional tuning
+config.sns_strength = 90;
+config.filter_sharpness = 6;
+config_error = WebPValidateConfig(&config);  // not mandatory, but useful
+
+// Setup the input data
+WebPPicture pic;
+if (!WebPPictureInit(&pic)) {
+  return 0;  // version error
+}
+pic.width = width;
+pic.height = height;
+// allocated picture of dimension width x height
+if (!WebPPictureAlloc(&pic)) {
+  return 0;   // memory error
+}
+// at this point, 'pic' has been initialized as a container,
+// and can receive the Y/U/V samples.
+// Alternatively, one could use ready-made import functions like
+// WebPPictureImportRGB(), which will take care of memory allocation.
+// In any case, past this point, one will have to call
+// WebPPictureFree(&pic) to reclaim memory.
+
+// Set up a byte-output write method. WebPMemoryWriter, for instance.
+WebPMemoryWriter wrt;
+WebPMemoryWriterInit(&wrt);     // initialize 'wrt'
+
+pic.writer = MyFileWriter;
+pic.custom_ptr = my_opaque_structure_to_make_MyFileWriter_work;
+
+// Compress!
+int ok = WebPEncode(&config, &pic);   // ok = 0 => error occurred!
+WebPPictureFree(&pic);  // must be called independently of the 'ok' result.
+
+// output data should have been handled by the writer at that point.
+// -> compressed data is the memory buffer described by wrt.mem / wrt.size
+
+// deallocate the memory used by compressed data
+WebPMemoryWriterClear(&wrt);
+```
+
+## Decoding API
+
+This is mainly just one function to call:
+
+```c
+#include "webp/decode.h"
+uint8_t* WebPDecodeRGB(const uint8_t* data, size_t data_size,
+                       int* width, int* height);
+```
+
+Please have a look at the file src/webp/decode.h for the details. There are
+variants for decoding in BGR/RGBA/ARGB/BGRA order, along with decoding to raw
+Y'CbCr samples. One can also decode the image directly into a pre-allocated
+buffer.
+
+To detect a WebP file and gather the picture's dimensions, the function:
+
+```c
+int WebPGetInfo(const uint8_t* data, size_t data_size,
+                int* width, int* height);
+```
+
+is supplied. No decoding is involved when using it.
+
+### Incremental decoding API
+
+In the case when data is being progressively transmitted, pictures can still be
+incrementally decoded using a slightly more complicated API. Decoder state is
+stored into an instance of the WebPIDecoder object. This object can be created
+with the purpose of decoding either RGB or Y'CbCr samples. For instance:
+
+```c
+WebPDecBuffer buffer;
+WebPInitDecBuffer(&buffer);
+buffer.colorspace = MODE_BGR;
+...
+WebPIDecoder* idec = WebPINewDecoder(&buffer);
+```
+
+As data is made progressively available, this incremental-decoder object can be
+used to decode the picture further. There are two (mutually exclusive) ways to
+pass freshly arrived data:
+
+either by appending the fresh bytes:
+
+```c
+WebPIAppend(idec, fresh_data, size_of_fresh_data);
+```
+
+or by just mentioning the new size of the transmitted data:
+
+```c
+WebPIUpdate(idec, buffer, size_of_transmitted_buffer);
+```
+
+Note that 'buffer' can be modified between each call to WebPIUpdate, in
+particular when the buffer is resized to accommodate larger data.
+
+These functions will return the decoding status: either VP8_STATUS_SUSPENDED if
+decoding is not finished yet or VP8_STATUS_OK when decoding is done. Any other
+status is an error condition.
+
+The 'idec' object must always be released (even upon an error condition) by
+calling: WebPDelete(idec).
+
+To retrieve partially decoded picture samples, one must use the corresponding
+method: WebPIDecGetRGB or WebPIDecGetYUVA. It will return the last displayable
+pixel row.
+
+Lastly, note that decoding can also be performed into a pre-allocated pixel
+buffer. This buffer must be passed when creating a WebPIDecoder, calling
+WebPINewRGB() or WebPINewYUVA().
+
+Please have a look at the src/webp/decode.h header for further details.
+
+### Advanced Decoding API
+
+WebP decoding supports an advanced API which provides on-the-fly cropping and
+rescaling, something of great usefulness on memory-constrained environments like
+mobile phones. Basically, the memory usage will scale with the output's size,
+not the input's, when one only needs a quick preview or a zoomed in portion of
+an otherwise too-large picture. Some CPU can be saved too, incidentally.
+
+```c
+// A) Init a configuration object
+WebPDecoderConfig config;
+CHECK(WebPInitDecoderConfig(&config));
+
+// B) optional: retrieve the bitstream's features.
+CHECK(WebPGetFeatures(data, data_size, &config.input) == VP8_STATUS_OK);
+
+// C) Adjust 'config' options, if needed
+config.options.no_fancy_upsampling = 1;
+config.options.use_scaling = 1;
+config.options.scaled_width = scaledWidth();
+config.options.scaled_height = scaledHeight();
+// etc.
+
+// D) Specify 'config' output options for specifying output colorspace.
+// Optionally the external image decode buffer can also be specified.
+config.output.colorspace = MODE_BGRA;
+// Optionally, the config.output can be pointed to an external buffer as
+// well for decoding the image. This externally supplied memory buffer
+// should be big enough to store the decoded picture.
+config.output.u.RGBA.rgba = (uint8_t*) memory_buffer;
+config.output.u.RGBA.stride = scanline_stride;
+config.output.u.RGBA.size = total_size_of_the_memory_buffer;
+config.output.is_external_memory = 1;
+
+// E) Decode the WebP image. There are two variants w.r.t decoding image.
+// The first one (E.1) decodes the full image and the second one (E.2) is
+// used to incrementally decode the image using small input buffers.
+// Any one of these steps can be used to decode the WebP image.
+
+// E.1) Decode full image.
+CHECK(WebPDecode(data, data_size, &config) == VP8_STATUS_OK);
+
+// E.2) Decode image incrementally.
+WebPIDecoder* const idec = WebPIDecode(NULL, NULL, &config);
+CHECK(idec != NULL);
+while (bytes_remaining > 0) {
+  VP8StatusCode status = WebPIAppend(idec, input, bytes_read);
+  if (status == VP8_STATUS_OK || status == VP8_STATUS_SUSPENDED) {
+    bytes_remaining -= bytes_read;
+  } else {
+    break;
+  }
+}
+WebPIDelete(idec);
+
+// F) Decoded image is now in config.output (and config.output.u.RGBA).
+// It can be saved, displayed or otherwise processed.
+
+// G) Reclaim memory allocated in config's object. It's safe to call
+// this function even if the memory is external and wasn't allocated
+// by WebPDecode().
+WebPFreeDecBuffer(&config.output);
+```
+
+## Webp Mux
+
+WebPMux is a set of two libraries 'Mux' and 'Demux' for creation, extraction and
+manipulation of an extended format WebP file, which can have features like color
+profile, metadata and animation. Reference command-line tools `webpmux` and
+`vwebp` as well as the WebP container specification
+'doc/webp-container-spec.txt' are also provided in this package, see the
+[tools documentation](tools.md).
+
+### Mux API
+
+The Mux API contains methods for adding data to and reading data from WebP
+files. This API currently supports XMP/EXIF metadata, ICC profile and animation.
+Other features may be added in subsequent releases.
+
+Example#1 (pseudo code): Creating a WebPMux object with image data, color
+profile and XMP metadata.
+
+```c
+int copy_data = 0;
+WebPMux* mux = WebPMuxNew();
+// ... (Prepare image data).
+WebPMuxSetImage(mux, &image, copy_data);
+// ... (Prepare ICC profile data).
+WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
+// ... (Prepare XMP metadata).
+WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
+// Get data from mux in WebP RIFF format.
+WebPMuxAssemble(mux, &output_data);
+WebPMuxDelete(mux);
+// ... (Consume output_data; e.g. write output_data.bytes to file).
+WebPDataClear(&output_data);
+```
+
+Example#2 (pseudo code): Get image and color profile data from a WebP file.
+
+```c
+int copy_data = 0;
+// ... (Read data from file).
+WebPMux* mux = WebPMuxCreate(&data, copy_data);
+WebPMuxGetFrame(mux, 1, &image);
+// ... (Consume image; e.g. call WebPDecode() to decode the data).
+WebPMuxGetChunk(mux, "ICCP", &icc_profile);
+// ... (Consume icc_profile).
+WebPMuxDelete(mux);
+free(data);
+```
+
+For a detailed Mux API reference, please refer to the header file
+(src/webp/mux.h).
+
+### Demux API
+
+The Demux API enables extraction of images and extended format data from WebP
+files. This API currently supports reading of XMP/EXIF metadata, ICC profile and
+animated images. Other features may be added in subsequent releases.
+
+Code example: Demuxing WebP data to extract all the frames, ICC profile and
+EXIF/XMP metadata.
+
+```c
+WebPDemuxer* demux = WebPDemux(&webp_data);
+uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
+uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
+// ... (Get information about the features present in the WebP file).
+uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
+
+// ... (Iterate over all frames).
+WebPIterator iter;
+if (WebPDemuxGetFrame(demux, 1, &iter)) {
+  do {
+    // ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
+    // ... and get other frame properties like width, height, offsets etc.
+    // ... see 'struct WebPIterator' below for more info).
+  } while (WebPDemuxNextFrame(&iter));
+  WebPDemuxReleaseIterator(&iter);
+}
+
+// ... (Extract metadata).
+WebPChunkIterator chunk_iter;
+if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
+// ... (Consume the ICC profile in 'chunk_iter.chunk').
+WebPDemuxReleaseChunkIterator(&chunk_iter);
+if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
+// ... (Consume the EXIF metadata in 'chunk_iter.chunk').
+WebPDemuxReleaseChunkIterator(&chunk_iter);
+if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
+// ... (Consume the XMP metadata in 'chunk_iter.chunk').
+WebPDemuxReleaseChunkIterator(&chunk_iter);
+WebPDemuxDelete(demux);
+```
+
+For a detailed Demux API reference, please refer to the header file
+(src/webp/demux.h).
+
+## AnimEncoder API
+
+The AnimEncoder API can be used to create animated WebP images.
+
+Code example:
+
+```c
+WebPAnimEncoderOptions enc_options;
+WebPAnimEncoderOptionsInit(&enc_options);
+// ... (Tune 'enc_options' as needed).
+WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
+while(<there are more frames>) {
+  WebPConfig config;
+  WebPConfigInit(&config);
+  // ... (Tune 'config' as needed).
+  WebPAnimEncoderAdd(enc, frame, duration, &config);
+}
+WebPAnimEncoderAssemble(enc, webp_data);
+WebPAnimEncoderDelete(enc);
+// ... (Write the 'webp_data' to a file, or re-mux it further).
+```
+
+For a detailed AnimEncoder API reference, please refer to the header file
+(src/webp/mux.h).
+
+## AnimDecoder API
+
+This AnimDecoder API allows decoding (possibly) animated WebP images.
+
+Code Example:
+
+```c
+WebPAnimDecoderOptions dec_options;
+WebPAnimDecoderOptionsInit(&dec_options);
+// Tune 'dec_options' as needed.
+WebPAnimDecoder* dec = WebPAnimDecoderNew(webp_data, &dec_options);
+WebPAnimInfo anim_info;
+WebPAnimDecoderGetInfo(dec, &anim_info);
+for (uint32_t i = 0; i < anim_info.loop_count; ++i) {
+  while (WebPAnimDecoderHasMoreFrames(dec)) {
+    uint8_t* buf;
+    int timestamp;
+    WebPAnimDecoderGetNext(dec, &buf, &timestamp);
+    // ... (Render 'buf' based on 'timestamp').
+    // ... (Do NOT free 'buf', as it is owned by 'dec').
+  }
+  WebPAnimDecoderReset(dec);
+}
+const WebPDemuxer* demuxer = WebPAnimDecoderGetDemuxer(dec);
+// ... (Do something using 'demuxer'; e.g. get EXIF/XMP/ICC data).
+WebPAnimDecoderDelete(dec);
+```
+
+For a detailed AnimDecoder API reference, please refer to the header file
+(src/webp/demux.h).

doc/building.md

@@ -0,0 +1,213 @@
+# Building
+
+## Windows build
+
+By running:
+
+```batch
+nmake /f Makefile.vc CFG=release-static RTLIBCFG=static OBJDIR=output
+```
+
+the directory `output\release-static\(x64|x86)\bin` will contain the tools
+cwebp.exe and dwebp.exe. The directory `output\release-static\(x64|x86)\lib`
+will contain the libwebp static library. The target architecture (x86/x64) is
+detected by Makefile.vc from the Visual Studio compiler (cl.exe) available in
+the system path.
+
+## Unix build using makefile.unix
+
+On platforms with GNU tools installed (gcc and make), running
+
+```shell
+make -f makefile.unix
+```
+
+will build the binaries examples/cwebp and examples/dwebp, along with the static
+library src/libwebp.a. No system-wide installation is supplied, as this is a
+simple alternative to the full installation system based on the autoconf tools
+(see below). Please refer to makefile.unix for additional details and
+customizations.
+
+## Using autoconf tools
+
+Prerequisites: a compiler (e.g., gcc), make, autoconf, automake, libtool.
+
+On a Debian-like system the following should install everything you need for a
+minimal build:
+
+```shell
+$ sudo apt-get install gcc make autoconf automake libtool
+```
+
+When building from git sources, you will need to run autogen.sh to generate the
+configure script.
+
+```shell
+./configure
+make
+make install
+```
+
+should be all you need to have the following files
+
+```
+/usr/local/include/webp/decode.h
+/usr/local/include/webp/encode.h
+/usr/local/include/webp/types.h
+/usr/local/lib/libwebp.*
+/usr/local/bin/cwebp
+/usr/local/bin/dwebp
+```
+
+installed.
+
+Note: A decode-only library, libwebpdecoder, is available using the
+`--enable-libwebpdecoder` flag. The encode library is built separately and can
+be installed independently using a minor modification in the corresponding
+Makefile.am configure files (see comments there). See `./configure --help` for
+more options.
+
+## Building for MIPS Linux
+
+MIPS Linux toolchain stable available releases can be found at:
+https://community.imgtec.com/developers/mips/tools/codescape-mips-sdk/available-releases/
+
+```shell
+# Add toolchain to PATH
+export PATH=$PATH:/path/to/toolchain/bin
+
+# 32-bit build for mips32r5 (p5600)
+HOST=mips-mti-linux-gnu
+MIPS_CFLAGS="-O3 -mips32r5 -mabi=32 -mtune=p5600 -mmsa -mfp64 \
+  -msched-weight -mload-store-pairs -fPIE"
+MIPS_LDFLAGS="-mips32r5 -mabi=32 -mmsa -mfp64 -pie"
+
+# 64-bit build for mips64r6 (i6400)
+HOST=mips-img-linux-gnu
+MIPS_CFLAGS="-O3 -mips64r6 -mabi=64 -mtune=i6400 -mmsa -mfp64 \
+  -msched-weight -mload-store-pairs -fPIE"
+MIPS_LDFLAGS="-mips64r6 -mabi=64 -mmsa -mfp64 -pie"
+
+./configure --host=${HOST} --build=`config.guess` \
+  CC="${HOST}-gcc -EL" \
+  CFLAGS="$MIPS_CFLAGS" \
+  LDFLAGS="$MIPS_LDFLAGS"
+make
+make install
+```
+
+## CMake
+
+With CMake, you can compile libwebp, cwebp, dwebp, gif2webp, img2webp, webpinfo
+and the JS bindings.
+
+Prerequisites: a compiler (e.g., gcc with autotools) and CMake.
+
+On a Debian-like system the following should install everything you need for a
+minimal build:
+
+```shell
+$ sudo apt-get install build-essential cmake
+```
+
+When building from git sources, you will need to run cmake to generate the
+makefiles.
+
+```shell
+mkdir build && cd build && cmake ../
+make
+make install
+```
+
+If you also want any of the executables, you will need to enable them through
+CMake, e.g.:
+
+```shell
+cmake -DWEBP_BUILD_CWEBP=ON -DWEBP_BUILD_DWEBP=ON ../
+```
+
+or through your favorite interface (like ccmake or cmake-qt-gui).
+
+Use option `-DWEBP_UNICODE=ON` for Unicode support on Windows (with chcp 65001).
+
+Finally, once installed, you can also use WebP in your CMake project by doing:
+
+```cmake
+find_package(WebP)
+```
+
+which will define the CMake variables WebP_INCLUDE_DIRS and WebP_LIBRARIES.
+
+## Gradle
+
+The support for Gradle is minimal: it only helps you compile libwebp, cwebp and
+dwebp and webpmux_example.
+
+Prerequisites: a compiler (e.g., gcc with autotools) and gradle.
+
+On a Debian-like system the following should install everything you need for a
+minimal build:
+
+```shell
+$ sudo apt-get install build-essential gradle
+```
+
+When building from git sources, you will need to run the Gradle wrapper with the
+appropriate target, e.g. :
+
+```shell
+./gradlew buildAllExecutables
+```
+
+## SWIG bindings
+
+To generate language bindings from swig/libwebp.swig at least swig-1.3
+(http://www.swig.org) is required.
+
+Currently the following functions are mapped:
+
+Decode:
+
+```
+WebPGetDecoderVersion
+WebPGetInfo
+WebPDecodeRGBA
+WebPDecodeARGB
+WebPDecodeBGRA
+WebPDecodeBGR
+WebPDecodeRGB
+```
+
+Encode:
+
+```
+WebPGetEncoderVersion
+WebPEncodeRGBA
+WebPEncodeBGRA
+WebPEncodeRGB
+WebPEncodeBGR
+WebPEncodeLosslessRGBA
+WebPEncodeLosslessBGRA
+WebPEncodeLosslessRGB
+WebPEncodeLosslessBGR
+```
+
+See also the [swig documentation](../swig/README.md) for more detailed build
+instructions and usage examples.
+
+### Java bindings
+
+To build the swig-generated JNI wrapper code at least JDK-1.5 (or equivalent) is
+necessary for enum support. The output is intended to be a shared object / DLL
+that can be loaded via `System.loadLibrary("webp_jni")`.
+
+### Python bindings
+
+To build the swig-generated Python extension code at least Python 2.6 is
+required. Python < 2.6 may build with some minor changes to libwebp.swig or the
+generated code, but is untested.
+
+## Javascript decoder
+
+Libwebp can be compiled into a JavaScript decoder using Emscripten and CMake.
+See the [corresponding documentation](../README.md)

doc/specs_generation.md

@@ -0,0 +1,26 @@
+# Generate libwebp Container Spec Docs from Text Source
+
+HTML generation requires [kramdown](https://kramdown.gettalong.org/), easily
+installed as a [rubygem](https://rubygems.org/). Rubygems installation should
+satisfy dependencies automatically.
+
+HTML generation can then be done from the project root:
+
+```shell
+$ kramdown doc/webp-container-spec.txt --template doc/template.html > \
+  doc/output/webp-container-spec.html
+```
+
+kramdown can optionally syntax highlight code blocks, using
+[CodeRay](https://github.com/rubychan/coderay), a dependency of kramdown that
+rubygems will install automatically. The following will apply inline CSS
+styling; an external stylesheet is not needed.
+
+```shell
+$ kramdown doc/webp-lossless-bitstream-spec.txt --template \
+  doc/template.html --coderay-css style --coderay-line-numbers ' ' \
+  --coderay-default-lang c > \
+  doc/output/webp-lossless-bitstream-spec.html
+```
+
+Optimally, use kramdown 0.13.7 or newer if syntax highlighting desired.

doc/tools.md

@@ -0,0 +1,512 @@
+# WebP tools
+
+## Encoding tool
+
+The examples/ directory contains tools for encoding (cwebp) and decoding (dwebp)
+images.
+
+The easiest use should look like:
+
+```shell
+cwebp input.png -q 80 -o output.webp
+```
+
+which will convert the input file to a WebP file using a quality factor of 80 on
+a 0->100 scale (0 being the lowest quality, 100 being the best. Default value is
+75).
+
+You might want to try the `-lossless` flag too, which will compress the source
+(in RGBA format) without any loss. The `-q` quality parameter will in this case
+control the amount of processing time spent trying to make the output file as
+small as possible.
+
+A longer list of options is available using the `-longhelp` command line flag:
+
+```shell
+> cwebp -longhelp
+Usage:
+ cwebp [-preset <...>] [options] in_file [-o out_file]
+```
+
+If input size (-s) for an image is not specified, it is assumed to be a PNG,
+JPEG, TIFF or WebP file. Note: Animated PNG and WebP files are not supported.
+
+Options:
+
+```
+-h / -help ............. short help
+-H / -longhelp ......... long help
+-q <float> ............. quality factor (0:small..100:big), default=75
+-alpha_q <int> ......... transparency-compression quality (0..100),
+                         default=100
+-preset <string> ....... preset setting, one of:
+                          default, photo, picture,
+                          drawing, icon, text
+   -preset must come first, as it overwrites other parameters
+-z <int> ............... activates lossless preset with given
+                         level in [0:fast, ..., 9:slowest]
+
+-m <int> ............... compression method (0=fast, 6=slowest), default=4
+-segments <int> ........ number of segments to use (1..4), default=4
+-size <int> ............ target size (in bytes)
+-psnr <float> .......... target PSNR (in dB. typically: 42)
+
+-s <int> <int> ......... input size (width x height) for YUV
+-sns <int> ............. spatial noise shaping (0:off, 100:max), default=50
+-f <int> ............... filter strength (0=off..100), default=60
+-sharpness <int> ....... filter sharpness (0:most .. 7:least sharp), default=0
+-strong ................ use strong filter instead of simple (default)
+-nostrong .............. use simple filter instead of strong
+-sharp_yuv ............. use sharper (and slower) RGB->YUV conversion
+-partition_limit <int> . limit quality to fit the 512k limit on
+                         the first partition (0=no degradation ... 100=full)
+-pass <int> ............ analysis pass number (1..10)
+-qrange <min> <max> .... specifies the permissible quality range
+                         (default: 0 100)
+-crop <x> <y> <w> <h> .. crop picture with the given rectangle
+-resize <w> <h> ........ resize picture (*after* any cropping)
+-mt .................... use multi-threading if available
+-low_memory ............ reduce memory usage (slower encoding)
+-map <int> ............. print map of extra info
+-print_psnr ............ prints averaged PSNR distortion
+-print_ssim ............ prints averaged SSIM distortion
+-print_lsim ............ prints local-similarity distortion
+-d <file.pgm> .......... dump the compressed output (PGM file)
+-alpha_method <int> .... transparency-compression method (0..1), default=1
+-alpha_filter <string> . predictive filtering for alpha plane,
+                         one of: none, fast (default) or best
+-exact ................. preserve RGB values in transparent area, default=off
+-blend_alpha <hex> ..... blend colors against background color
+                         expressed as RGB values written in
+                         hexadecimal, e.g. 0xc0e0d0 for red=0xc0
+                         green=0xe0 and blue=0xd0
+-noalpha ............... discard any transparency information
+-lossless .............. encode image losslessly, default=off
+-near_lossless <int> ... use near-lossless image
+                         preprocessing (0..100=off), default=100
+-hint <string> ......... specify image characteristics hint,
+                         one of: photo, picture or graph
+
+-metadata <string> ..... comma separated list of metadata to
+                         copy from the input to the output if present.
+                         Valid values: all, none (default), exif, icc, xmp
+
+-short ................. condense printed message
+-quiet ................. don't print anything
+-version ............... print version number and exit
+-noasm ................. disable all assembly optimizations
+-v ..................... verbose, e.g. print encoding/decoding times
+-progress .............. report encoding progress
+```
+
+Experimental Options:
+
+```
+-jpeg_like ............. roughly match expected JPEG size
+-af .................... auto-adjust filter strength
+-pre <int> ............. pre-processing filter
+```
+
+The main options you might want to try in order to further tune the visual
+quality are:
+
+-preset -sns -f -m
+
+Namely:
+
+*   `preset` will set up a default encoding configuration targeting a particular
+    type of input. It should appear first in the list of options, so that
+    subsequent options can take effect on top of this preset. Default value is
+    'default'.
+*   `sns` will progressively turn on (when going from 0 to 100) some additional
+    visual optimizations (like: segmentation map re-enforcement). This option
+    will balance the bit allocation differently. It tries to take bits from the
+    "easy" parts of the picture and use them in the "difficult" ones instead.
+    Usually, raising the sns value (at fixed -q value) leads to larger files,
+    but with better quality. Typical value is around '75'.
+*   `f` option directly links to the filtering strength used by the codec's
+    in-loop processing. The higher the value, the smoother the highly-compressed
+    area will look. This is particularly useful when aiming at very small files.
+    Typical values are around 20-30. Note that using the option
+    -strong/-nostrong will change the type of filtering. Use "-f 0" to turn
+    filtering off.
+*   `m` controls the trade-off between encoding speed and quality. Default is 4.
+    You can try -m 5 or -m 6 to explore more (time-consuming) encoding
+    possibilities. A lower value will result in faster encoding at the expense
+    of quality.
+
+## Decoding tool
+
+There is a decoding sample in examples/dwebp.c which will take a .webp file and
+decode it to a PNG image file (amongst other formats). This is simply to
+demonstrate the use of the API. You can verify the file test.webp decodes to
+exactly the same as test_ref.ppm by using:
+
+```shell
+cd examples
+./dwebp test.webp -ppm -o test.ppm
+diff test.ppm test_ref.ppm
+```
+
+The full list of options is available using -h:
+
+```shell
+> dwebp -h
+Usage: dwebp in_file [options] [-o out_file]
+```
+
+Decodes the WebP image file to PNG format [Default]. Note: Animated WebP files
+are not supported.
+
+Use following options to convert into alternate image formats:
+
+```
+-pam ......... save the raw RGBA samples as a color PAM
+-ppm ......... save the raw RGB samples as a color PPM
+-bmp ......... save as uncompressed BMP format
+-tiff ........ save as uncompressed TIFF format
+-pgm ......... save the raw YUV samples as a grayscale PGM
+               file with IMC4 layout
+-yuv ......... save the raw YUV samples in flat layout
+```
+
+Other options are:
+
+```
+-version ..... print version number and exit
+-nofancy ..... don't use the fancy YUV420 upscaler
+-nofilter .... disable in-loop filtering
+-nodither .... disable dithering
+-dither <d> .. dithering strength (in 0..100)
+-alpha_dither  use alpha-plane dithering if needed
+-mt .......... use multi-threading
+-crop <x> <y> <w> <h> ... crop output with the given rectangle
+-resize <w> <h> ......... resize output (*after* any cropping)
+-flip ........ flip the output vertically
+-alpha ....... only save the alpha plane
+-incremental . use incremental decoding (useful for tests)
+-h ........... this help message
+-v ........... verbose (e.g. print encoding/decoding times)
+-quiet ....... quiet mode, don't print anything
+-noasm ....... disable all assembly optimizations
+```
+
+## WebP file analysis tool
+
+`webpinfo` can be used to print out the chunk level structure and bitstream
+header information of WebP files. It can also check if the files are of valid
+WebP format.
+
+Usage:
+
+```shell
+webpinfo [options] in_files
+```
+
+Note: there could be multiple input files; options must come before input files.
+
+Options:
+
+```
+-version ........... Print version number and exit.
+-quiet ............. Do not show chunk parsing information.
+-diag .............. Show parsing error diagnosis.
+-summary ........... Show chunk stats summary.
+-bitstream_info .... Parse bitstream header.
+```
+
+## Visualization tool
+
+There's a little self-serve visualization tool called 'vwebp' under the
+examples/ directory. It uses OpenGL to open a simple drawing window and show a
+decoded WebP file. It's not yet integrated in the automake build system, but you
+can try to manually compile it using the recommendations below.
+
+Usage:
+
+```shell
+vwebp in_file [options]
+```
+
+Decodes the WebP image file and visualize it using OpenGL
+
+Options are:
+
+```
+-version ..... print version number and exit
+-noicc ....... don't use the icc profile if present
+-nofancy ..... don't use the fancy YUV420 upscaler
+-nofilter .... disable in-loop filtering
+-dither <int>  dithering strength (0..100), default=50
+-noalphadither disable alpha plane dithering
+-usebgcolor .. display background color
+-mt .......... use multi-threading
+-info ........ print info
+-h ........... this help message
+```
+
+Keyboard shortcuts:
+
+```
+'c' ................ toggle use of color profile
+'b' ................ toggle background color display
+'i' ................ overlay file information
+'d' ................ disable blending & disposal (debug)
+'q' / 'Q' / ESC .... quit
+```
+
+### Building
+
+Prerequisites:
+
+1.  OpenGL & OpenGL Utility Toolkit (GLUT)
+
+    Linux: `sudo apt-get install freeglut3-dev mesa-common-dev`
+
+    Mac + Xcode: These libraries should be available in the OpenGL / GLUT
+    frameworks.
+
+    Windows: http://freeglut.sourceforge.net/index.php#download
+
+2.  (Optional) qcms (Quick Color Management System)
+
+    1.  Download qcms from Mozilla / Chromium:
+        https://hg.mozilla.org/mozilla-central/file/0e7639e3bdfb/gfx/qcms
+        https://source.chromium.org/chromium/chromium/src/+/main:third_party/qcms/;drc=d4a2f8e1ed461d8fc05ed88d1ae2dc94c9773825
+    2.  Build and archive the source files as libqcms.a / qcms.lib
+    3.  Update makefile.unix / Makefile.vc
+        1.  Define WEBP_HAVE_QCMS
+        2.  Update include / library paths to reference the qcms directory.
+
+Build using makefile.unix / Makefile.vc:
+
+```shell
+$ make -f makefile.unix examples/vwebp
+> nmake /f Makefile.vc CFG=release-static \
+    ../obj/x64/release-static/bin/vwebp.exe
+```
+
+## Animation creation tool
+
+The utility `img2webp` can turn a sequence of input images (PNG, JPEG, ...) into
+an animated WebP file. It offers fine control over duration, encoding modes,
+etc.
+
+Usage:
+
+```shell
+img2webp [file_options] [[frame_options] frame_file]...
+```
+
+File-level options (only used at the start of compression):
+
+```
+-min_size ............ minimize size
+-loop <int> .......... loop count (default: 0, = infinite loop)
+-kmax <int> .......... maximum number of frame between key-frames
+                        (0=only keyframes)
+-kmin <int> .......... minimum number of frame between key-frames
+                        (0=disable key-frames altogether)
+-mixed ............... use mixed lossy/lossless automatic mode
+-v ................... verbose mode
+-h ................... this help
+-version ............. print version number and exit
+```
+
+Per-frame options (only used for subsequent images input):
+
+```
+-d <int> ............. frame duration in ms (default: 100)
+-lossless  ........... use lossless mode (default)
+-lossy ... ........... use lossy mode
+-q <float> ........... quality
+-m <int> ............. method to use
+```
+
+example: `img2webp -loop 2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp`
+
+Note: if a single file name is passed as the argument, the arguments will be
+tokenized from this file. The file name must not start with the character '-'.
+
+## Animated GIF conversion
+
+Animated GIF files can be converted to WebP files with animation using the
+gif2webp utility available under examples/. The files can then be viewed using
+vwebp.
+
+Usage:
+
+```shell
+gif2webp [options] gif_file -o webp_file
+```
+
+Options:
+
+```
+-h / -help ............. this help
+-lossy ................. encode image using lossy compression
+-mixed ................. for each frame in the image, pick lossy
+                         or lossless compression heuristically
+-q <float> ............. quality factor (0:small..100:big)
+-m <int> ............... compression method (0=fast, 6=slowest)
+-min_size .............. minimize output size (default:off)
+                         lossless compression by default; can be
+                         combined with -q, -m, -lossy or -mixed
+                         options
+-kmin <int> ............ min distance between key frames
+-kmax <int> ............ max distance between key frames
+-f <int> ............... filter strength (0=off..100)
+-metadata <string> ..... comma separated list of metadata to
+                         copy from the input to the output if present
+                         Valid values: all, none, icc, xmp (default)
+-loop_compatibility .... use compatibility mode for Chrome
+                         version prior to M62 (inclusive)
+-mt .................... use multi-threading if available
+
+-version ............... print version number and exit
+-v ..................... verbose
+-quiet ................. don't print anything
+```
+
+### Building
+
+With the libgif development files installed, gif2webp can be built using
+makefile.unix:
+
+```shell
+$ make -f makefile.unix examples/gif2webp
+```
+
+or using autoconf:
+
+```shell
+$ ./configure --enable-everything
+$ make
+```
+
+## Comparison of animated images
+
+Test utility anim_diff under examples/ can be used to compare two animated
+images (each can be GIF or WebP).
+
+Usage:
+
+```shell
+anim_diff <image1> <image2> [options]
+```
+
+Options:
+
+```
+-dump_frames <folder> dump decoded frames in PAM format
+-min_psnr <float> ... minimum per-frame PSNR
+-raw_comparison ..... if this flag is not used, RGB is
+                      premultiplied before comparison
+-max_diff <int> ..... maximum allowed difference per channel
+                      between corresponding pixels in subsequent
+                      frames
+-h .................. this help
+-version ............ print version number and exit
+```
+
+### Building
+
+With the libgif development files installed, anim_diff can be built using
+makefile.unix:
+
+```shell
+$ make -f makefile.unix examples/anim_diff
+```
+
+or using autoconf:
+
+```shell
+$ ./configure --enable-everything
+$ make
+```
+
+## WebP Mux tool
+
+The examples/ directory contains a tool (webpmux) for manipulating WebP files.
+The webpmux tool can be used to create an extended format WebP file and also to
+extract or strip relevant data from such a file.
+
+A list of options is available using the -help command line flag:
+
+```shell
+> webpmux -help
+Usage: webpmux -get GET_OPTIONS INPUT -o OUTPUT
+       webpmux -set SET_OPTIONS INPUT -o OUTPUT
+       webpmux -duration DURATION_OPTIONS [-duration ...]
+               INPUT -o OUTPUT
+       webpmux -strip STRIP_OPTIONS INPUT -o OUTPUT
+       webpmux -frame FRAME_OPTIONS [-frame...] [-loop LOOP_COUNT]
+               [-bgcolor BACKGROUND_COLOR] -o OUTPUT
+       webpmux -info INPUT
+       webpmux [-h|-help]
+       webpmux -version
+       webpmux argument_file_name
+
+GET_OPTIONS:
+ Extract relevant data:
+   icc       get ICC profile
+   exif      get EXIF metadata
+   xmp       get XMP metadata
+   frame n   get nth frame
+
+SET_OPTIONS:
+ Set color profile/metadata/parameters:
+   loop LOOP_COUNT            set the loop count
+   bgcolor BACKGROUND_COLOR   set the animation background color
+   icc  file.icc              set ICC profile
+   exif file.exif             set EXIF metadata
+   xmp  file.xmp              set XMP metadata
+   where:    'file.icc' contains the ICC profile to be set,
+             'file.exif' contains the EXIF metadata to be set
+             'file.xmp' contains the XMP metadata to be set
+
+DURATION_OPTIONS:
+ Set duration of selected frames:
+   duration            set duration for all frames
+   duration,frame      set duration of a particular frame
+   duration,start,end  set duration of frames in the
+                        interval [start,end])
+   where: 'duration' is the duration in milliseconds
+          'start' is the start frame index
+          'end' is the inclusive end frame index
+           The special 'end' value '0' means: last frame.
+
+STRIP_OPTIONS:
+ Strip color profile/metadata:
+   icc       strip ICC profile
+   exif      strip EXIF metadata
+   xmp       strip XMP metadata
+
+FRAME_OPTIONS(i):
+ Create animation:
+   file_i +di[+xi+yi[+mi[bi]]]
+   where:    'file_i' is the i'th animation frame (WebP format),
+             'di' is the pause duration before next frame,
+             'xi','yi' specify the image offset for this frame,
+             'mi' is the dispose method for this frame (0 or 1),
+             'bi' is the blending method for this frame (+b or -b)
+
+LOOP_COUNT:
+ Number of times to repeat the animation.
+ Valid range is 0 to 65535 [Default: 0 (infinite)].
+
+BACKGROUND_COLOR:
+ Background color of the canvas.
+  A,R,G,B
+  where:    'A', 'R', 'G' and 'B' are integers in the range 0 to 255 specifying
+            the Alpha, Red, Green and Blue component values respectively
+            [Default: 255,255,255,255]
+
+INPUT & OUTPUT are in WebP format.
+
+Note: The nature of EXIF, XMP and ICC data is not checked and is assumed to be
+valid.
+
+Note: if a single file name is passed as the argument, the arguments will be
+tokenized from this file. The file name must not start with the character '-'.
+```

doc/webp-container-spec.txt

@@ -2,10 +2,10 @@
 
 Although you may be viewing an alternate representation, this document
 is sourced in Markdown, a light-duty markup scheme, and is optimized for
-the [kramdown](http://kramdown.rubyforge.org/) transformer.
+the [kramdown](https://kramdown.gettalong.org/) transformer.
 
-See the accompanying README. External link targets are referenced at the
-end of this file.
+See the accompanying specs_generation.md. External link targets are referenced
+at the end of this file.
 
 -->
 
@@ -36,7 +36,7 @@ for:
   * **Lossless compression.** An image can be losslessly compressed, using the
     WebP Lossless Format.
 
-  * **Metadata.** An image may have metadata stored in EXIF or XMP formats.
+  * **Metadata.** An image may have metadata stored in Exif or XMP formats.
 
   * **Transparency.** An image may have transparency, i.e., an alpha channel.
 
@@ -46,25 +46,12 @@ for:
   * **Animation.** An image may have multiple frames with pauses between them,
     making it an animation.
 
-  * **Image Fragmentation.** A single bitstream in WebP has an inherent
-    limitation for width or height of 2^14 pixels, and, when using VP8, a 512
-    KiB limit on the size of the first compressed partition. To support larger
-    images, the format supports images that are composed of multiple fragments,
-    each encoded as a separate bitstream. All fragments logically form a single
-    image: they have common metadata, color profile, etc. Image fragmentation
-    may also improve efficiency for larger images, e.g., grass can be encoded
-    differently than sky.
-
 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
 document are to be interpreted as described in [RFC 2119][].
 
-**Note:** Out of the features mentioned above, lossy compression, lossless
-compression, transparency, metadata, color profile and animation are finalized
-and are to be considered stable. On the other hand, image fragmentation is
-experimental as of now, and is open to discussion, feedback and comments.
-The same is indicated using annotation "_status: experimental_" in the relevant
-sections of this document.
+Bit numbering in chunk diagrams starts at `0` for the most significant bit
+('MSB 0') as described in [RFC 1166][].
 
 Terminology & Basics
 ------------------------
@@ -79,7 +66,7 @@ Below are additional terms used throughout this document:
 _Reader/Writer_
 
 : Code that reads WebP files is referred to as a _reader_, while code that
-writes them is referred to as a _writer_.
+  writes them is referred to as a _writer_.
 
 _uint16_
 
@@ -101,11 +88,13 @@ _FourCC_
 _1-based_
 
 : An unsigned integer field storing values offset by `-1`. e.g., Such a field
-would store value _25_ as _24_.
+  would store value _25_ as _24_.
 
-RIFF file format
+
+RIFF File Format
 ----------------
-The WebP file format is based on the RIFF (resource interchange file format)
+
+The WebP file format is based on the RIFF (Resource Interchange File Format)
 document format.
 
 The basic element of a RIFF file is a _chunk_. It consists of:
@@ -144,7 +133,8 @@ _ChunkHeader('ABCD')_
 chunks that apply to any RIFF file format, while FourCCs specific to a file
 format are all lowercase. WebP does not follow this convention.
 
-WebP file header
+
+WebP File Header
 ----------------
 
      0                   1                   2                   3
@@ -164,8 +154,8 @@ WebP file header
 File Size: 32 bits (_uint32_)
 
 : The size of the file in bytes starting at offset 8. The maximum value of
-this field is 2^32 minus 10 bytes and thus the size of the whole file is at
-most 4GiB minus 2 bytes.
+  this field is 2^32 minus 10 bytes and thus the size of the whole file is at
+  most 4GiB minus 2 bytes.
 
 'WEBP': 32 bits
 
@@ -177,7 +167,8 @@ the 'WEBP' FourCC. The file SHOULD NOT contain anything after it. As the size
 of any chunk is even, the size given by the RIFF header is also even. The
 contents of individual chunks will be described in the following sections.
 
-Simple file format (lossy)
+
+Simple File Format (Lossy)
 --------------------------
 
 This layout SHOULD be used if the image requires _lossy_ encoding and does not
@@ -215,7 +206,8 @@ width and height. That is assumed to be the width and height of the canvas.
 The VP8 specification describes how to decode the image into Y'CbCr
 format. To convert to RGB, Rec. 601 SHOULD be used.
 
-Simple file format (lossless)
+
+Simple File Format (Lossless)
 -----------------------------
 
 **Note:** Older readers may not support files using the lossless format.
@@ -253,7 +245,8 @@ The current specification of the VP8L bitstream can be found at
 contains the VP8L image width and height. That is assumed to be the width
 and height of the canvas.
 
-Extended file format
+
+Extended File Format
 --------------------
 
 **Note:** Older readers may not support files using the extended format.
@@ -268,19 +261,21 @@ An extended format file consists of:
 
   * Image data.
 
-  * An optional 'EXIF' chunk with EXIF metadata.
+  * An optional 'EXIF' chunk with Exif metadata.
 
   * An optional 'XMP ' chunk with XMP metadata.
 
-  * An optional list of [unknown chunks](#unknown-chunks). _\[status: experimental\]_
+  * An optional list of [unknown chunks](#unknown-chunks).
 
-For a _still image_, the _image data_ consists of a single frame, whereas for
-an _animated image_, it consists of multiple frames. More details about frames
-can be found in the [Animation](#animation) section.
+For a _still image_, the _image data_ consists of a single frame, which is made
+up of:
 
-Moreover, each frame can be fragmented or non-fragmented, as will be described
-in the [Extended WebP file header](#extended_header) section. More details about
-fragments can be found in the [Fragments](#fragments) section.
+  * An optional [alpha subchunk](#alpha).
+
+  * A [bitstream subchunk](#bitstream-vp8vp8l).
+
+For an _animated image_, the _image data_ consists of multiple frames. More
+details about frames can be found in the [Animation](#animation) section.
 
 All chunks SHOULD be placed in the same order as listed above. If a chunk
 appears in the wrong place, the file is invalid, but readers MAY parse the
@@ -302,7 +297,7 @@ Extended WebP file header:
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                      ChunkHeader('VP8X')                      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |Rsv|I|L|E|X|A|F|                   Reserved                    |
+    |Rsv|I|L|E|X|A|R|                   Reserved                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Canvas Width Minus One               |             ...
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
@@ -320,11 +315,11 @@ ICC profile (I): 1 bit
 Alpha (L): 1 bit
 
 : Set if any of the frames of the image contain transparency information
-("alpha").
+  ("alpha").
 
-EXIF metadata (E): 1 bit
+Exif metadata (E): 1 bit
 
-: Set if the file contains EXIF metadata.
+: Set if the file contains Exif metadata.
 
 XMP metadata (X): 1 bit
 
@@ -333,11 +328,11 @@ XMP metadata (X): 1 bit
 Animation (A): 1 bit
 
 : Set if this is an animated image. Data in 'ANIM' and 'ANMF' chunks should be
-used to control the animation.
+  used to control the animation.
 
-Image Fragmentation (F): 1 bit _\[status: experimental\]_
+Reserved (R): 1 bit
 
-: Set if any of the frames in the image are represented by fragments.
+: SHOULD be `0`.
 
 Reserved: 24 bits
 
@@ -346,12 +341,12 @@ Reserved: 24 bits
 Canvas Width Minus One: 24 bits
 
 : _1-based_ width of the canvas in pixels.
-  The actual canvas width is '1 + Canvas Width Minus One'
+  The actual canvas width is `1 + Canvas Width Minus One`.
 
 Canvas Height Minus One: 24 bits
 
 : _1-based_ height of the canvas in pixels.
-  The actual canvas height is '1 + Canvas Height Minus One'
+  The actual canvas height is `1 + Canvas Height Minus One`.
 
 The product of _Canvas Width_ and _Canvas Height_ MUST be at most `2^32 - 1`.
 
@@ -382,9 +377,9 @@ animation.
 Background Color: 32 bits (_uint32_)
 
 : The default background color of the canvas in \[Blue, Green, Red, Alpha\]
-byte order. This color MAY be used to fill the unused space on the canvas around
-the frames, as well as the transparent pixels of the first frame. Background
-color is also used when disposal method is `1`.
+  byte order. This color MAY be used to fill the unused space on the canvas
+  around the frames, as well as the transparent pixels of the first frame.
+  Background color is also used when disposal method is `1`.
 
 **Note**:
 
@@ -394,6 +389,9 @@ color is also used when disposal method is `1`.
   * Viewer applications SHOULD treat the background color value as a hint, and
     are not required to use it.
 
+  * The canvas is cleared at the start of each loop. The background color MAY be
+    used to achieve this.
+
 Loop Count: 16 bits (_uint16_)
 
 : The number of times to loop the animation. `0` means infinitely.
@@ -402,7 +400,6 @@ This chunk MUST appear if the _Animation_ flag in the VP8X chunk is set.
 If the _Animation_ flag is not set and this chunk is present, it
 SHOULD be ignored.
 
-
 ANMF chunk:
 
 For animated images, this chunk contains information about a _single_ frame.
@@ -426,27 +423,28 @@ If the _Animation flag_ is not set, then this chunk SHOULD NOT be present.
 
 Frame X: 24 bits (_uint24_)
 
-: The X coordinate of the upper left corner of the frame is `Frame X * 2`
+: The X coordinate of the upper left corner of the frame is `Frame X * 2`.
 
 Frame Y: 24 bits (_uint24_)
 
-: The Y coordinate of the upper left corner of the frame is `Frame Y * 2`
+: The Y coordinate of the upper left corner of the frame is `Frame Y * 2`.
 
 Frame Width Minus One: 24 bits (_uint24_)
 
 : The _1-based_ width of the frame.
-  The frame width is `1 + Frame Width Minus One`
+  The frame width is `1 + Frame Width Minus One`.
 
 Frame Height Minus One: 24 bits (_uint24_)
 
 : The _1-based_ height of the frame.
-  The frame height is `1 + Frame Height Minus One`
+  The frame height is `1 + Frame Height Minus One`.
 
 Frame Duration: 24 bits (_uint24_)
 
 : The time to wait before displaying the next frame, in 1 millisecond units.
-In particular, frame duration of 0 is useful when one wants to update multiple
-areas of the canvas at once during the animation.
+  Note the interpretation of frame duration of 0 (and often <= 10) is
+  implementation defined. Many tools and browsers assign a minimum duration
+  similar to GIF.
 
 Reserved: 6 bits
 
@@ -454,28 +452,28 @@ Reserved: 6 bits
 
 Blending method (B): 1 bit
 
-: Indicates how transparent pixels of _the current frame_ are to be blended with
-corresponding pixels of the previous canvas:
+: Indicates how transparent pixels of _the current frame_ are to be blended
+  with corresponding pixels of the previous canvas:
 
-  * `0`: Use alpha blending. After disposing of the previous frame, render the
-    current frame on the canvas using [alpha-blending](#alpha-blending). If the
-    current frame does not have an alpha channel, assume alpha value of 255,
-    effectively replacing the rectangle.
+    * `0`: Use alpha blending. After disposing of the previous frame, render the
+      current frame on the canvas using [alpha-blending](#alpha-blending). If
+      the current frame does not have an alpha channel, assume alpha value of
+      255, effectively replacing the rectangle.
 
-  * `1`: Do not blend. After disposing of the previous frame, render the
-    current frame on the canvas by overwriting the rectangle covered by the
-    current frame.
+    * `1`: Do not blend. After disposing of the previous frame, render the
+      current frame on the canvas by overwriting the rectangle covered by the
+      current frame.
 
 Disposal method (D): 1 bit
 
-: Indicates how _the current frame_ is to be treated after it has been displayed
-(before rendering the next frame) on the canvas:
+: Indicates how _the current frame_ is to be treated after it has been
+  displayed (before rendering the next frame) on the canvas:
 
-  * `0`: Do not dispose. Leave the canvas as is.
+    * `0`: Do not dispose. Leave the canvas as is.
 
-  * `1`: Dispose to background color. Fill the _rectangle_ on the canvas covered
-    by the _current frame_ with background color specified in the
-    [ANIM chunk](#anim_chunk).
+    * `1`: Dispose to background color. Fill the _rectangle_ on the canvas
+      covered by the _current frame_ with background color specified in the
+      [ANIM chunk](#anim_chunk).
 
 **Notes**:
 
@@ -506,9 +504,7 @@ Disposal method (D): 1 bit
 
 Frame Data: _Chunk Size_ - `16` bytes
 
-: For a fragmented frame, it consists of multiple [fragment chunks](#fragments).
-
-: For a non-fragmented frame, it consists of:
+: Consists of:
 
   * An optional [alpha subchunk](#alpha) for the frame.
 
@@ -519,49 +515,6 @@ Frame Data: _Chunk Size_ - `16` bytes
 **Note**: The 'ANMF' payload, _Frame Data_ above, consists of individual
 _padded_ chunks as described by the [RIFF file format](#riff-file-format).
 
-#### Fragments _\[status: experimental\]_
-
-For images that are represented by fragments, this chunk contains data for
-a single fragment. If the _Image Fragmentation Flag_ is not set, then this chunk
-SHOULD NOT be present.
-
-     0                   1                   2                   3
-     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                      ChunkHeader('FRGM')                      |
-    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                  Fragment X                   |             ...
-    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    ...       Fragment Y            |         Fragment Data         |
-    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
-Fragment X: 24 bits (_uint24_)
-
-: The X coordinate of the upper left corner of the fragment is `Fragment X * 2`
-
-Fragment Y: 24 bits (_uint24_)
-
-: The Y coordinate of the upper left corner of the fragment is `Fragment Y * 2`
-
-Fragment Data: _Chunk Size_ - `6` bytes
-
-: It contains:
-
-  * An optional [alpha subchunk](#alpha) for the fragment.
-  * The [bitstream subchunk](#bitstream-vp8vp8l) for the fragment.
-  * An optional list of [unknown chunks](#unknown-chunks).
-
-Note: The width and height of the fragment is obtained from the bitstream
-subchunk.
-
-The fragments of a frame SHOULD have the following properties:
-
-  * They collectively cover the whole frame.
-
-  * No pair of fragments have any overlapping region on the frame.
-
-  * No portion of any fragment should be located outside of the canvas.
-
 #### Alpha
 
      0                   1                   2                   3
@@ -579,20 +532,20 @@ Reserved (Rsv): 2 bits
 Pre-processing (P): 2 bits
 
 : These INFORMATIVE bits are used to signal the pre-processing that has
-been performed during compression. The decoder can use this information to
-e.g. dither the values or smooth the gradients prior to display.
+  been performed during compression. The decoder can use this information to
+  e.g. dither the values or smooth the gradients prior to display.
 
-  * `0`: no pre-processing
-  * `1`: level reduction
+    * `0`: no pre-processing
+    * `1`: level reduction
 
 Filtering method (F): 2 bits
 
 : The filtering method used:
 
-  * `0`: None.
-  * `1`: Horizontal filter.
-  * `2`: Vertical filter.
-  * `3`: Gradient filter.
+    * `0`: None.
+    * `1`: Horizontal filter.
+    * `2`: Vertical filter.
+    * `3`: Gradient filter.
 
 For each pixel, filtering is performed using the following calculations.
 Assume the alpha values surrounding the current `X` position are labeled as:
@@ -636,15 +589,15 @@ Compression method (C): 2 bits
 
 : The compression method used:
 
-  * `0`: No compression.
-  * `1`: Compressed using the WebP lossless format.
+    * `0`: No compression.
+    * `1`: Compressed using the WebP lossless format.
 
 Alpha bitstream: _Chunk Size_ - `1` bytes
 
 : Encoded alpha bitstream.
 
-This optional chunk contains encoded alpha data for this frame/fragment. A
-frame/fragment containing a 'VP8L' chunk SHOULD NOT contain this chunk.
+This optional chunk contains encoded alpha data for this frame. A frame
+containing a 'VP8L' chunk SHOULD NOT contain this chunk.
 
 **Rationale**: The transparency information is already part of the 'VP8L'
 chunk.
@@ -675,15 +628,15 @@ compression method is '0') or compressed using the lossless format
 
 #### Bitstream (VP8/VP8L)
 
-This chunk contains compressed bitstream data for a single frame/fragment.
+This chunk contains compressed bitstream data for a single frame.
 
 A bitstream chunk may be either (i) a VP8 chunk, using "VP8 " (note the
 significant fourth-character space) as its tag _or_ (ii) a VP8L chunk, using
 "VP8L" as its tag.
 
 The formats of VP8 and VP8L chunks are as described in sections
-[Simple file format (lossy)](#simple-file-format-lossy)
-and [Simple file format (lossless)](#simple-file-format-lossless) respectively.
+[Simple File Format (Lossy)](#simple-file-format-lossy)
+and [Simple File Format (Lossless)](#simple-file-format-lossless) respectively.
 
 #### Color profile
 
@@ -724,13 +677,12 @@ EXIF chunk:
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                      ChunkHeader('EXIF')                      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                        EXIF Metadata                          |
+    |                        Exif Metadata                          |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
-EXIF Metadata: _Chunk Size_ bytes
-
-: image metadata in EXIF format.
+Exif Metadata: _Chunk Size_ bytes
 
+: image metadata in Exif format.
 
 XMP chunk:
 
@@ -749,7 +701,7 @@ XMP Metadata: _Chunk Size_ bytes
 Additional guidance about handling metadata can be found in the
 Metadata Working Group's [Guidelines for Handling Metadata][metadata].
 
-#### Unknown Chunks _\[status: experimental\]_
+#### Unknown Chunks
 
 A RIFF chunk (described in [this](#terminology-amp-basics) section) whose _chunk
 tag_ is different from any of the chunks described in this document, is
@@ -762,47 +714,17 @@ A file MAY contain unknown chunks:
 
   * At the end of the file as described in [Extended WebP file
     header](#extended_header) section.
-  * At the end of FRGM and ANMF chunks as described in [Fragments](#fragments)
-    and [Animation](#animation) sections.
+  * At the end of ANMF chunks as described in the
+    [Animation](#animation) section.
 
 Readers SHOULD ignore these chunks. Writers SHOULD preserve them in their
 original order (unless they specifically intend to modify these chunks).
 
-### Assembling the Canvas from fragments/frames
+### Assembling the Canvas from frames
 
-Here we provide an overview of how a reader should assemble a canvas in case
-of a fragmented-image and in case of an animated image. The notation
-_VP8X.field_ means the field in the 'VP8X' chunk with the same description.
-
-Displaying a _fragmented image_ canvas MUST be equivalent to the following
-pseudocode: _\[status: experimental\]_
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-assert VP8X.flags.hasFragments
-canvas ← new black image of size VP8X.canvasWidth x VP8X.canvasHeight.
-frgm_params ← nil
-for chunk in image_data:
-    assert chunk.tag is "FRGM"
-    frgm_params.fragmentX = Fragment X
-    frgm_params.fragmentY = Fragment Y
-    for subchunk in 'Fragment Data':
-        if subchunk.tag == "ALPH":
-            assert alpha subchunks not found in 'Fragment Data' earlier
-            frgm_params.alpha = alpha_data
-        else if subchunk.tag == "VP8 " OR subchunk.tag == "VP8L":
-            assert bitstream subchunks not found in 'Fragment Data' earlier
-            frgm_params.bitstream = bitstream_data
-    frgm_params.fragmentWidth = Width extracted from bitstream subchunk
-    frgm_params.fragmentHeight = Height extracted from bitstream subchunk
-    assert VP8X.canvasWidth >=
-        frgm_params.fragmentX + frgm_params.fragmentWidth
-    assert VP8X.canvasHeight >=
-        frgm_params.fragmentY + frgm_params.fragmentHeight
-    assert fragment has the properties mentioned in "Image Fragments" section.
-    render fragment with frame_params.alpha and frame_params.bitstream on canvas
-    with top-left corner in (frgm_params.fragmentX, frgm_params.fragmentY).
-canvas contains the decoded canvas.
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Here we provide an overview of how a reader should assemble a canvas in the
+case of an animated image. The notation _VP8X.field_ means the field in the
+'VP8X' chunk with the same description.
 
 Displaying an _animated image_ canvas MUST be equivalent to the following
 pseudocode:
@@ -810,28 +732,25 @@ pseudocode:
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 assert VP8X.flags.hasAnimation
 canvas ← new image of size VP8X.canvasWidth x VP8X.canvasHeight with
-background color ANIM.background_color.
+         background color ANIM.background_color.
 loop_count ← ANIM.loopCount
 dispose_method ← ANIM.disposeMethod
 if loop_count == 0:
     loop_count = ∞
 frame_params ← nil
-for loop = 0, ..., loop_count - 1
-    assert next chunk in image_data is ANMF
-    frame_params.frameX = Frame X
-    frame_params.frameY = Frame Y
-    frame_params.frameWidth = Frame Width Minus One + 1
-    frame_params.frameHeight = Frame Height Minus One + 1
-    frame_params.frameDuration = Frame Duration
-    assert VP8X.canvasWidth >= frame_params.frameX + frame_params.frameWidth
-    assert VP8X.canvasHeight >= frame_params.frameY + frame_params.frameHeight
-    if VP8X.flags.hasFragments and first subchunk in 'Frame Data' is FRGM
-        // Fragmented frame.
-        frame_params.{bitstream,alpha} = canvas decoded from subchunks in
-                                         'Frame Data' as per the pseudocode for
-                                         _fragmented image_ above.
-    else
-        // Non-fragmented frame.
+assert next chunk in image_data is ANMF
+for loop = 0..loop_count - 1
+    clear canvas to ANIM.background_color or application defined color
+    until eof or non-ANMF chunk
+        frame_params.frameX = Frame X
+        frame_params.frameY = Frame Y
+        frame_params.frameWidth = Frame Width Minus One + 1
+        frame_params.frameHeight = Frame Height Minus One + 1
+        frame_params.frameDuration = Frame Duration
+        frame_right = frame_params.frameX + frame_params.frameWidth
+        frame_bottom = frame_params.frameY + frame_params.frameHeight
+        assert VP8X.canvasWidth >= frame_right
+        assert VP8X.canvasHeight >= frame_bottom
         for subchunk in 'Frame Data':
             if subchunk.tag == "ALPH":
                 assert alpha subchunks not found in 'Frame Data' earlier
@@ -839,14 +758,15 @@ for loop = 0, ..., loop_count - 1
             else if subchunk.tag == "VP8 " OR subchunk.tag == "VP8L":
                 assert bitstream subchunks not found in 'Frame Data' earlier
                 frame_params.bitstream = bitstream_data
-    render frame with frame_params.alpha and frame_params.bitstream on canvas
-    with top-left corner in (frame_params.frameX, frame_params.frameY), using
-    dispose method dispose_method.
-    Show the contents of the image for frame_params.frameDuration * 1ms.
-canvas contains the decoded canvas.
+        render frame with frame_params.alpha and frame_params.bitstream on
+            canvas with top-left corner at (frame_params.frameX,
+            frame_params.frameY), using dispose method dispose_method.
+        canvas contains the decoded image.
+        Show the contents of the canvas for frame_params.frameDuration * 1ms.
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Example file layouts
+
+Example File Layouts
 --------------------
 
 A lossy encoded image with alpha may look as follows:
@@ -878,18 +798,7 @@ RIFF/WEBP
 +- XMP  (metadata)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-A fragmented image may look as follows:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-RIFF/WEBP
-+- VP8X (descriptions of features used)
-+- FRGM (fragment1 parameters + data)
-+- FRGM (fragment2 parameters + data)
-+- FRGM (fragment3 parameters + data)
-+- FRGM (fragment4 parameters + data)
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-An animated image with EXIF metadata may look as follows:
+An animated image with Exif metadata may look as follows:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 RIFF/WEBP
@@ -902,8 +811,9 @@ RIFF/WEBP
 +- EXIF (metadata)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-[vp8spec]:  http://tools.ietf.org/html/rfc6386
-[webpllspec]: https://gerrit.chromium.org/gerrit/gitweb?p=webm/libwebp.git;a=blob;f=doc/webp-lossless-bitstream-spec.txt;hb=master
-[iccspec]: http://www.color.org/icc_specs2.xalter
-[metadata]: http://www.metadataworkinggroup.org/pdf/mwg_guidance.pdf
-[rfc 2119]: http://tools.ietf.org/html/rfc2119
+[vp8spec]:  https://datatracker.ietf.org/doc/html/rfc6386
+[webpllspec]: https://chromium.googlesource.com/webm/libwebp/+/HEAD/doc/webp-lossless-bitstream-spec.txt
+[iccspec]: https://www.color.org/icc_specs2.xalter
+[metadata]: https://web.archive.org/web/20180919181934/http://www.metadataworkinggroup.org/pdf/mwg_guidance.pdf
+[rfc 1166]: https://datatracker.ietf.org/doc/html/rfc1166
+[rfc 2119]: https://datatracker.ietf.org/doc/html/rfc2119

doc/webp-lossless-bitstream-spec.txt

@@ -2,10 +2,10 @@
 
 Although you may be viewing an alternate representation, this document
 is sourced in Markdown, a light-duty markup scheme, and is optimized for
-the [kramdown](http://kramdown.rubyforge.org/) transformer.
+the [kramdown](https://kramdown.gettalong.org/) transformer.
 
-See the accompanying README. External link targets are referenced at the
-end of this file.
+See the accompanying specs_generation.md. External link targets are referenced
+at the end of this file.
 
 -->
 
@@ -14,6 +14,9 @@ Specification for WebP Lossless Bitstream
 
 _Jyrki Alakuijala, Ph.D., Google, Inc., 2012-06-19_
 
+Paragraphs marked as \[AMENDED\] were amended on 2014-09-16.
+
+Paragraphs marked as \[AMENDED2\] were amended on 2022-05-13.
 
 Abstract
 --------
@@ -24,7 +27,7 @@ exactly, including the color values for zero alpha pixels. The
 format uses subresolution images, recursively embedded into the format
 itself, for storing statistical data about the images, such as the used
 entropy codes, spatial predictors, color space conversion, and color
-table. LZ77, Huffman coding, and a color cache are used for compression
+table. LZ77, prefix coding, and a color cache are used for compression
 of the bulk data. Decoding speeds faster than PNG have been
 demonstrated, as well as 25% denser compression than can be achieved
 using today's PNG format.
@@ -62,9 +65,9 @@ distance mapping
 entropy image
 : A two-dimensional subresolution image indicating which entropy coding
   should be used in a respective square in the image, i.e., each pixel
-  is a meta Huffman code.
+  is a meta prefix code.
 
-Huffman code
+prefix code
 : A classic way to do entropy coding where a smaller number of bits are
   used for more frequent codes.
 
@@ -72,9 +75,9 @@ LZ77
 : Dictionary-based sliding window compression algorithm that either
   emits symbols or describes them as sequences of past symbols.
 
-meta Huffman code
+meta prefix code
 : A small integer (up to 16 bits) that indexes an element in the meta
-  Huffman table.
+  prefix table.
 
 predictor image
 : A two-dimensional subresolution image indicating which spatial
@@ -172,8 +175,8 @@ It should be set to 0 when all alpha values are 255 in the picture, and
 int alpha_is_used = ReadBits(1);
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-The version_number is a 3 bit code that must be discarded by the decoder
-at this time. Complying encoders write a 3-bit value 0.
+The version_number is a 3 bit code that must be set to 0. Any other value
+should be treated as an error. \[AMENDED\]
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 int version_number = ReadBits(3);
@@ -234,7 +237,7 @@ transform, the current pixel value is predicted from the pixels already
 decoded (in scan-line order) and only the residual value (actual -
 predicted) is encoded. The _prediction mode_ determines the type of
 prediction to use. We divide the image into squares and all the pixels
-in a square use same prediction mode.
+in a square use the same prediction mode.
 
 The first 3 bits of prediction data define the block width and height in
 number of bits. The number of block columns, `block_xsize`, is used in
@@ -330,7 +333,7 @@ uint32 Select(uint32 L, uint32 T, uint32 TL) {
            abs(pGreen - GREEN(T)) + abs(pBlue - BLUE(T));
 
   // Return either left or top, the one closer to the prediction.
-  if (pL <= pT) {
+  if (pL < pT) {     // \[AMENDED\]
     return L;
   } else {
     return T;
@@ -366,15 +369,17 @@ the predicted value for the left-topmost pixel of the image is
 0xff000000, L-pixel for all pixels on the top row, and T-pixel for all
 pixels on the leftmost column.
 
+\[AMENDED2\]
 Addressing the TR-pixel for pixels on the rightmost column is
 exceptional. The pixels on the rightmost column are predicted by using
-the modes \[0..13\] just like pixels not on border, but by using the
-leftmost pixel on the same row as the current TR-pixel. The TR-pixel
-offset in memory is the same for border and non-border pixels.
+the modes \[0..13\] just like pixels not on the border, but the leftmost pixel
+on the same row as the current pixel is instead used as the TR-pixel.
 
 
 ### Color Transform
 
+\[AMENDED2\]
+
 The goal of the color transform is to decorrelate the R, G and B values
 of each pixel. Color transform keeps the green (G) value as it is,
 transforms red (R) based on green and transforms blue (B) based on green
@@ -395,8 +400,8 @@ typedef struct {
 The actual color transformation is done by defining a color transform
 delta. The color transform delta depends on the `ColorTransformElement`,
 which is the same for all the pixels in a particular block. The delta is
-added during color transform. The inverse color transform then is just
-subtracting those deltas.
+subtracted during color transform. The inverse color transform then is just
+adding those deltas.
 
 The color transform function is defined as follows:
 
@@ -405,13 +410,13 @@ void ColorTransform(uint8 red, uint8 blue, uint8 green,
                     ColorTransformElement *trans,
                     uint8 *new_red, uint8 *new_blue) {
   // Transformed values of red and blue components
-  uint32 tmp_red = red;
-  uint32 tmp_blue = blue;
+  int tmp_red = red;
+  int tmp_blue = blue;
 
-  // Applying transform is just adding the transform deltas
-  tmp_red  += ColorTransformDelta(trans->green_to_red, green);
-  tmp_blue += ColorTransformDelta(trans->green_to_blue, green);
-  tmp_blue += ColorTransformDelta(trans->red_to_blue, red);
+  // Applying the transform is just subtracting the transform deltas
+  tmp_red  -= ColorTransformDelta(p->green_to_red_,  green);
+  tmp_blue -= ColorTransformDelta(p->green_to_blue_, green);
+  tmp_blue -= ColorTransformDelta(p->red_to_blue_, red);
 
   *new_red = tmp_red & 0xff;
   *new_blue = tmp_blue & 0xff;
@@ -428,6 +433,11 @@ int8 ColorTransformDelta(int8 t, int8 c) {
 }
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+A conversion from the 8-bit unsigned representation (uint8) to the 8-bit
+signed one (int8) is required before calling `ColorTransformDelta()`.
+It should be performed using 8-bit two's complement (that is: uint8 range
+\[128-255\] is mapped to the \[-128, -1\] range of its converted int8 value).
+
 The multiplication is to be done using more precision (with at least
 16-bit dynamics). The sign extension property of the shift operation
 does not matter here: only the lowest 8 bits are used from the result,
@@ -462,14 +472,18 @@ channels.
 void InverseTransform(uint8 red, uint8 green, uint8 blue,
                       ColorTransformElement *p,
                       uint8 *new_red, uint8 *new_blue) {
-  // Applying inverse transform is just subtracting the
-  // color transform deltas
-  red  -= ColorTransformDelta(p->green_to_red_,  green);
-  blue -= ColorTransformDelta(p->green_to_blue_, green);
-  blue -= ColorTransformDelta(p->red_to_blue_, red & 0xff);
+  // Transformed values of red and blue components
+  int tmp_red = red;
+  int tmp_blue = blue;
 
-  *new_red = red & 0xff;
-  *new_blue = blue & 0xff;
+  // Applying inverse transform is just adding the
+  // color transform deltas
+  tmp_red  += ColorTransformDelta(trans->green_to_red, green);
+  tmp_blue += ColorTransformDelta(trans->green_to_blue, green);
+  tmp_blue += ColorTransformDelta(trans->red_to_blue, tmp_red & 0xff);
+
+  *new_red = tmp_red & 0xff;
+  *new_blue = tmp_blue & 0xff;
 }
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -542,6 +556,9 @@ color.
 argb = color_table[GREEN(argb)];
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+If the index is equal or larger than color_table_size, the argb color value
+should be set to 0x00000000 (transparent black).  \[AMENDED\]
+
 When the color table is small (equal to or less than 16 colors), several
 pixels are bundled into a single pixel. The pixel bundling packs several
 (2, 4, or 8) pixels into a single pixel, reducing the image width
@@ -581,12 +598,12 @@ The values are packed into the green component as follows:
     4 most-significant bits of the green value at x / 2.
   * `width_bits` = 2: for every x value where x ≡ 0 (mod 4), a green
     value at x is positioned into the 2 least-significant bits of the
-    green value at x / 4, green values at x + 1 to x + 3 in order to the
-    more significant bits of the green value at x / 4.
+    green value at x / 4, green values at x + 1 to x + 3 are positioned in order
+    to the more significant bits of the green value at x / 4.
   * `width_bits` = 3: for every x value where x ≡ 0 (mod 8), a green
     value at x is positioned into the least-significant bit of the green
-    value at x / 8, green values at x + 1 to x + 7 in order to the more
-    significant bits of the green value at x / 8.
+    value at x / 8, green values at x + 1 to x + 7 are positioned in order to
+    the more significant bits of the green value at x / 8.
 
 
 4 Image Data
@@ -600,8 +617,8 @@ We use image data in five different roles:
 
   1. ARGB image: Stores the actual pixels of the image.
   1. Entropy image: Stores the
-     [meta Huffman codes](#decoding-of-meta-huffman-codes). The red and green
-     components of a pixel define the meta Huffman code used in a particular
+     [meta prefix codes](#decoding-of-meta-prefix-codes). The red and green
+     components of a pixel define the meta prefix code used in a particular
      block of the ARGB image.
   1. Predictor image: Stores the metadata for [Predictor
      Transform](#predictor-transform). The green component of a pixel defines
@@ -612,12 +629,12 @@ We use image data in five different roles:
      the image. Each `ColorTransformElement` `'cte'` is treated as a pixel whose
      alpha component is `255`, red component is `cte.red_to_blue`, green
      component is `cte.green_to_blue` and blue component is `cte.green_to_red`.
-  1. Color indexing image: An array of of size `color_table_size` (up to 256
+  1. Color indexing image: An array of size `color_table_size` (up to 256
      ARGB values) storing the metadata for the
      [Color Indexing Transform](#color-indexing-transform). This is stored as an
      image of width `color_table_size` and height `1`.
 
-### 4.2 Encoding of Image data
+### 4.2 Encoding of Image Data
 
 The encoding of image data is independent of its role.
 
@@ -634,7 +651,7 @@ the image.
 
 Each pixel is encoded using one of the three possible methods:
 
-  1. Huffman coded literal: each channel (green, red, blue and alpha) is
+  1. prefix coded literal: each channel (green, red, blue and alpha) is
      entropy-coded independently;
   2. LZ77 backward reference: a sequence of pixels are copied from elsewhere
      in the image; or
@@ -643,9 +660,9 @@ Each pixel is encoded using one of the three possible methods:
 
 The following sub-sections describe each of these in detail.
 
-#### 4.2.1 Huffman Coded Literals
+#### 4.2.1 Prefix Coded Literals
 
-The pixel is stored as Huffman coded values of green, red, blue and alpha (in
+The pixel is stored as prefix coded values of green, red, blue and alpha (in
 that order). See [this section](#decoding-entropy-coded-image-data) for details.
 
 #### 4.2.2 LZ77 Backward Reference
@@ -669,7 +686,7 @@ very few values in the image. Thus, this approach results in a better
 compression overall.
 
 The following table denotes the prefix codes and extra bits used for storing
-different range of values.
+different ranges of values.
 
 Note: The maximum backward reference length is limited to 4096. Hence, only the
 first 24 prefix codes (with the respective extra bits) are meaningful for length
@@ -744,13 +761,13 @@ The mapping between distance code `i` and the neighboring pixel offset
 (-6, 7), (7, 6),  (-7, 6), (8, 5),  (7, 7),  (-7, 7), (8, 6),  (8, 7)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-For example, distance code `1` indicates offset of `(0, 1)` for the neighboring
-pixel, that is, the pixel above the current pixel (0-pixel difference in
-X-direction and 1 pixel difference in Y-direction). Similarly, distance code
-`3` indicates left-top pixel.
+For example, distance code `1` indicates an offset of `(0, 1)` for the
+neighboring pixel, that is, the pixel above the current pixel (0 pixel
+difference in X-direction and 1 pixel difference in Y-direction). Similarly,
+distance code `3` indicates left-top pixel.
 
-The decoder can convert a distances code 'i' to a scan-line order distance
-'dist' as follows:
+The decoder can convert a distance code `i` to a scan-line order distance
+`dist` as follows:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 (xi, yi) = distance_map[i]
@@ -760,21 +777,22 @@ if (dist < 1) {
 }
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-where 'distance_map' is the mapping noted above and `xsize` is the width of the
+where `distance_map` is the mapping noted above and `xsize` is the width of the
 image in pixels.
 
 
 #### 4.2.3 Color Cache Coding
+{:#color-cache-code}
 
 Color cache stores a set of colors that have been recently used in the image.
 
 **Rationale:** This way, the recently used colors can sometimes be referred to
-more efficiently than emitting them using other two methods (described in
-[4.2.1](#huffman-coded-literals) and [4.2.2](#lz77-backward-reference)).
+more efficiently than emitting them using the other two methods (described in
+[4.2.1](#prefix-coded-literals) and [4.2.2](#lz77-backward-reference)).
 
 Color cache codes are stored as follows. First, there is a 1-bit value that
 indicates if the color cache is used. If this bit is 0, no color cache codes
-exist, and they are not transmitted in the Huffman code that decodes the green
+exist, and they are not transmitted in the prefix code that decodes the green
 symbols and the length prefix codes. However, if this bit is 1, the color cache
 size is read next:
 
@@ -805,130 +823,245 @@ literals, into the cache in the order they appear in the stream.
 
 ### 5.1 Overview
 
-Most of the data is coded using [canonical Huffman code][canonical_huff]. Hence,
-the codes are transmitted by sending the _Huffman code lengths_, as opposed to
-the actual _Huffman codes_.
+Most of the data is coded using a [canonical prefix code][canonical_huff].
+Hence, the codes are transmitted by sending the _prefix code lengths_, as
+opposed to the actual _prefix codes_.
 
-In particular, the format uses **spatially-variant Huffman coding**. In other
+In particular, the format uses **spatially-variant prefix coding**. In other
 words, different blocks of the image can potentially use different entropy
 codes.
 
-**Rationale**: Different areas of the image may have different characteristics. So, allowing them to use different entropy codes provides more flexibility and
-potentially a better compression.
+**Rationale**: Different areas of the image may have different characteristics.
+So, allowing them to use different entropy codes provides more flexibility and
+potentially better compression.
 
 ### 5.2 Details
 
-The encoded image data consists of two parts:
+The encoded image data consists of several parts:
 
-  1. Meta Huffman codes
+  1. Decoding and building the prefix codes \[AMENDED2\]
+  1. Meta prefix codes
   1. Entropy-coded image data
 
-#### 5.2.1 Decoding of Meta Huffman Codes
+#### 5.2.1 Decoding and Building the Prefix Codes
 
-As noted earlier, the format allows the use of different Huffman codes for
-different blocks of the image. _Meta Huffman codes_ are indexes identifying
-which Huffman codes to use in different parts of the image.
+There are several steps in decoding the prefix codes.
 
-Meta Huffman codes may be used _only_ when the image is being used in the
+**Decoding the Code Lengths:**
+{:#decoding-the-code-lengths}
+
+This section describes how to read the prefix code lengths from the bitstream.
+
+The prefix code lengths can be coded in two ways. The method used is specified
+by a 1-bit value.
+
+  * If this bit is 1, it is a _simple code length code_, and
+  * If this bit is 0, it is a _normal code length code_.
+
+In both cases, there can be unused code lengths that are still part of the
+stream. This may be inefficient, but it is allowed by the format.
+
+**(i) Simple Code Length Code:**
+
+\[AMENDED2\]
+
+This variant is used in the special case when only 1 or 2 prefix symbols are
+in the range \[0..255\] with code length `1`. All other prefix code lengths
+are implicitly zeros.
+
+The first bit indicates the number of symbols:
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+int num_symbols = ReadBits(1) + 1;
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Following are the symbol values.
+This first symbol is coded using 1 or 8 bits depending on the value of
+`is_first_8bits`. The range is \[0..1\] or \[0..255\], respectively.
+The second symbol, if present, is always assumed to be in the range \[0..255\]
+and coded using 8 bits.
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+int is_first_8bits = ReadBits(1);
+symbol0 = ReadBits(1 + 7 * is_first_8bits);
+code_lengths[symbol0] = 1;
+if (num_symbols == 2) {
+  symbol1 = ReadBits(8);
+  code_lengths[symbol1] = 1;
+}
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+**Note:** Another special case is when _all_ prefix code lengths are _zeros_
+(an empty prefix code). For example, a prefix code for distance can be empty
+if there are no backward references. Similarly, prefix codes for alpha, red,
+and blue can be empty if all pixels within the same meta prefix code are
+produced using the color cache. However, this case doesn't need a special
+handling, as empty prefix codes can be coded as those containing a single
+symbol `0`.
+
+**(ii) Normal Code Length Code:**
+
+The code lengths of the prefix code fit in 8 bits and are read as follows.
+First, `num_code_lengths` specifies the number of code lengths.
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+int num_code_lengths = 4 + ReadBits(4);
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If `num_code_lengths` is > 18, the bitstream is invalid.
+
+The code lengths are themselves encoded using prefix codes: lower level code
+lengths `code_length_code_lengths` first have to be read. The rest of those
+`code_length_code_lengths` (according to the order in `kCodeLengthCodeOrder`)
+are zeros.
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+int kCodeLengthCodes = 19;
+int kCodeLengthCodeOrder[kCodeLengthCodes] = {
+  17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
+};
+int code_length_code_lengths[kCodeLengthCodes] = { 0 };  // All zeros.
+for (i = 0; i < num_code_lengths; ++i) {
+  code_length_code_lengths[kCodeLengthCodeOrder[i]] = ReadBits(3);
+}
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Next, if `ReadBits(1) == 0`, the maximum number of different read symbols is
+`num_code_lengths`. Otherwise, it is defined as:
+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+int length_nbits = 2 + 2 * ReadBits(3);
+int max_symbol = 2 + ReadBits(length_nbits);
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+A prefix table is then built from `code_length_code_lengths` and used to read
+up to `max_symbol` code lengths.
+
+  * Code \[0..15\] indicates literal code lengths.
+    * Value 0 means no symbols have been coded.
+    * Values \[1..15\] indicate the bit length of the respective code.
+  * Code 16 repeats the previous non-zero value \[3..6\] times, i.e.,
+    `3 + ReadBits(2)` times. If code 16 is used before a non-zero
+    value has been emitted, a value of 8 is repeated.
+  * Code 17 emits a streak of zeros \[3..10\], i.e., `3 + ReadBits(3)`
+    times.
+  * Code 18 emits a streak of zeros of length \[11..138\], i.e.,
+    `11 + ReadBits(7)` times.
+
+Once code lengths are read, a prefix code for each symbol type (A, R, G, B,
+distance) is formed using their respective alphabet sizes:
+
+  * G channel: 256 + 24 + `color_cache_size`
+  * other literals (A,R,B): 256
+  * distance code: 40
+
+#### 5.2.2 Decoding of Meta Prefix Codes
+
+As noted earlier, the format allows the use of different prefix codes for
+different blocks of the image. _Meta prefix codes_ are indexes identifying
+which prefix codes to use in different parts of the image.
+
+Meta prefix codes may be used _only_ when the image is being used in the
 [role](#roles-of-image-data) of an _ARGB image_.
 
-There are two possibilities for the meta Huffman codes, indicated by a 1-bit
+There are two possibilities for the meta prefix codes, indicated by a 1-bit
 value:
 
-  * If this bit is zero, there is only one meta Huffman code used everywhere in
+  * If this bit is zero, there is only one meta prefix code used everywhere in
     the image. No more data is stored.
-  * If this bit is one, the image uses multiple meta Huffman codes. These meta
-    Huffman codes are stored as an _entropy image_ (described below).
+  * If this bit is one, the image uses multiple meta prefix codes. These meta
+    prefix codes are stored as an _entropy image_ (described below).
 
 **Entropy image:**
 
-The entropy image defines which Huffman codes are used in different parts of the
+The entropy image defines which prefix codes are used in different parts of the
 image, as described below.
 
-The first 3-bits contain the `huffman_bits` value. The dimensions of the entropy
-image are derived from 'huffman_bits'.
+The first 3-bits contain the `prefix_bits` value. The dimensions of the entropy
+image are derived from 'prefix_bits'.
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-int huffman_bits = ReadBits(3) + 2;
-int huffman_xsize = DIV_ROUND_UP(xsize, 1 << huffman_bits);
-int huffman_ysize = DIV_ROUND_UP(ysize, 1 << huffman_bits);
+int prefix_bits = ReadBits(3) + 2;
+int prefix_xsize = DIV_ROUND_UP(xsize, 1 << prefix_bits);
+int prefix_ysize = DIV_ROUND_UP(ysize, 1 << prefix_bits);
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 where `DIV_ROUND_UP` is as defined [earlier](#predictor-transform).
 
-Next bits contain an entropy image of width `huffman_xsize` and height
-`huffman_ysize`.
+The next bits contain an entropy image of width `prefix_xsize` and height
+`prefix_ysize`.
 
-**Interpretation of Meta Huffman Codes:**
+**Interpretation of Meta Prefix Codes:**
 
-For any given pixel (x, y), there is a set of five Huffman codes associated with
+For any given pixel (x, y), there is a set of five prefix codes associated with
 it. These codes are (in bitstream order):
 
-  * **Huffman code #1**: used for green channel, backward-reference length and
+  * **prefix code #1**: used for green channel, backward-reference length and
     color cache
-  * **Huffman code #2, #3 and #4**: used for red, blue and alpha channels
+  * **prefix code #2, #3 and #4**: used for red, blue and alpha channels
     respectively.
-  * **Huffman code #5**: used for backward-reference distance.
+  * **prefix code #5**: used for backward-reference distance.
 
-From here on, we refer to this set as a **Huffman code group**.
+From here on, we refer to this set as a **prefix code group**.
 
-The number of Huffman code groups in the ARGB image can be obtained by finding
-the _largest meta Huffman code_ from the entropy image:
+The number of prefix code groups in the ARGB image can be obtained by finding
+the _largest meta prefix code_ from the entropy image:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-int num_huff_groups = max(entropy image) + 1;
+int num_prefix_groups = max(entropy image) + 1;
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-where `max(entropy image)` indicates the largest Huffman code stored in the
+where `max(entropy image)` indicates the largest prefix code stored in the
 entropy image.
 
-As each Huffman code groups contains five Huffman codes, the total number of
-Huffman codes is:
+As each prefix code group contains five prefix codes, the total number of
+prefix codes is:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-int num_huff_codes = 5 * num_huff_groups;
+int num_prefix_codes = 5 * num_prefix_groups;
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Given a pixel (x, y) in the ARGB image, we can obtain the corresponding Huffman
+Given a pixel (x, y) in the ARGB image, we can obtain the corresponding prefix
 codes to be used as follows:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-int position = (y >> huffman_bits) * huffman_xsize + (x >> huffman_bits);
-int meta_huff_code = (entropy_image[pos] >> 8) & 0xffff;
-HuffmanCodeGroup huff_group = huffman_code_groups[meta_huff_code];
+int position = (y >> prefix_bits) * prefix_xsize + (x >> prefix_bits);
+int meta_prefix_code = (entropy_image[pos] >> 8) & 0xffff;
+PrefixCodeGroup prefix_group = prefix_code_groups[meta_prefix_code];
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-where, we have assumed the existence of `HuffmanCodeGroup` structure, which
-represents a set of five Huffman codes. Also, `huffman_code_groups` is an array
-of `HuffmanCodeGroup` (of size `num_huff_groups`).
+where, we have assumed the existence of `PrefixCodeGroup` structure, which
+represents a set of five prefix codes. Also, `prefix_code_groups` is an array
+of `PrefixCodeGroup` (of size `num_prefix_groups`).
 
-The decoder then uses Huffman code group `huff_group` to decode the pixel
+The decoder then uses prefix code group `prefix_group` to decode the pixel
 (x, y) as explained in the [next section](#decoding-entropy-coded-image-data).
 
-#### 5.2.2 Decoding Entropy-coded Image Data
+#### 5.2.3 Decoding Entropy-coded Image Data
+
+\[AMENDED2\]
 
 For the current position (x, y) in the image, the decoder first identifies the
-corresponding Huffman code group (as explained in the last section). Given the
-Huffman code group, the pixel is read and decoded as follows:
+corresponding prefix code group (as explained in the last section). Given the
+prefix code group, the pixel is read and decoded as follows:
 
-Read next symbol S from the bitstream using Huffman code #1. \[See
-[next section](#decoding-the-code-lengths) for details on decoding the Huffman
-code lengths\]. Note that S is any integer in the range `0` to
-`(256 + 24 + ` [`color_cache_size`](#color-cache-code)`- 1)`.
+Read next symbol S from the bitstream using prefix code #1. Note that S is any
+integer in the range `0` to
+`(256 + 24 + ` [`color_cache_size`](#color-cache-code)` - 1)`.
 
 The interpretation of S depends on its value:
 
   1. if S < 256
-     1. Use S as the green component
-     1. Read red from the bitstream using Huffman code #2
-     1. Read blue from the bitstream using Huffman code #3
-     1. Read alpha from the bitstream using Huffman code #4
-  1. if S < 256 + 24
-     1. Use S - 256 as a length prefix code
-     1. Read extra bits for length from the bitstream
+     1. Use S as the green component.
+     1. Read red from the bitstream using prefix code #2.
+     1. Read blue from the bitstream using prefix code #3.
+     1. Read alpha from the bitstream using prefix code #4.
+  1. if S >= 256 && S < 256 + 24
+     1. Use S - 256 as a length prefix code.
+     1. Read extra bits for length from the bitstream.
      1. Determine backward-reference length L from length prefix code and the
         extra bits read.
-     1. Read distance prefix code from the bitstream using Huffman code #5
-     1. Read extra bits for distance from the bitstream
+     1. Read distance prefix code from the bitstream using prefix code #5.
+     1. Read extra bits for distance from the bitstream.
      1. Determine backward-reference distance D from distance prefix code and
         the extra bits read.
      1. Copy the L pixels (in scan-line order) from the sequence of pixels
@@ -938,80 +1071,6 @@ The interpretation of S depends on its value:
      1. Get ARGB color from the color cache at that index.
 
 
-**Decoding the Code Lengths:**
-{:#decoding-the-code-lengths}
-
-This section describes the details about reading a symbol from the bitstream by
-decoding the Huffman code length.
-
-The Huffman code lengths can be coded in two ways. The method used is specified
-by a 1-bit value.
-
-  * If this bit is 1, it is a _simple code length code_, and
-  * If this bit is 0, it is a _normal code length code_.
-
-**(i) Simple Code Length Code:**
-
-This variant is used in the special case when only 1 or 2 Huffman code lengths
-are non-zero, and are in the range of \[0, 255\]. All other Huffman code lengths
-are implicitly zeros.
-
-The first bit indicates the number of non-zero code lengths:
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-int num_code_lengths = ReadBits(1) + 1;
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-The first code length is stored either using a 1-bit code for values of 0 and 1,
-or using an 8-bit code for values in range \[0, 255\]. The second code length,
-when present, is coded as an 8-bit code.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-int is_first_8bits = ReadBits(1);
-code_lengths[0] = ReadBits(1 + 7 * is_first_8bits);
-if (num_code_lengths == 2) {
-  code_lengths[1] = ReadBits(8);
-}
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-**Note:** Another special case is when _all_ Huffman code lengths are _zeros_
-(an empty Huffman code). For example, a Huffman code for distance can be empty
-if there are no backward references. Similarly, Huffman codes for alpha, red,
-and blue can be empty if all pixels within the same meta Huffman code are
-produced using the color cache. However, this case doesn't need a special
-handling, as empty Huffman codes can be coded as those containing a single
-symbol `0`.
-
-**(ii) Normal Code Length Code:**
-
-The code lengths of a Huffman code are read as follows: `num_code_lengths`
-specifies the number of code lengths; the rest of the code lengths
-(according to the order in `kCodeLengthCodeOrder`) are zeros.
-
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-int kCodeLengthCodes = 19;
-int kCodeLengthCodeOrder[kCodeLengthCodes] = {
-  17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15
-};
-int code_lengths[kCodeLengthCodes] = { 0 };  // All zeros.
-int num_code_lengths = 4 + ReadBits(4);
-for (i = 0; i < num_code_lengths; ++i) {
-  code_lengths[kCodeLengthCodeOrder[i]] = ReadBits(3);
-}
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-  * Code length code \[0..15\] indicates literal code lengths.
-    * Value 0 means no symbols have been coded.
-    * Values \[1..15\] indicate the bit length of the respective code.
-  * Code 16 repeats the previous non-zero value \[3..6\] times, i.e.,
-    3 + `ReadBits(2)` times.  If code 16 is used before a non-zero
-    value has been emitted, a value of 8 is repeated.
-  * Code 17 emits a streak of zeros \[3..10\], i.e., 3 + `ReadBits(3)`
-    times.
-  * Code 18 emits a streak of zeros of length \[11..138\], i.e.,
-    11 + `ReadBits(7)` times.
-
-
 6 Overall Structure of the Format
 ---------------------------------
 
@@ -1047,23 +1106,26 @@ of pixels (xsize * ysize).
 
 #### Structure of the Image Data
 
+\[AMENDED2\]
+
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-<spatially-coded image> ::= <meta huffman><entropy-coded image>
-<entropy-coded image> ::= <color cache info><huffman codes><lz77-coded image>
-<meta huffman> ::= 1-bit value 0 |
-                   (1-bit value 1; <entropy image>)
-<entropy image> ::= 3-bit subsample value; <entropy-coded image>
+<spatially-coded image> ::= <color cache info><meta prefix><data>
+<entropy-coded image> ::= <color cache info><data>
 <color cache info> ::= 1 bit value 0 |
                        (1-bit value 1; 4-bit value for color cache size)
-<huffman codes> ::= <huffman code group> | <huffman code group><huffman codes>
-<huffman code group> ::= <huffman code><huffman code><huffman code>
-                         <huffman code><huffman code>
-                         See "Interpretation of Meta Huffman codes" to
-                         understand what each of these five Huffman codes are
-                         for.
-<huffman code> ::= <simple huffman code> | <normal huffman code>
-<simple huffman code> ::= see "Simple code length code" for details
-<normal huffman code> ::= <code length code>; encoded code lengths
+<meta prefix> ::= 1-bit value 0 |
+                  (1-bit value 1; <entropy image>)
+<data> ::= <prefix codes><lz77-coded image>
+<entropy image> ::= 3-bit subsample value; <entropy-coded image>
+<prefix codes> ::= <prefix code group> | <prefix code group><prefix codes>
+<prefix code group> ::= <prefix code><prefix code><prefix code>
+                        <prefix code><prefix code>
+                        See "Interpretation of Meta Prefix Codes" to
+                        understand what each of these five prefix codes are
+                        for.
+<prefix code> ::= <simple prefix code> | <normal prefix code>
+<simple prefix code> ::= see "Simple code length code" for details
+<normal prefix code> ::= <code length code>; encoded code lengths
 <code length code> ::= see section "Normal code length code"
 <lz77-coded image> ::= ((<argb-pixel> | <lz77-copy> | <color-cache-code>)
                        <lz77-coded image>) | ""
@@ -1073,9 +1135,8 @@ A possible example sequence:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 <RIFF header><image size>1-bit value 1<subtract-green-tx>
-1-bit value 1<predictor-tx>1-bit value 0<meta huffman>
-<color cache info><huffman codes>
-<lz77-coded image>
+1-bit value 1<predictor-tx>1-bit value 0<color cache info>1-bit value 0
+<prefix codes><lz77-coded image>
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-[canonical_huff]: http://en.wikipedia.org/wiki/Canonical_Huffman_code
+[canonical_huff]: https://en.wikipedia.org/wiki/Canonical_Huffman_code

examples/Android.mk

@@ -0,0 +1,93 @@
+LOCAL_PATH := $(call my-dir)
+
+################################################################################
+# libexample_util
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    example_util.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
+
+LOCAL_MODULE := example_util
+
+include $(BUILD_STATIC_LIBRARY)
+
+################################################################################
+# cwebp
+
+include $(CLEAR_VARS)
+
+# Note: to enable jpeg/png encoding the sources from AOSP can be used with
+# minor modification to their Android.mk files.
+LOCAL_SRC_FILES := \
+    cwebp.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_STATIC_LIBRARIES := example_util imageio_util imagedec webpdemux webp
+
+LOCAL_MODULE := cwebp
+
+include $(BUILD_EXECUTABLE)
+
+################################################################################
+# dwebp
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    dwebp.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_STATIC_LIBRARIES := example_util imagedec imageenc webpdemux webp
+LOCAL_MODULE := dwebp
+
+include $(BUILD_EXECUTABLE)
+
+################################################################################
+# webpmux
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    webpmux.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_STATIC_LIBRARIES := example_util imageio_util webpmux webp
+
+LOCAL_MODULE := webpmux_example
+
+include $(BUILD_EXECUTABLE)
+
+################################################################################
+# img2webp
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    img2webp.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_STATIC_LIBRARIES := example_util imageio_util imagedec webpmux webpdemux \
+                          webp
+
+LOCAL_MODULE := img2webp_example
+
+include $(BUILD_EXECUTABLE)
+
+################################################################################
+# webpinfo
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    webpinfo.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_STATIC_LIBRARIES := example_util imageio_util webp
+
+LOCAL_MODULE := webpinfo_example
+
+include $(BUILD_EXECUTABLE)

examples/Makefile.am

@@ -1,52 +1,119 @@
-AM_CPPFLAGS = -I$(top_srcdir)/src
+AM_CPPFLAGS += -I$(top_builddir)/src -I$(top_srcdir)/src
 
-bin_PROGRAMS = dwebp cwebp
-if BUILD_VWEBP
-  bin_PROGRAMS += vwebp
+bin_PROGRAMS =
+if BUILD_DEMUX
+  bin_PROGRAMS += dwebp cwebp
 endif
-if WANT_MUX
-  bin_PROGRAMS += webpmux
+if BUILD_ANIMDIFF
+  noinst_PROGRAMS = anim_diff anim_dump
 endif
-
 if BUILD_GIF2WEBP
   bin_PROGRAMS += gif2webp
 endif
+if BUILD_IMG2WEBP
+  bin_PROGRAMS += img2webp
+endif
+if BUILD_MUX
+  bin_PROGRAMS += webpmux
+endif
+if BUILD_VWEBP
+  bin_PROGRAMS += vwebp
+endif
+if BUILD_WEBPINFO
+  bin_PROGRAMS += webpinfo
+endif
 
-noinst_LTLIBRARIES = libexampleutil.la
+noinst_LTLIBRARIES = libexample_util.la
 
-libexampleutil_la_SOURCES = example_util.c example_util.h
+libexample_util_la_SOURCES = example_util.c example_util.h
+libexample_util_la_LIBADD = ../src/libwebp.la
+
+anim_diff_SOURCES = anim_diff.c anim_util.c anim_util.h gifdec.c gifdec.h
+anim_diff_CPPFLAGS = $(AM_CPPFLAGS) $(GIF_INCLUDES)
+anim_diff_LDADD  =
+anim_diff_LDADD += ../src/demux/libwebpdemux.la
+anim_diff_LDADD += libexample_util.la
+anim_diff_LDADD += ../imageio/libimageio_util.la
+anim_diff_LDADD += $(GIF_LIBS) -lm
+
+anim_dump_SOURCES = anim_dump.c anim_util.c anim_util.h gifdec.c gifdec.h
+anim_dump_CPPFLAGS = $(AM_CPPFLAGS) $(PNG_INCLUDES)
+anim_dump_CPPFLAGS += $(GIF_INCLUDES)
+anim_dump_LDADD  =
+anim_dump_LDADD += ../src/demux/libwebpdemux.la
+anim_dump_LDADD += libexample_util.la
+anim_dump_LDADD += ../imageio/libimageio_util.la
+anim_dump_LDADD += ../imageio/libimageenc.la
+anim_dump_LDADD += $(PNG_LIBS) $(GIF_LIBS) $(TIFF_LIBS) -lm
+
+cwebp_SOURCES  = cwebp.c stopwatch.h
+cwebp_CPPFLAGS  = $(AM_CPPFLAGS)
+cwebp_LDADD  =
+cwebp_LDADD += libexample_util.la
+cwebp_LDADD += ../imageio/libimageio_util.la
+cwebp_LDADD += ../imageio/libimagedec.la
+cwebp_LDADD += ../src/libwebp.la
+cwebp_LDADD += $(JPEG_LIBS) $(PNG_LIBS) $(TIFF_LIBS)
 
 dwebp_SOURCES = dwebp.c stopwatch.h
-dwebp_CPPFLAGS  = $(AM_CPPFLAGS) $(USE_EXPERIMENTAL_CODE)
+dwebp_CPPFLAGS  = $(AM_CPPFLAGS)
 dwebp_CPPFLAGS += $(JPEG_INCLUDES) $(PNG_INCLUDES)
-dwebp_LDADD = libexampleutil.la $(PNG_LIBS) $(JPEG_LIBS)
+dwebp_LDADD  =
+dwebp_LDADD += libexample_util.la
+dwebp_LDADD += ../imageio/libimagedec.la
+dwebp_LDADD += ../imageio/libimageenc.la
+dwebp_LDADD += ../imageio/libimageio_util.la
+dwebp_LDADD += ../src/libwebp.la
+dwebp_LDADD +=$(PNG_LIBS) $(JPEG_LIBS)
 
-cwebp_SOURCES  = cwebp.c metadata.c metadata.h stopwatch.h
-cwebp_SOURCES += jpegdec.c jpegdec.h
-cwebp_SOURCES += pngdec.c pngdec.h
-cwebp_SOURCES += tiffdec.c tiffdec.h
-cwebp_SOURCES += wicdec.c wicdec.h
-cwebp_CPPFLAGS  = $(AM_CPPFLAGS) $(USE_EXPERIMENTAL_CODE)
-cwebp_CPPFLAGS += $(JPEG_INCLUDES) $(PNG_INCLUDES) $(TIFF_INCLUDES)
-cwebp_LDADD = ../src/libwebp.la $(JPEG_LIBS) $(PNG_LIBS) $(TIFF_LIBS)
-
-gif2webp_SOURCES = gif2webp.c gif2webp_util.c
-gif2webp_CPPFLAGS = $(AM_CPPFLAGS) $(USE_EXPERIMENTAL_CODE) $(GIF_INCLUDES)
-gif2webp_LDADD  = libexampleutil.la ../src/mux/libwebpmux.la ../src/libwebp.la
+gif2webp_SOURCES = gif2webp.c gifdec.c gifdec.h
+gif2webp_CPPFLAGS = $(AM_CPPFLAGS) $(GIF_INCLUDES)
+gif2webp_LDADD  =
+gif2webp_LDADD += libexample_util.la
+gif2webp_LDADD += ../imageio/libimageio_util.la
+gif2webp_LDADD += ../src/mux/libwebpmux.la
+gif2webp_LDADD += ../src/libwebp.la
 gif2webp_LDADD += $(GIF_LIBS)
 
-webpmux_SOURCES = webpmux.c
-webpmux_CPPFLAGS = $(AM_CPPFLAGS) $(USE_EXPERIMENTAL_CODE)
-webpmux_LDADD = libexampleutil.la ../src/mux/libwebpmux.la ../src/libwebp.la
-
 vwebp_SOURCES = vwebp.c
-vwebp_CPPFLAGS = $(AM_CPPFLAGS) $(USE_EXPERIMENTAL_CODE) $(GL_INCLUDES)
-vwebp_LDADD = libexampleutil.la ../src/demux/libwebpdemux.la $(GL_LIBS)
+vwebp_CPPFLAGS = $(AM_CPPFLAGS) $(GL_INCLUDES)
+vwebp_LDADD  =
+vwebp_LDADD += libexample_util.la
+vwebp_LDADD += ../imageio/libimageio_util.la
+vwebp_LDADD += ../src/demux/libwebpdemux.la
+vwebp_LDADD += $(GL_LIBS)
+
+webpmux_SOURCES = webpmux.c
+webpmux_CPPFLAGS = $(AM_CPPFLAGS)
+webpmux_LDADD  =
+webpmux_LDADD += libexample_util.la
+webpmux_LDADD += ../imageio/libimageio_util.la
+webpmux_LDADD += ../src/mux/libwebpmux.la
+webpmux_LDADD += ../src/libwebp.la
+
+img2webp_SOURCES = img2webp.c
+img2webp_CPPFLAGS = $(AM_CPPFLAGS)
+img2webp_LDADD  =
+img2webp_LDADD += libexample_util.la
+img2webp_LDADD += ../imageio/libimageio_util.la
+img2webp_LDADD += ../imageio/libimagedec.la
+img2webp_LDADD += ../src/mux/libwebpmux.la
+img2webp_LDADD += ../src/libwebp.la
+img2webp_LDADD += $(PNG_LIBS) $(JPEG_LIBS) $(TIFF_LIBS)
+
+webpinfo_SOURCES = webpinfo.c
+webpinfo_CPPFLAGS = $(AM_CPPFLAGS)
+webpinfo_LDADD  =
+webpinfo_LDADD += libexample_util.la
+webpinfo_LDADD += ../imageio/libimageio_util.la
+webpinfo_LDADD += ../src/libwebp.la
 
 if BUILD_LIBWEBPDECODER
-  dwebp_LDADD += ../src/libwebpdecoder.la
+  anim_diff_LDADD += ../src/libwebpdecoder.la
+  anim_dump_LDADD += ../src/libwebpdecoder.la
   vwebp_LDADD += ../src/libwebpdecoder.la
 else
-  dwebp_LDADD += ../src/libwebp.la
+  anim_diff_LDADD += ../src/libwebp.la
+  anim_dump_LDADD += ../src/libwebp.la
   vwebp_LDADD += ../src/libwebp.la
 endif

examples/anim_diff.c

@@ -0,0 +1,317 @@
+// Copyright 2015 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Checks if given pair of animated GIF/WebP images are identical:
+// That is: their reconstructed canvases match pixel-by-pixel and their other
+// animation properties (loop count etc) also match.
+//
+// example: anim_diff foo.gif bar.webp
+
+#include <assert.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>  // for 'strtod'.
+#include <string.h>  // for 'strcmp'.
+
+#include "./anim_util.h"
+#include "./example_util.h"
+#include "./unicode.h"
+
+#if defined(_MSC_VER) && _MSC_VER < 1900
+#define snprintf _snprintf
+#endif
+
+// Returns true if 'a + b' will overflow.
+static int AdditionWillOverflow(int a, int b) {
+  return (b > 0) && (a > INT_MAX - b);
+}
+
+static int FramesAreEqual(const uint8_t* const rgba1,
+                          const uint8_t* const rgba2, int width, int height) {
+  const int stride = width * 4;  // Always true for 'DecodedFrame.rgba'.
+  return !memcmp(rgba1, rgba2, stride * height);
+}
+
+static WEBP_INLINE int PixelsAreSimilar(uint32_t src, uint32_t dst,
+                                        int max_allowed_diff) {
+  const int src_a = (src >> 24) & 0xff;
+  const int src_r = (src >> 16) & 0xff;
+  const int src_g = (src >> 8) & 0xff;
+  const int src_b = (src >> 0) & 0xff;
+  const int dst_a = (dst >> 24) & 0xff;
+  const int dst_r = (dst >> 16) & 0xff;
+  const int dst_g = (dst >> 8) & 0xff;
+  const int dst_b = (dst >> 0) & 0xff;
+
+  return (abs(src_r * src_a - dst_r * dst_a) <= (max_allowed_diff * 255)) &&
+         (abs(src_g * src_a - dst_g * dst_a) <= (max_allowed_diff * 255)) &&
+         (abs(src_b * src_a - dst_b * dst_a) <= (max_allowed_diff * 255)) &&
+         (abs(src_a - dst_a) <= max_allowed_diff);
+}
+
+static int FramesAreSimilar(const uint8_t* const rgba1,
+                            const uint8_t* const rgba2,
+                            int width, int height, int max_allowed_diff) {
+  int i, j;
+  assert(max_allowed_diff > 0);
+  for (j = 0; j < height; ++j) {
+    for (i = 0; i < width; ++i) {
+      const int stride = width * 4;
+      const size_t offset = j * stride + i;
+      if (!PixelsAreSimilar(rgba1[offset], rgba2[offset], max_allowed_diff)) {
+        return 0;
+      }
+    }
+  }
+  return 1;
+}
+
+// Minimize number of frames by combining successive frames that have at max
+// 'max_diff' difference per channel between corresponding pixels.
+static void MinimizeAnimationFrames(AnimatedImage* const img, int max_diff) {
+  uint32_t i;
+  for (i = 1; i < img->num_frames; ++i) {
+    DecodedFrame* const frame1 = &img->frames[i - 1];
+    DecodedFrame* const frame2 = &img->frames[i];
+    const uint8_t* const rgba1 = frame1->rgba;
+    const uint8_t* const rgba2 = frame2->rgba;
+    int should_merge_frames = 0;
+    // If merging frames will result in integer overflow for 'duration',
+    // skip merging.
+    if (AdditionWillOverflow(frame1->duration, frame2->duration)) continue;
+    if (max_diff > 0) {
+      should_merge_frames = FramesAreSimilar(rgba1, rgba2, img->canvas_width,
+                                             img->canvas_height, max_diff);
+    } else {
+      should_merge_frames =
+          FramesAreEqual(rgba1, rgba2, img->canvas_width, img->canvas_height);
+    }
+    if (should_merge_frames) {  // Merge 'i+1'th frame into 'i'th frame.
+      frame1->duration += frame2->duration;
+      if (i + 1 < img->num_frames) {
+        memmove(&img->frames[i], &img->frames[i + 1],
+                (img->num_frames - i - 1) * sizeof(*img->frames));
+      }
+      --img->num_frames;
+      --i;
+    }
+  }
+}
+
+static int CompareValues(uint32_t a, uint32_t b, const char* output_str) {
+  if (a != b) {
+    fprintf(stderr, "%s: %d vs %d\n", output_str, a, b);
+    return 0;
+  }
+  return 1;
+}
+
+static int CompareBackgroundColor(uint32_t bg1, uint32_t bg2, int premultiply) {
+  if (premultiply) {
+    const int alpha1 = (bg1 >> 24) & 0xff;
+    const int alpha2 = (bg2 >> 24) & 0xff;
+    if (alpha1 == 0 && alpha2 == 0) return 1;
+  }
+  if (bg1 != bg2) {
+    fprintf(stderr, "Background color mismatch: 0x%08x vs 0x%08x\n",
+            bg1, bg2);
+    return 0;
+  }
+  return 1;
+}
+
+// Note: As long as frame durations and reconstructed frames are identical, it
+// is OK for other aspects like offsets, dispose/blend method to vary.
+static int CompareAnimatedImagePair(const AnimatedImage* const img1,
+                                    const AnimatedImage* const img2,
+                                    int premultiply,
+                                    double min_psnr) {
+  int ok = 1;
+  const int is_multi_frame_image = (img1->num_frames > 1);
+  uint32_t i;
+
+  ok = CompareValues(img1->canvas_width, img2->canvas_width,
+                     "Canvas width mismatch") && ok;
+  ok = CompareValues(img1->canvas_height, img2->canvas_height,
+                     "Canvas height mismatch") && ok;
+  ok = CompareValues(img1->num_frames, img2->num_frames,
+                     "Frame count mismatch") && ok;
+  if (!ok) return 0;  // These are fatal failures, can't proceed.
+
+  if (is_multi_frame_image) {  // Checks relevant for multi-frame images only.
+    int max_loop_count_workaround = 0;
+    // Transcodes to webp increase the gif loop count by 1 for compatibility.
+    // When the gif has the maximum value the webp value will be off by one.
+    if ((img1->format == ANIM_GIF && img1->loop_count == 65536 &&
+         img2->format == ANIM_WEBP && img2->loop_count == 65535) ||
+        (img1->format == ANIM_WEBP && img1->loop_count == 65535 &&
+         img2->format == ANIM_GIF && img2->loop_count == 65536)) {
+      max_loop_count_workaround = 1;
+    }
+    ok = (max_loop_count_workaround ||
+          CompareValues(img1->loop_count, img2->loop_count,
+                        "Loop count mismatch")) && ok;
+    ok = CompareBackgroundColor(img1->bgcolor, img2->bgcolor,
+                                premultiply) && ok;
+  }
+
+  for (i = 0; i < img1->num_frames; ++i) {
+    // Pixel-by-pixel comparison.
+    const uint8_t* const rgba1 = img1->frames[i].rgba;
+    const uint8_t* const rgba2 = img2->frames[i].rgba;
+    int max_diff;
+    double psnr;
+    if (is_multi_frame_image) {  // Check relevant for multi-frame images only.
+      const char format[] = "Frame #%d, duration mismatch";
+      char tmp[sizeof(format) + 8];
+      ok = ok && (snprintf(tmp, sizeof(tmp), format, i) >= 0);
+      ok = ok && CompareValues(img1->frames[i].duration,
+                               img2->frames[i].duration, tmp);
+    }
+    GetDiffAndPSNR(rgba1, rgba2, img1->canvas_width, img1->canvas_height,
+                   premultiply, &max_diff, &psnr);
+    if (min_psnr > 0.) {
+      if (psnr < min_psnr) {
+        fprintf(stderr, "Frame #%d, psnr = %.2lf (min_psnr = %f)\n", i,
+                psnr, min_psnr);
+        ok = 0;
+      }
+    } else {
+      if (max_diff != 0) {
+        fprintf(stderr, "Frame #%d, max pixel diff: %d\n", i, max_diff);
+        ok = 0;
+      }
+    }
+  }
+  return ok;
+}
+
+static void Help(void) {
+  printf("Usage: anim_diff <image1> <image2> [options]\n");
+  printf("\nOptions:\n");
+  printf("  -dump_frames <folder> dump decoded frames in PAM format\n");
+  printf("  -min_psnr <float> ... minimum per-frame PSNR\n");
+  printf("  -raw_comparison ..... if this flag is not used, RGB is\n");
+  printf("                        premultiplied before comparison\n");
+  printf("  -max_diff <int> ..... maximum allowed difference per channel\n"
+         "                        between corresponding pixels in subsequent\n"
+         "                        frames\n");
+  printf("  -h .................. this help\n");
+  printf("  -version ............ print version number and exit\n");
+}
+
+int main(int argc, const char* argv[]) {
+  int return_code = -1;
+  int dump_frames = 0;
+  const char* dump_folder = NULL;
+  double min_psnr = 0.;
+  int got_input1 = 0;
+  int got_input2 = 0;
+  int premultiply = 1;
+  int max_diff = 0;
+  int i, c;
+  const char* files[2] = { NULL, NULL };
+  AnimatedImage images[2];
+
+  INIT_WARGV(argc, argv);
+
+  for (c = 1; c < argc; ++c) {
+    int parse_error = 0;
+    if (!strcmp(argv[c], "-dump_frames")) {
+      if (c < argc - 1) {
+        dump_frames = 1;
+        dump_folder = (const char*)GET_WARGV(argv, ++c);
+      } else {
+        parse_error = 1;
+      }
+    } else if (!strcmp(argv[c], "-min_psnr")) {
+      if (c < argc - 1) {
+        min_psnr = ExUtilGetFloat(argv[++c], &parse_error);
+      } else {
+        parse_error = 1;
+      }
+    } else if (!strcmp(argv[c], "-raw_comparison")) {
+      premultiply = 0;
+    } else if (!strcmp(argv[c], "-max_diff")) {
+      if (c < argc - 1) {
+        max_diff = ExUtilGetInt(argv[++c], 0, &parse_error);
+      } else {
+        parse_error = 1;
+      }
+    } else if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
+      Help();
+      FREE_WARGV_AND_RETURN(0);
+    } else if (!strcmp(argv[c], "-version")) {
+      int dec_version, demux_version;
+      GetAnimatedImageVersions(&dec_version, &demux_version);
+      printf("WebP Decoder version: %d.%d.%d\nWebP Demux version: %d.%d.%d\n",
+             (dec_version >> 16) & 0xff, (dec_version >> 8) & 0xff,
+             (dec_version >> 0) & 0xff,
+             (demux_version >> 16) & 0xff, (demux_version >> 8) & 0xff,
+             (demux_version >> 0) & 0xff);
+      FREE_WARGV_AND_RETURN(0);
+    } else {
+      if (!got_input1) {
+        files[0] = (const char*)GET_WARGV(argv, c);
+        got_input1 = 1;
+      } else if (!got_input2) {
+        files[1] = (const char*)GET_WARGV(argv, c);
+        got_input2 = 1;
+      } else {
+        parse_error = 1;
+      }
+    }
+    if (parse_error) {
+      Help();
+      FREE_WARGV_AND_RETURN(-1);
+    }
+  }
+  if (argc < 3) {
+    Help();
+    FREE_WARGV_AND_RETURN(-1);
+  }
+
+
+  if (!got_input2) {
+    Help();
+    FREE_WARGV_AND_RETURN(-1);
+  }
+
+  if (dump_frames) {
+    WPRINTF("Dumping decoded frames in: %s\n", (const W_CHAR*)dump_folder);
+  }
+
+  memset(images, 0, sizeof(images));
+  for (i = 0; i < 2; ++i) {
+    WPRINTF("Decoding file: %s\n", (const W_CHAR*)files[i]);
+    if (!ReadAnimatedImage(files[i], &images[i], dump_frames, dump_folder)) {
+      WFPRINTF(stderr, "Error decoding file: %s\n Aborting.\n",
+               (const W_CHAR*)files[i]);
+      return_code = -2;
+      goto End;
+    } else {
+      MinimizeAnimationFrames(&images[i], max_diff);
+    }
+  }
+
+  if (!CompareAnimatedImagePair(&images[0], &images[1],
+                                premultiply, min_psnr)) {
+    WFPRINTF(stderr, "\nFiles %s and %s differ.\n", (const W_CHAR*)files[0],
+             (const W_CHAR*)files[1]);
+    return_code = -3;
+  } else {
+    WPRINTF("\nFiles %s and %s are identical.\n", (const W_CHAR*)files[0],
+            (const W_CHAR*)files[1]);
+    return_code = 0;
+  }
+ End:
+  ClearAnimatedImage(&images[0]);
+  ClearAnimatedImage(&images[1]);
+  FREE_WARGV_AND_RETURN(return_code);
+}

examples/anim_dump.c

@@ -0,0 +1,121 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Decodes an animated WebP file and dumps the decoded frames as PNG or TIFF.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <stdio.h>
+#include <string.h>  // for 'strcmp'.
+
+#include "./anim_util.h"
+#include "webp/decode.h"
+#include "../imageio/image_enc.h"
+#include "./unicode.h"
+
+#if defined(_MSC_VER) && _MSC_VER < 1900
+#define snprintf _snprintf
+#endif
+
+static void Help(void) {
+  printf("Usage: anim_dump [options] files...\n");
+  printf("\nOptions:\n");
+  printf("  -folder <string> .... dump folder (default: '.')\n");
+  printf("  -prefix <string> .... prefix for dumped frames "
+                                  "(default: 'dump_')\n");
+  printf("  -tiff ............... save frames as TIFF\n");
+  printf("  -pam ................ save frames as PAM\n");
+  printf("  -h .................. this help\n");
+  printf("  -version ............ print version number and exit\n");
+}
+
+int main(int argc, const char* argv[]) {
+  int error = 0;
+  const W_CHAR* dump_folder = TO_W_CHAR(".");
+  const W_CHAR* prefix = TO_W_CHAR("dump_");
+  const W_CHAR* suffix = TO_W_CHAR("png");
+  WebPOutputFileFormat format = PNG;
+  int c;
+
+  INIT_WARGV(argc, argv);
+
+  if (argc < 2) {
+    Help();
+    FREE_WARGV_AND_RETURN(-1);
+  }
+
+  for (c = 1; !error && c < argc; ++c) {
+    if (!strcmp(argv[c], "-folder")) {
+      if (c + 1 == argc) {
+        fprintf(stderr, "missing argument after option '%s'\n", argv[c]);
+        error = 1;
+        break;
+      }
+      dump_folder = GET_WARGV(argv, ++c);
+    } else if (!strcmp(argv[c], "-prefix")) {
+      if (c + 1 == argc) {
+        fprintf(stderr, "missing argument after option '%s'\n", argv[c]);
+        error = 1;
+        break;
+      }
+      prefix = GET_WARGV(argv, ++c);
+    } else if (!strcmp(argv[c], "-tiff")) {
+      format = TIFF;
+      suffix = TO_W_CHAR("tiff");
+    } else if (!strcmp(argv[c], "-pam")) {
+      format = PAM;
+      suffix = TO_W_CHAR("pam");
+    } else if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
+      Help();
+      FREE_WARGV_AND_RETURN(0);
+    } else if (!strcmp(argv[c], "-version")) {
+      int dec_version, demux_version;
+      GetAnimatedImageVersions(&dec_version, &demux_version);
+      printf("WebP Decoder version: %d.%d.%d\nWebP Demux version: %d.%d.%d\n",
+             (dec_version >> 16) & 0xff, (dec_version >> 8) & 0xff,
+             (dec_version >> 0) & 0xff,
+             (demux_version >> 16) & 0xff, (demux_version >> 8) & 0xff,
+             (demux_version >> 0) & 0xff);
+      FREE_WARGV_AND_RETURN(0);
+    } else {
+      uint32_t i;
+      AnimatedImage image;
+      const W_CHAR* const file = GET_WARGV(argv, c);
+      memset(&image, 0, sizeof(image));
+      WPRINTF("Decoding file: %s as %s/%sxxxx.%s\n",
+              file, dump_folder, prefix, suffix);
+      if (!ReadAnimatedImage((const char*)file, &image, 0, NULL)) {
+        WFPRINTF(stderr, "Error decoding file: %s\n Aborting.\n", file);
+        error = 1;
+        break;
+      }
+      for (i = 0; !error && i < image.num_frames; ++i) {
+        W_CHAR out_file[1024];
+        WebPDecBuffer buffer;
+        WebPInitDecBuffer(&buffer);
+        buffer.colorspace = MODE_RGBA;
+        buffer.is_external_memory = 1;
+        buffer.width = image.canvas_width;
+        buffer.height = image.canvas_height;
+        buffer.u.RGBA.rgba = image.frames[i].rgba;
+        buffer.u.RGBA.stride = buffer.width * sizeof(uint32_t);
+        buffer.u.RGBA.size = buffer.u.RGBA.stride * buffer.height;
+        WSNPRINTF(out_file, sizeof(out_file), "%s/%s%.4d.%s",
+                  dump_folder, prefix, i, suffix);
+        if (!WebPSaveImage(&buffer, format, (const char*)out_file)) {
+          WFPRINTF(stderr, "Error while saving image '%s'\n", out_file);
+          error = 1;
+        }
+        WebPFreeDecBuffer(&buffer);
+      }
+      ClearAnimatedImage(&image);
+    }
+  }
+  FREE_WARGV_AND_RETURN(error ? 1 : 0);
+}

examples/anim_util.c

@@ -0,0 +1,782 @@
+// Copyright 2015 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Utilities for animated images
+
+#include "./anim_util.h"
+
+#include <assert.h>
+#include <math.h>
+#include <stdio.h>
+#include <string.h>
+
+#if defined(WEBP_HAVE_GIF)
+#include <gif_lib.h>
+#endif
+#include "webp/format_constants.h"
+#include "webp/decode.h"
+#include "webp/demux.h"
+#include "../imageio/imageio_util.h"
+#include "./gifdec.h"
+#include "./unicode.h"
+#include "./unicode_gif.h"
+
+#if defined(_MSC_VER) && _MSC_VER < 1900
+#define snprintf _snprintf
+#endif
+
+static const int kNumChannels = 4;
+
+// -----------------------------------------------------------------------------
+// Common utilities.
+
+#if defined(WEBP_HAVE_GIF)
+// Returns true if the frame covers the full canvas.
+static int IsFullFrame(int width, int height,
+                       int canvas_width, int canvas_height) {
+  return (width == canvas_width && height == canvas_height);
+}
+#endif // WEBP_HAVE_GIF
+
+static int CheckSizeForOverflow(uint64_t size) {
+  return (size == (size_t)size);
+}
+
+static int AllocateFrames(AnimatedImage* const image, uint32_t num_frames) {
+  uint32_t i;
+  uint8_t* mem = NULL;
+  DecodedFrame* frames = NULL;
+  const uint64_t rgba_size =
+      (uint64_t)image->canvas_width * kNumChannels * image->canvas_height;
+  const uint64_t total_size = (uint64_t)num_frames * rgba_size * sizeof(*mem);
+  const uint64_t total_frame_size = (uint64_t)num_frames * sizeof(*frames);
+  if (!CheckSizeForOverflow(total_size) ||
+      !CheckSizeForOverflow(total_frame_size)) {
+    return 0;
+  }
+  mem = (uint8_t*)WebPMalloc((size_t)total_size);
+  frames = (DecodedFrame*)WebPMalloc((size_t)total_frame_size);
+
+  if (mem == NULL || frames == NULL) {
+    WebPFree(mem);
+    WebPFree(frames);
+    return 0;
+  }
+  WebPFree(image->raw_mem);
+  image->num_frames = num_frames;
+  image->frames = frames;
+  for (i = 0; i < num_frames; ++i) {
+    frames[i].rgba = mem + i * rgba_size;
+    frames[i].duration = 0;
+    frames[i].is_key_frame = 0;
+  }
+  image->raw_mem = mem;
+  return 1;
+}
+
+void ClearAnimatedImage(AnimatedImage* const image) {
+  if (image != NULL) {
+    WebPFree(image->raw_mem);
+    WebPFree(image->frames);
+    image->num_frames = 0;
+    image->frames = NULL;
+    image->raw_mem = NULL;
+  }
+}
+
+#if defined(WEBP_HAVE_GIF)
+// Clear the canvas to transparent.
+static void ZeroFillCanvas(uint8_t* rgba,
+                           uint32_t canvas_width, uint32_t canvas_height) {
+  memset(rgba, 0, canvas_width * kNumChannels * canvas_height);
+}
+
+// Clear given frame rectangle to transparent.
+static void ZeroFillFrameRect(uint8_t* rgba, int rgba_stride, int x_offset,
+                              int y_offset, int width, int height) {
+  int j;
+  assert(width * kNumChannels <= rgba_stride);
+  rgba += y_offset * rgba_stride + x_offset * kNumChannels;
+  for (j = 0; j < height; ++j) {
+    memset(rgba, 0, width * kNumChannels);
+    rgba += rgba_stride;
+  }
+}
+
+// Copy width * height pixels from 'src' to 'dst'.
+static void CopyCanvas(const uint8_t* src, uint8_t* dst,
+                       uint32_t width, uint32_t height) {
+  assert(src != NULL && dst != NULL);
+  memcpy(dst, src, width * kNumChannels * height);
+}
+
+// Copy pixels in the given rectangle from 'src' to 'dst' honoring the 'stride'.
+static void CopyFrameRectangle(const uint8_t* src, uint8_t* dst, int stride,
+                               int x_offset, int y_offset,
+                               int width, int height) {
+  int j;
+  const int width_in_bytes = width * kNumChannels;
+  const size_t offset = y_offset * stride + x_offset * kNumChannels;
+  assert(width_in_bytes <= stride);
+  src += offset;
+  dst += offset;
+  for (j = 0; j < height; ++j) {
+    memcpy(dst, src, width_in_bytes);
+    src += stride;
+    dst += stride;
+  }
+}
+#endif // WEBP_HAVE_GIF
+
+// Canonicalize all transparent pixels to transparent black to aid comparison.
+static void CleanupTransparentPixels(uint32_t* rgba,
+                                     uint32_t width, uint32_t height) {
+  const uint32_t* const rgba_end = rgba + width * height;
+  while (rgba < rgba_end) {
+    const uint8_t alpha = (*rgba >> 24) & 0xff;
+    if (alpha == 0) {
+      *rgba = 0;
+    }
+    ++rgba;
+  }
+}
+
+// Dump frame to a PAM file. Returns true on success.
+static int DumpFrame(const char filename[], const char dump_folder[],
+                     uint32_t frame_num, const uint8_t rgba[],
+                     int canvas_width, int canvas_height) {
+  int ok = 0;
+  size_t max_len;
+  int y;
+  const W_CHAR* base_name = NULL;
+  W_CHAR* file_name = NULL;
+  FILE* f = NULL;
+  const char* row;
+
+  if (dump_folder == NULL) dump_folder = (const char*)TO_W_CHAR(".");
+
+  base_name = WSTRRCHR(filename, '/');
+  base_name = (base_name == NULL) ? (const W_CHAR*)filename : base_name + 1;
+  max_len = WSTRLEN(dump_folder) + 1 + WSTRLEN(base_name)
+          + strlen("_frame_") + strlen(".pam") + 8;
+  file_name = (W_CHAR*)WebPMalloc(max_len * sizeof(*file_name));
+  if (file_name == NULL) goto End;
+
+  if (WSNPRINTF(file_name, max_len, "%s/%s_frame_%d.pam",
+                (const W_CHAR*)dump_folder, base_name, frame_num) < 0) {
+    fprintf(stderr, "Error while generating file name\n");
+    goto End;
+  }
+
+  f = WFOPEN(file_name, "wb");
+  if (f == NULL) {
+    WFPRINTF(stderr, "Error opening file for writing: %s\n", file_name);
+    ok = 0;
+    goto End;
+  }
+  if (fprintf(f, "P7\nWIDTH %d\nHEIGHT %d\n"
+              "DEPTH 4\nMAXVAL 255\nTUPLTYPE RGB_ALPHA\nENDHDR\n",
+              canvas_width, canvas_height) < 0) {
+    WFPRINTF(stderr, "Write error for file %s\n", file_name);
+    goto End;
+  }
+  row = (const char*)rgba;
+  for (y = 0; y < canvas_height; ++y) {
+    if (fwrite(row, canvas_width * kNumChannels, 1, f) != 1) {
+      WFPRINTF(stderr, "Error writing to file: %s\n", file_name);
+      goto End;
+    }
+    row += canvas_width * kNumChannels;
+  }
+  ok = 1;
+ End:
+  if (f != NULL) fclose(f);
+  WebPFree(file_name);
+  return ok;
+}
+
+// -----------------------------------------------------------------------------
+// WebP Decoding.
+
+// Returns true if this is a valid WebP bitstream.
+static int IsWebP(const WebPData* const webp_data) {
+  return (WebPGetInfo(webp_data->bytes, webp_data->size, NULL, NULL) != 0);
+}
+
+// Read animated WebP bitstream 'webp_data' into 'AnimatedImage' struct.
+static int ReadAnimatedWebP(const char filename[],
+                            const WebPData* const webp_data,
+                            AnimatedImage* const image, int dump_frames,
+                            const char dump_folder[]) {
+  int ok = 0;
+  int dump_ok = 1;
+  uint32_t frame_index = 0;
+  int prev_frame_timestamp = 0;
+  WebPAnimDecoder* dec;
+  WebPAnimInfo anim_info;
+
+  memset(image, 0, sizeof(*image));
+
+  dec = WebPAnimDecoderNew(webp_data, NULL);
+  if (dec == NULL) {
+    WFPRINTF(stderr, "Error parsing image: %s\n", (const W_CHAR*)filename);
+    goto End;
+  }
+
+  if (!WebPAnimDecoderGetInfo(dec, &anim_info)) {
+    fprintf(stderr, "Error getting global info about the animation\n");
+    goto End;
+  }
+
+  // Animation properties.
+  image->canvas_width = anim_info.canvas_width;
+  image->canvas_height = anim_info.canvas_height;
+  image->loop_count = anim_info.loop_count;
+  image->bgcolor = anim_info.bgcolor;
+
+  // Allocate frames.
+  if (!AllocateFrames(image, anim_info.frame_count)) goto End;
+
+  // Decode frames.
+  while (WebPAnimDecoderHasMoreFrames(dec)) {
+    DecodedFrame* curr_frame;
+    uint8_t* curr_rgba;
+    uint8_t* frame_rgba;
+    int timestamp;
+
+    if (!WebPAnimDecoderGetNext(dec, &frame_rgba, &timestamp)) {
+      fprintf(stderr, "Error decoding frame #%u\n", frame_index);
+      goto End;
+    }
+    assert(frame_index < anim_info.frame_count);
+    curr_frame = &image->frames[frame_index];
+    curr_rgba = curr_frame->rgba;
+    curr_frame->duration = timestamp - prev_frame_timestamp;
+    curr_frame->is_key_frame = 0;  // Unused.
+    memcpy(curr_rgba, frame_rgba,
+           image->canvas_width * kNumChannels * image->canvas_height);
+
+    // Needed only because we may want to compare with GIF later.
+    CleanupTransparentPixels((uint32_t*)curr_rgba,
+                             image->canvas_width, image->canvas_height);
+
+    if (dump_frames && dump_ok) {
+      dump_ok = DumpFrame(filename, dump_folder, frame_index, curr_rgba,
+                          image->canvas_width, image->canvas_height);
+      if (!dump_ok) {  // Print error once, but continue decode loop.
+        fprintf(stderr, "Error dumping frames to %s\n", dump_folder);
+      }
+    }
+
+    ++frame_index;
+    prev_frame_timestamp = timestamp;
+  }
+  ok = dump_ok;
+  if (ok) image->format = ANIM_WEBP;
+
+ End:
+  WebPAnimDecoderDelete(dec);
+  return ok;
+}
+
+// -----------------------------------------------------------------------------
+// GIF Decoding.
+
+#if defined(WEBP_HAVE_GIF)
+
+// Returns true if this is a valid GIF bitstream.
+static int IsGIF(const WebPData* const data) {
+  return data->size > GIF_STAMP_LEN &&
+         (!memcmp(GIF_STAMP, data->bytes, GIF_STAMP_LEN) ||
+          !memcmp(GIF87_STAMP, data->bytes, GIF_STAMP_LEN) ||
+          !memcmp(GIF89_STAMP, data->bytes, GIF_STAMP_LEN));
+}
+
+// GIFLIB_MAJOR is only defined in libgif >= 4.2.0.
+#if defined(GIFLIB_MAJOR) && defined(GIFLIB_MINOR)
+# define LOCAL_GIF_VERSION ((GIFLIB_MAJOR << 8) | GIFLIB_MINOR)
+# define LOCAL_GIF_PREREQ(maj, min) \
+    (LOCAL_GIF_VERSION >= (((maj) << 8) | (min)))
+#else
+# define LOCAL_GIF_VERSION 0
+# define LOCAL_GIF_PREREQ(maj, min) 0
+#endif
+
+#if !LOCAL_GIF_PREREQ(5, 0)
+
+// Added in v5.0
+typedef struct {
+  int DisposalMode;
+#define DISPOSAL_UNSPECIFIED      0       // No disposal specified
+#define DISPOSE_DO_NOT            1       // Leave image in place
+#define DISPOSE_BACKGROUND        2       // Set area to background color
+#define DISPOSE_PREVIOUS          3       // Restore to previous content
+  int UserInputFlag;       // User confirmation required before disposal
+  int DelayTime;           // Pre-display delay in 0.01sec units
+  int TransparentColor;    // Palette index for transparency, -1 if none
+#define NO_TRANSPARENT_COLOR     -1
+} GraphicsControlBlock;
+
+static int DGifExtensionToGCB(const size_t GifExtensionLength,
+                              const GifByteType* GifExtension,
+                              GraphicsControlBlock* gcb) {
+  if (GifExtensionLength != 4) {
+    return GIF_ERROR;
+  }
+  gcb->DisposalMode = (GifExtension[0] >> 2) & 0x07;
+  gcb->UserInputFlag = (GifExtension[0] & 0x02) != 0;
+  gcb->DelayTime = GifExtension[1] | (GifExtension[2] << 8);
+  if (GifExtension[0] & 0x01) {
+    gcb->TransparentColor = (int)GifExtension[3];
+  } else {
+    gcb->TransparentColor = NO_TRANSPARENT_COLOR;
+  }
+  return GIF_OK;
+}
+
+static int DGifSavedExtensionToGCB(GifFileType* GifFile, int ImageIndex,
+                                   GraphicsControlBlock* gcb) {
+  int i;
+  if (ImageIndex < 0 || ImageIndex > GifFile->ImageCount - 1) {
+    return GIF_ERROR;
+  }
+  gcb->DisposalMode = DISPOSAL_UNSPECIFIED;
+  gcb->UserInputFlag = 0;
+  gcb->DelayTime = 0;
+  gcb->TransparentColor = NO_TRANSPARENT_COLOR;
+
+  for (i = 0; i < GifFile->SavedImages[ImageIndex].ExtensionBlockCount; i++) {
+    ExtensionBlock* ep = &GifFile->SavedImages[ImageIndex].ExtensionBlocks[i];
+    if (ep->Function == GRAPHICS_EXT_FUNC_CODE) {
+      return DGifExtensionToGCB(
+          ep->ByteCount, (const GifByteType*)ep->Bytes, gcb);
+    }
+  }
+  return GIF_ERROR;
+}
+
+#define CONTINUE_EXT_FUNC_CODE 0x00
+
+// Signature was changed in v5.0
+#define DGifOpenFileName(a, b) DGifOpenFileName(a)
+
+#endif  // !LOCAL_GIF_PREREQ(5, 0)
+
+// Signature changed in v5.1
+#if !LOCAL_GIF_PREREQ(5, 1)
+#define DGifCloseFile(a, b) DGifCloseFile(a)
+#endif
+
+static int IsKeyFrameGIF(const GifImageDesc* prev_desc, int prev_dispose,
+                         const DecodedFrame* const prev_frame,
+                         int canvas_width, int canvas_height) {
+  if (prev_frame == NULL) return 1;
+  if (prev_dispose == DISPOSE_BACKGROUND) {
+    if (IsFullFrame(prev_desc->Width, prev_desc->Height,
+                    canvas_width, canvas_height)) {
+      return 1;
+    }
+    if (prev_frame->is_key_frame) return 1;
+  }
+  return 0;
+}
+
+static int GetTransparentIndexGIF(GifFileType* gif) {
+  GraphicsControlBlock first_gcb;
+  memset(&first_gcb, 0, sizeof(first_gcb));
+  DGifSavedExtensionToGCB(gif, 0, &first_gcb);
+  return first_gcb.TransparentColor;
+}
+
+static uint32_t GetBackgroundColorGIF(GifFileType* gif) {
+  const int transparent_index = GetTransparentIndexGIF(gif);
+  const ColorMapObject* const color_map = gif->SColorMap;
+  if (transparent_index != NO_TRANSPARENT_COLOR &&
+      gif->SBackGroundColor == transparent_index) {
+    return 0x00000000;  // Special case: transparent black.
+  } else if (color_map == NULL || color_map->Colors == NULL
+             || gif->SBackGroundColor >= color_map->ColorCount) {
+    return 0xffffffff;  // Invalid: assume white.
+  } else {
+    const GifColorType color = color_map->Colors[gif->SBackGroundColor];
+    return (0xffu << 24) |
+           (color.Red << 16) |
+           (color.Green << 8) |
+           (color.Blue << 0);
+  }
+}
+
+// Find appropriate app extension and get loop count from the next extension.
+// We use Chrome's interpretation of the 'loop_count' semantics:
+//   if not present -> loop once
+//   if present and loop_count == 0, return 0 ('infinite').
+//   if present and loop_count != 0, it's the number of *extra* loops
+//     so we need to return loop_count + 1 as total loop number.
+static uint32_t GetLoopCountGIF(const GifFileType* const gif) {
+  int i;
+  for (i = 0; i < gif->ImageCount; ++i) {
+    const SavedImage* const image = &gif->SavedImages[i];
+    int j;
+    for (j = 0; (j + 1) < image->ExtensionBlockCount; ++j) {
+      const ExtensionBlock* const eb1 = image->ExtensionBlocks + j;
+      const ExtensionBlock* const eb2 = image->ExtensionBlocks + j + 1;
+      const char* const signature = (const char*)eb1->Bytes;
+      const int signature_is_ok =
+          (eb1->Function == APPLICATION_EXT_FUNC_CODE) &&
+          (eb1->ByteCount == 11) &&
+          (!memcmp(signature, "NETSCAPE2.0", 11) ||
+           !memcmp(signature, "ANIMEXTS1.0", 11));
+      if (signature_is_ok &&
+          eb2->Function == CONTINUE_EXT_FUNC_CODE && eb2->ByteCount >= 3 &&
+          eb2->Bytes[0] == 1) {
+        const uint32_t extra_loop = ((uint32_t)(eb2->Bytes[2]) << 8) +
+                                    ((uint32_t)(eb2->Bytes[1]) << 0);
+        return (extra_loop > 0) ? extra_loop + 1 : 0;
+      }
+    }
+  }
+  return 1;  // Default.
+}
+
+// Get duration of 'n'th frame in milliseconds.
+static int GetFrameDurationGIF(GifFileType* gif, int n) {
+  GraphicsControlBlock gcb;
+  memset(&gcb, 0, sizeof(gcb));
+  DGifSavedExtensionToGCB(gif, n, &gcb);
+  return gcb.DelayTime * 10;
+}
+
+// Returns true if frame 'target' completely covers 'covered'.
+static int CoversFrameGIF(const GifImageDesc* const target,
+                          const GifImageDesc* const covered) {
+  return target->Left <= covered->Left &&
+         covered->Left + covered->Width <= target->Left + target->Width &&
+         target->Top <= covered->Top &&
+         covered->Top + covered->Height <= target->Top + target->Height;
+}
+
+static void RemapPixelsGIF(const uint8_t* const src,
+                           const ColorMapObject* const cmap,
+                           int transparent_color, int len, uint8_t* dst) {
+  int i;
+  for (i = 0; i < len; ++i) {
+    if (src[i] != transparent_color) {
+      // If a pixel in the current frame is transparent, we don't modify it, so
+      // that we can see-through the corresponding pixel from an earlier frame.
+      const GifColorType c = cmap->Colors[src[i]];
+      dst[4 * i + 0] = c.Red;
+      dst[4 * i + 1] = c.Green;
+      dst[4 * i + 2] = c.Blue;
+      dst[4 * i + 3] = 0xff;
+    }
+  }
+}
+
+static int ReadFrameGIF(const SavedImage* const gif_image,
+                        const ColorMapObject* cmap, int transparent_color,
+                        int out_stride, uint8_t* const dst) {
+  const GifImageDesc* image_desc = &gif_image->ImageDesc;
+  const uint8_t* in;
+  uint8_t* out;
+  int j;
+
+  if (image_desc->ColorMap) cmap = image_desc->ColorMap;
+
+  if (cmap == NULL || cmap->ColorCount != (1 << cmap->BitsPerPixel)) {
+    fprintf(stderr, "Potentially corrupt color map.\n");
+    return 0;
+  }
+
+  in = (const uint8_t*)gif_image->RasterBits;
+  out = dst + image_desc->Top * out_stride + image_desc->Left * kNumChannels;
+
+  for (j = 0; j < image_desc->Height; ++j) {
+    RemapPixelsGIF(in, cmap, transparent_color, image_desc->Width, out);
+    in += image_desc->Width;
+    out += out_stride;
+  }
+  return 1;
+}
+
+// Read animated GIF bitstream from 'filename' into 'AnimatedImage' struct.
+static int ReadAnimatedGIF(const char filename[], AnimatedImage* const image,
+                           int dump_frames, const char dump_folder[]) {
+  uint32_t frame_count;
+  uint32_t canvas_width, canvas_height;
+  uint32_t i;
+  int gif_error;
+  GifFileType* gif;
+
+  gif = DGifOpenFileUnicode((const W_CHAR*)filename, NULL);
+  if (gif == NULL) {
+    WFPRINTF(stderr, "Could not read file: %s.\n", (const W_CHAR*)filename);
+    return 0;
+  }
+
+  gif_error = DGifSlurp(gif);
+  if (gif_error != GIF_OK) {
+    WFPRINTF(stderr, "Could not parse image: %s.\n", (const W_CHAR*)filename);
+    GIFDisplayError(gif, gif_error);
+    DGifCloseFile(gif, NULL);
+    return 0;
+  }
+
+  // Animation properties.
+  image->canvas_width = (uint32_t)gif->SWidth;
+  image->canvas_height = (uint32_t)gif->SHeight;
+  if (image->canvas_width > MAX_CANVAS_SIZE ||
+      image->canvas_height > MAX_CANVAS_SIZE) {
+    fprintf(stderr, "Invalid canvas dimension: %d x %d\n",
+            image->canvas_width, image->canvas_height);
+    DGifCloseFile(gif, NULL);
+    return 0;
+  }
+  image->loop_count = GetLoopCountGIF(gif);
+  image->bgcolor = GetBackgroundColorGIF(gif);
+
+  frame_count = (uint32_t)gif->ImageCount;
+  if (frame_count == 0) {
+    DGifCloseFile(gif, NULL);
+    return 0;
+  }
+
+  if (image->canvas_width == 0 || image->canvas_height == 0) {
+    image->canvas_width = gif->SavedImages[0].ImageDesc.Width;
+    image->canvas_height = gif->SavedImages[0].ImageDesc.Height;
+    gif->SavedImages[0].ImageDesc.Left = 0;
+    gif->SavedImages[0].ImageDesc.Top = 0;
+    if (image->canvas_width == 0 || image->canvas_height == 0) {
+      fprintf(stderr, "Invalid canvas size in GIF.\n");
+      DGifCloseFile(gif, NULL);
+      return 0;
+    }
+  }
+  // Allocate frames.
+  if (!AllocateFrames(image, frame_count)) {
+    DGifCloseFile(gif, NULL);
+    return 0;
+  }
+
+  canvas_width = image->canvas_width;
+  canvas_height = image->canvas_height;
+
+  // Decode and reconstruct frames.
+  for (i = 0; i < frame_count; ++i) {
+    const int canvas_width_in_bytes = canvas_width * kNumChannels;
+    const SavedImage* const curr_gif_image = &gif->SavedImages[i];
+    GraphicsControlBlock curr_gcb;
+    DecodedFrame* curr_frame;
+    uint8_t* curr_rgba;
+
+    memset(&curr_gcb, 0, sizeof(curr_gcb));
+    DGifSavedExtensionToGCB(gif, i, &curr_gcb);
+
+    curr_frame = &image->frames[i];
+    curr_rgba = curr_frame->rgba;
+    curr_frame->duration = GetFrameDurationGIF(gif, i);
+    // Force frames with a small or no duration to 100ms to be consistent
+    // with web browsers and other transcoding tools (like gif2webp itself).
+    if (curr_frame->duration <= 10) curr_frame->duration = 100;
+
+    if (i == 0) {  // Initialize as transparent.
+      curr_frame->is_key_frame = 1;
+      ZeroFillCanvas(curr_rgba, canvas_width, canvas_height);
+    } else {
+      DecodedFrame* const prev_frame = &image->frames[i - 1];
+      const GifImageDesc* const prev_desc = &gif->SavedImages[i - 1].ImageDesc;
+      GraphicsControlBlock prev_gcb;
+      memset(&prev_gcb, 0, sizeof(prev_gcb));
+      DGifSavedExtensionToGCB(gif, i - 1, &prev_gcb);
+
+      curr_frame->is_key_frame =
+          IsKeyFrameGIF(prev_desc, prev_gcb.DisposalMode, prev_frame,
+                        canvas_width, canvas_height);
+
+      if (curr_frame->is_key_frame) {  // Initialize as transparent.
+        ZeroFillCanvas(curr_rgba, canvas_width, canvas_height);
+      } else {
+        int prev_frame_disposed, curr_frame_opaque;
+        int prev_frame_completely_covered;
+        // Initialize with previous canvas.
+        uint8_t* const prev_rgba = image->frames[i - 1].rgba;
+        CopyCanvas(prev_rgba, curr_rgba, canvas_width, canvas_height);
+
+        // Dispose previous frame rectangle.
+        prev_frame_disposed =
+            (prev_gcb.DisposalMode == DISPOSE_BACKGROUND ||
+             prev_gcb.DisposalMode == DISPOSE_PREVIOUS);
+        curr_frame_opaque =
+            (curr_gcb.TransparentColor == NO_TRANSPARENT_COLOR);
+        prev_frame_completely_covered =
+            curr_frame_opaque &&
+            CoversFrameGIF(&curr_gif_image->ImageDesc, prev_desc);
+
+        if (prev_frame_disposed && !prev_frame_completely_covered) {
+          switch (prev_gcb.DisposalMode) {
+            case DISPOSE_BACKGROUND: {
+              ZeroFillFrameRect(curr_rgba, canvas_width_in_bytes,
+                                prev_desc->Left, prev_desc->Top,
+                                prev_desc->Width, prev_desc->Height);
+              break;
+            }
+            case DISPOSE_PREVIOUS: {
+              int src_frame_num = i - 2;
+              while (src_frame_num >= 0) {
+                GraphicsControlBlock src_frame_gcb;
+                memset(&src_frame_gcb, 0, sizeof(src_frame_gcb));
+                DGifSavedExtensionToGCB(gif, src_frame_num, &src_frame_gcb);
+                if (src_frame_gcb.DisposalMode != DISPOSE_PREVIOUS) break;
+                --src_frame_num;
+              }
+              if (src_frame_num >= 0) {
+                // Restore pixels inside previous frame rectangle to
+                // corresponding pixels in source canvas.
+                uint8_t* const src_frame_rgba =
+                    image->frames[src_frame_num].rgba;
+                CopyFrameRectangle(src_frame_rgba, curr_rgba,
+                                   canvas_width_in_bytes,
+                                   prev_desc->Left, prev_desc->Top,
+                                   prev_desc->Width, prev_desc->Height);
+              } else {
+                // Source canvas doesn't exist. So clear previous frame
+                // rectangle to background.
+                ZeroFillFrameRect(curr_rgba, canvas_width_in_bytes,
+                                  prev_desc->Left, prev_desc->Top,
+                                  prev_desc->Width, prev_desc->Height);
+              }
+              break;
+            }
+            default:
+              break;  // Nothing to do.
+          }
+        }
+      }
+    }
+
+    // Decode current frame.
+    if (!ReadFrameGIF(curr_gif_image, gif->SColorMap, curr_gcb.TransparentColor,
+                      canvas_width_in_bytes, curr_rgba)) {
+      DGifCloseFile(gif, NULL);
+      return 0;
+    }
+
+    if (dump_frames) {
+      if (!DumpFrame(filename, dump_folder, i, curr_rgba,
+                     canvas_width, canvas_height)) {
+        DGifCloseFile(gif, NULL);
+        return 0;
+      }
+    }
+  }
+  image->format = ANIM_GIF;
+  DGifCloseFile(gif, NULL);
+  return 1;
+}
+
+#else
+
+static int IsGIF(const WebPData* const data) {
+  (void)data;
+  return 0;
+}
+
+static int ReadAnimatedGIF(const char filename[], AnimatedImage* const image,
+                           int dump_frames, const char dump_folder[]) {
+  (void)filename;
+  (void)image;
+  (void)dump_frames;
+  (void)dump_folder;
+  fprintf(stderr, "GIF support not compiled. Please install the libgif-dev "
+          "package before building.\n");
+  return 0;
+}
+
+#endif  // WEBP_HAVE_GIF
+
+// -----------------------------------------------------------------------------
+
+int ReadAnimatedImage(const char filename[], AnimatedImage* const image,
+                      int dump_frames, const char dump_folder[]) {
+  int ok = 0;
+  WebPData webp_data;
+
+  WebPDataInit(&webp_data);
+  memset(image, 0, sizeof(*image));
+
+  if (!ImgIoUtilReadFile(filename, &webp_data.bytes, &webp_data.size)) {
+    WFPRINTF(stderr, "Error reading file: %s\n", (const W_CHAR*)filename);
+    return 0;
+  }
+
+  if (IsWebP(&webp_data)) {
+    ok = ReadAnimatedWebP(filename, &webp_data, image, dump_frames,
+                          dump_folder);
+  } else if (IsGIF(&webp_data)) {
+    ok = ReadAnimatedGIF(filename, image, dump_frames, dump_folder);
+  } else {
+    WFPRINTF(stderr,
+             "Unknown file type: %s. Supported file types are WebP and GIF\n",
+             (const W_CHAR*)filename);
+    ok = 0;
+  }
+  if (!ok) ClearAnimatedImage(image);
+  WebPDataClear(&webp_data);
+  return ok;
+}
+
+static void Accumulate(double v1, double v2, double* const max_diff,
+                       double* const sse) {
+  const double diff = fabs(v1 - v2);
+  if (diff > *max_diff) *max_diff = diff;
+  *sse += diff * diff;
+}
+
+void GetDiffAndPSNR(const uint8_t rgba1[], const uint8_t rgba2[],
+                    uint32_t width, uint32_t height, int premultiply,
+                    int* const max_diff, double* const psnr) {
+  const uint32_t stride = width * kNumChannels;
+  const int kAlphaChannel = kNumChannels - 1;
+  double f_max_diff = 0.;
+  double sse = 0.;
+  uint32_t x, y;
+  for (y = 0; y < height; ++y) {
+    for (x = 0; x < stride; x += kNumChannels) {
+      int k;
+      const size_t offset = (size_t)y * stride + x;
+      const int alpha1 = rgba1[offset + kAlphaChannel];
+      const int alpha2 = rgba2[offset + kAlphaChannel];
+      Accumulate(alpha1, alpha2, &f_max_diff, &sse);
+      if (!premultiply) {
+        for (k = 0; k < kAlphaChannel; ++k) {
+          Accumulate(rgba1[offset + k], rgba2[offset + k], &f_max_diff, &sse);
+        }
+      } else {
+        // premultiply R/G/B channels with alpha value
+        for (k = 0; k < kAlphaChannel; ++k) {
+          Accumulate(rgba1[offset + k] * alpha1 / 255.,
+                     rgba2[offset + k] * alpha2 / 255.,
+                     &f_max_diff, &sse);
+        }
+      }
+    }
+  }
+  *max_diff = (int)f_max_diff;
+  if (*max_diff == 0) {
+    *psnr = 99.;  // PSNR when images are identical.
+  } else {
+    sse /= stride * height;
+    *psnr = 4.3429448 * log(255. * 255. / sse);
+  }
+}
+
+void GetAnimatedImageVersions(int* const decoder_version,
+                              int* const demux_version) {
+  *decoder_version = WebPGetDecoderVersion();
+  *demux_version = WebPGetDemuxVersion();
+}

examples/anim_util.h

@@ -0,0 +1,73 @@
+// Copyright 2015 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Utilities for animated images
+
+#ifndef WEBP_EXAMPLES_ANIM_UTIL_H_
+#define WEBP_EXAMPLES_ANIM_UTIL_H_
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#include "webp/types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum {
+  ANIM_GIF,
+  ANIM_WEBP
+} AnimatedFileFormat;
+
+typedef struct {
+  uint8_t* rgba;         // Decoded and reconstructed full frame.
+  int duration;          // Frame duration in milliseconds.
+  int is_key_frame;      // True if this frame is a key-frame.
+} DecodedFrame;
+
+typedef struct {
+  AnimatedFileFormat format;
+  uint32_t canvas_width;
+  uint32_t canvas_height;
+  uint32_t bgcolor;
+  uint32_t loop_count;
+  DecodedFrame* frames;
+  uint32_t num_frames;
+  void* raw_mem;
+} AnimatedImage;
+
+// Deallocate everything in 'image' (but not the object itself).
+void ClearAnimatedImage(AnimatedImage* const image);
+
+// Read animated image file into 'AnimatedImage' struct.
+// If 'dump_frames' is true, dump frames to 'dump_folder'.
+// Previous content of 'image' is obliterated.
+// Upon successful return, content of 'image' must be deleted by
+// calling 'ClearAnimatedImage'.
+int ReadAnimatedImage(const char filename[], AnimatedImage* const image,
+                      int dump_frames, const char dump_folder[]);
+
+// Given two RGBA buffers, calculate max pixel difference and PSNR.
+// If 'premultiply' is true, R/G/B values will be pre-multiplied by the
+// transparency before comparison.
+void GetDiffAndPSNR(const uint8_t rgba1[], const uint8_t rgba2[],
+                    uint32_t width, uint32_t height, int premultiply,
+                    int* const max_diff, double* const psnr);
+
+// Return library versions used by anim_util.
+void GetAnimatedImageVersions(int* const decoder_version,
+                              int* const demux_version);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_EXAMPLES_ANIM_UTIL_H_

examples/dwebp.c

@@ -17,37 +17,17 @@
 #include <string.h>
 
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include "webp/config.h"
 #endif
 
-#ifdef WEBP_HAVE_PNG
-#include <png.h>
-#endif
-
-#ifdef HAVE_WINCODEC_H
-#ifdef __MINGW32__
-#define INITGUID  // Without this GUIDs are declared extern and fail to link
-#endif
-#define CINTERFACE
-#define COBJMACROS
-#define _WIN32_IE 0x500  // Workaround bug in shlwapi.h when compiling C++
-                         // code with COBJMACROS.
-#include <ole2.h>  // CreateStreamOnHGlobal()
-#include <shlwapi.h>
-#include <windows.h>
-#include <wincodec.h>
-#endif
-
-#if defined(_WIN32)
-#include <fcntl.h>   // for _O_BINARY
-#include <io.h>      // for _setmode()
-#endif
-
-#include "webp/decode.h"
-#include "./example_util.h"
+#include "../examples/example_util.h"
+#include "../imageio/image_enc.h"
+#include "../imageio/webpdec.h"
 #include "./stopwatch.h"
+#include "./unicode.h"
 
 static int verbose = 0;
+static int quiet = 0;
 #ifndef WEBP_DLL
 #ifdef __cplusplus
 extern "C" {
@@ -60,470 +40,25 @@ extern void* VP8GetCPUInfo;   // opaque forward declaration.
 #endif
 #endif  // WEBP_DLL
 
-//------------------------------------------------------------------------------
-
-// Output types
-typedef enum {
-  PNG = 0,
-  PAM,
-  PPM,
-  PGM,
-  BMP,
-  TIFF,
-  YUV,
-  ALPHA_PLANE_ONLY  // this is for experimenting only
-} OutputFileFormat;
-
-#ifdef HAVE_WINCODEC_H
-
-#define IFS(fn)                                                     \
-  do {                                                              \
-    if (SUCCEEDED(hr)) {                                            \
-      hr = (fn);                                                    \
-      if (FAILED(hr)) fprintf(stderr, #fn " failed %08lx\n", hr);   \
-    }                                                               \
-  } while (0)
-
-#ifdef __cplusplus
-#define MAKE_REFGUID(x) (x)
-#else
-#define MAKE_REFGUID(x) &(x)
-#endif
-
-static HRESULT CreateOutputStream(const char* out_file_name,
-                                  int write_to_mem, IStream** stream) {
-  HRESULT hr = S_OK;
-  if (write_to_mem) {
-    // Output to a memory buffer. This is freed when 'stream' is released.
-    IFS(CreateStreamOnHGlobal(NULL, TRUE, stream));
-  } else {
-    IFS(SHCreateStreamOnFileA(out_file_name, STGM_WRITE | STGM_CREATE, stream));
-  }
-  if (FAILED(hr)) {
-    fprintf(stderr, "Error opening output file %s (%08lx)\n",
-            out_file_name, hr);
-  }
-  return hr;
-}
-
-static HRESULT WriteUsingWIC(const char* out_file_name, int use_stdout,
-                             REFGUID container_guid,
-                             uint8_t* rgb, int stride,
-                             uint32_t width, uint32_t height, int has_alpha) {
-  HRESULT hr = S_OK;
-  IWICImagingFactory* factory = NULL;
-  IWICBitmapFrameEncode* frame = NULL;
-  IWICBitmapEncoder* encoder = NULL;
-  IStream* stream = NULL;
-  WICPixelFormatGUID pixel_format = has_alpha ? GUID_WICPixelFormat32bppBGRA
-                                              : GUID_WICPixelFormat24bppBGR;
-
-  IFS(CoInitialize(NULL));
-  IFS(CoCreateInstance(MAKE_REFGUID(CLSID_WICImagingFactory), NULL,
-                       CLSCTX_INPROC_SERVER,
-                       MAKE_REFGUID(IID_IWICImagingFactory),
-                       (LPVOID*)&factory));
-  if (hr == REGDB_E_CLASSNOTREG) {
-    fprintf(stderr,
-            "Couldn't access Windows Imaging Component (are you running "
-            "Windows XP SP3 or newer?). PNG support not available. "
-            "Use -ppm or -pgm for available PPM and PGM formats.\n");
-  }
-  IFS(CreateOutputStream(out_file_name, use_stdout, &stream));
-  IFS(IWICImagingFactory_CreateEncoder(factory, container_guid, NULL,
-                                       &encoder));
-  IFS(IWICBitmapEncoder_Initialize(encoder, stream,
-                                   WICBitmapEncoderNoCache));
-  IFS(IWICBitmapEncoder_CreateNewFrame(encoder, &frame, NULL));
-  IFS(IWICBitmapFrameEncode_Initialize(frame, NULL));
-  IFS(IWICBitmapFrameEncode_SetSize(frame, width, height));
-  IFS(IWICBitmapFrameEncode_SetPixelFormat(frame, &pixel_format));
-  IFS(IWICBitmapFrameEncode_WritePixels(frame, height, stride,
-                                        height * stride, rgb));
-  IFS(IWICBitmapFrameEncode_Commit(frame));
-  IFS(IWICBitmapEncoder_Commit(encoder));
-
-  if (SUCCEEDED(hr) && use_stdout) {
-    HGLOBAL image;
-    IFS(GetHGlobalFromStream(stream, &image));
-    if (SUCCEEDED(hr)) {
-      HANDLE std_output = GetStdHandle(STD_OUTPUT_HANDLE);
-      DWORD mode;
-      const BOOL update_mode = GetConsoleMode(std_output, &mode);
-      const void* const image_mem = GlobalLock(image);
-      DWORD bytes_written = 0;
-
-      // Clear output processing if necessary, then output the image.
-      if (update_mode) SetConsoleMode(std_output, 0);
-      if (!WriteFile(std_output, image_mem, (DWORD)GlobalSize(image),
-                     &bytes_written, NULL) ||
-          bytes_written != GlobalSize(image)) {
-        hr = E_FAIL;
-      }
-      if (update_mode) SetConsoleMode(std_output, mode);
-      GlobalUnlock(image);
-    }
-  }
-
-  if (frame != NULL) IUnknown_Release(frame);
-  if (encoder != NULL) IUnknown_Release(encoder);
-  if (factory != NULL) IUnknown_Release(factory);
-  if (stream != NULL) IUnknown_Release(stream);
-  return hr;
-}
-
-static int WritePNG(const char* out_file_name, int use_stdout,
-                    const WebPDecBuffer* const buffer) {
-  const uint32_t width = buffer->width;
-  const uint32_t height = buffer->height;
-  uint8_t* const rgb = buffer->u.RGBA.rgba;
-  const int stride = buffer->u.RGBA.stride;
-  const int has_alpha = (buffer->colorspace == MODE_BGRA);
-
-  return SUCCEEDED(WriteUsingWIC(out_file_name, use_stdout,
-                                 MAKE_REFGUID(GUID_ContainerFormatPng),
-                                 rgb, stride, width, height, has_alpha));
-}
-
-#elif defined(WEBP_HAVE_PNG)    // !HAVE_WINCODEC_H
-static void PNGAPI PNGErrorFunction(png_structp png, png_const_charp dummy) {
-  (void)dummy;  // remove variable-unused warning
-  longjmp(png_jmpbuf(png), 1);
-}
-
-static int WritePNG(FILE* out_file, const WebPDecBuffer* const buffer) {
-  const uint32_t width = buffer->width;
-  const uint32_t height = buffer->height;
-  uint8_t* const rgb = buffer->u.RGBA.rgba;
-  const int stride = buffer->u.RGBA.stride;
-  const int has_alpha = (buffer->colorspace == MODE_RGBA);
-  png_structp png;
-  png_infop info;
-  png_uint_32 y;
-
-  png = png_create_write_struct(PNG_LIBPNG_VER_STRING,
-                                NULL, PNGErrorFunction, NULL);
-  if (png == NULL) {
-    return 0;
-  }
-  info = png_create_info_struct(png);
-  if (info == NULL) {
-    png_destroy_write_struct(&png, NULL);
-    return 0;
-  }
-  if (setjmp(png_jmpbuf(png))) {
-    png_destroy_write_struct(&png, &info);
-    return 0;
-  }
-  png_init_io(png, out_file);
-  png_set_IHDR(png, info, width, height, 8,
-               has_alpha ? PNG_COLOR_TYPE_RGBA : PNG_COLOR_TYPE_RGB,
-               PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
-               PNG_FILTER_TYPE_DEFAULT);
-  png_write_info(png, info);
-  for (y = 0; y < height; ++y) {
-    png_bytep row = rgb + y * stride;
-    png_write_rows(png, &row, 1);
-  }
-  png_write_end(png, info);
-  png_destroy_write_struct(&png, &info);
-  return 1;
-}
-#else    // !HAVE_WINCODEC_H && !WEBP_HAVE_PNG
-static int WritePNG(FILE* out_file, const WebPDecBuffer* const buffer) {
-  (void)out_file;
-  (void)buffer;
-  fprintf(stderr, "PNG support not compiled. Please install the libpng "
-          "development package before building.\n");
-  fprintf(stderr, "You can run with -ppm flag to decode in PPM format.\n");
-  return 0;
-}
-#endif
-
-static int WritePPM(FILE* fout, const WebPDecBuffer* const buffer, int alpha) {
-  const uint32_t width = buffer->width;
-  const uint32_t height = buffer->height;
-  const uint8_t* const rgb = buffer->u.RGBA.rgba;
-  const int stride = buffer->u.RGBA.stride;
-  const size_t bytes_per_px = alpha ? 4 : 3;
-  uint32_t y;
-
-  if (alpha) {
-    fprintf(fout, "P7\nWIDTH %d\nHEIGHT %d\nDEPTH 4\nMAXVAL 255\n"
-                  "TUPLTYPE RGB_ALPHA\nENDHDR\n", width, height);
-  } else {
-    fprintf(fout, "P6\n%d %d\n255\n", width, height);
-  }
-  for (y = 0; y < height; ++y) {
-    if (fwrite(rgb + y * stride, width, bytes_per_px, fout) != bytes_per_px) {
-      return 0;
-    }
-  }
-  return 1;
-}
-
-static void PutLE16(uint8_t* const dst, uint32_t value) {
-  dst[0] = (value >> 0) & 0xff;
-  dst[1] = (value >> 8) & 0xff;
-}
-
-static void PutLE32(uint8_t* const dst, uint32_t value) {
-  PutLE16(dst + 0, (value >>  0) & 0xffff);
-  PutLE16(dst + 2, (value >> 16) & 0xffff);
-}
-
-#define BMP_HEADER_SIZE 54
-static int WriteBMP(FILE* fout, const WebPDecBuffer* const buffer) {
-  const int has_alpha = (buffer->colorspace != MODE_BGR);
-  const uint32_t width = buffer->width;
-  const uint32_t height = buffer->height;
-  const uint8_t* const rgba = buffer->u.RGBA.rgba;
-  const int stride = buffer->u.RGBA.stride;
-  const uint32_t bytes_per_px = has_alpha ? 4 : 3;
-  uint32_t y;
-  const uint32_t line_size = bytes_per_px * width;
-  const uint32_t bmp_stride = (line_size + 3) & ~3;   // pad to 4
-  const uint32_t total_size = bmp_stride * height + BMP_HEADER_SIZE;
-  uint8_t bmp_header[BMP_HEADER_SIZE] = { 0 };
-
-  // bitmap file header
-  PutLE16(bmp_header + 0, 0x4d42);                // signature 'BM'
-  PutLE32(bmp_header + 2, total_size);            // size including header
-  PutLE32(bmp_header + 6, 0);                     // reserved
-  PutLE32(bmp_header + 10, BMP_HEADER_SIZE);      // offset to pixel array
-  // bitmap info header
-  PutLE32(bmp_header + 14, 40);                   // DIB header size
-  PutLE32(bmp_header + 18, width);                // dimensions
-  PutLE32(bmp_header + 22, -(int)height);         // vertical flip!
-  PutLE16(bmp_header + 26, 1);                    // number of planes
-  PutLE16(bmp_header + 28, bytes_per_px * 8);     // bits per pixel
-  PutLE32(bmp_header + 30, 0);                    // no compression (BI_RGB)
-  PutLE32(bmp_header + 34, 0);                    // image size (dummy)
-  PutLE32(bmp_header + 38, 2400);                 // x pixels/meter
-  PutLE32(bmp_header + 42, 2400);                 // y pixels/meter
-  PutLE32(bmp_header + 46, 0);                    // number of palette colors
-  PutLE32(bmp_header + 50, 0);                    // important color count
-
-  // TODO(skal): color profile
-
-  // write header
-  if (fwrite(bmp_header, sizeof(bmp_header), 1, fout) != 1) {
-    return 0;
-  }
-
-  // write pixel array
-  for (y = 0; y < height; ++y) {
-    if (fwrite(rgba + y * stride, line_size, 1, fout) != 1) {
-      return 0;
-    }
-    // write padding zeroes
-    if (bmp_stride != line_size) {
-      const uint8_t zeroes[3] = { 0 };
-      if (fwrite(zeroes, bmp_stride - line_size, 1, fout) != 1) {
-        return 0;
-      }
-    }
-  }
-  return 1;
-}
-#undef BMP_HEADER_SIZE
-
-#define NUM_IFD_ENTRIES 15
-#define EXTRA_DATA_SIZE 16
-// 10b for signature/header + n * 12b entries + 4b for IFD terminator:
-#define EXTRA_DATA_OFFSET (10 + 12 * NUM_IFD_ENTRIES + 4)
-#define TIFF_HEADER_SIZE (EXTRA_DATA_OFFSET + EXTRA_DATA_SIZE)
-
-static int WriteTIFF(FILE* fout, const WebPDecBuffer* const buffer) {
-  const int has_alpha = (buffer->colorspace != MODE_RGB);
-  const uint32_t width = buffer->width;
-  const uint32_t height = buffer->height;
-  const uint8_t* const rgba = buffer->u.RGBA.rgba;
-  const int stride = buffer->u.RGBA.stride;
-  const uint8_t bytes_per_px = has_alpha ? 4 : 3;
-  // For non-alpha case, we omit tag 0x152 (ExtraSamples).
-  const uint8_t num_ifd_entries = has_alpha ? NUM_IFD_ENTRIES
-                                            : NUM_IFD_ENTRIES - 1;
-  uint8_t tiff_header[TIFF_HEADER_SIZE] = {
-    0x49, 0x49, 0x2a, 0x00,   // little endian signature
-    8, 0, 0, 0,               // offset to the unique IFD that follows
-    // IFD (offset = 8). Entries must be written in increasing tag order.
-    num_ifd_entries, 0,       // Number of entries in the IFD (12 bytes each).
-    0x00, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0,    //  10: Width  (TBD)
-    0x01, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0,    //  22: Height (TBD)
-    0x02, 0x01, 3, 0, bytes_per_px, 0, 0, 0,     //  34: BitsPerSample: 8888
-        EXTRA_DATA_OFFSET + 0, 0, 0, 0,
-    0x03, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0,    //  46: Compression: none
-    0x06, 0x01, 3, 0, 1, 0, 0, 0, 2, 0, 0, 0,    //  58: Photometric: RGB
-    0x11, 0x01, 4, 0, 1, 0, 0, 0,                //  70: Strips offset:
-        TIFF_HEADER_SIZE, 0, 0, 0,               //      data follows header
-    0x12, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0,    //  82: Orientation: topleft
-    0x15, 0x01, 3, 0, 1, 0, 0, 0,                //  94: SamplesPerPixels
-        bytes_per_px, 0, 0, 0,
-    0x16, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0,    // 106: Rows per strip (TBD)
-    0x17, 0x01, 4, 0, 1, 0, 0, 0, 0, 0, 0, 0,    // 118: StripByteCount (TBD)
-    0x1a, 0x01, 5, 0, 1, 0, 0, 0,                // 130: X-resolution
-        EXTRA_DATA_OFFSET + 8, 0, 0, 0,
-    0x1b, 0x01, 5, 0, 1, 0, 0, 0,                // 142: Y-resolution
-        EXTRA_DATA_OFFSET + 8, 0, 0, 0,
-    0x1c, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0,    // 154: PlanarConfiguration
-    0x28, 0x01, 3, 0, 1, 0, 0, 0, 2, 0, 0, 0,    // 166: ResolutionUnit (inch)
-    0x52, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0,    // 178: ExtraSamples: rgbA
-    0, 0, 0, 0,                                  // 190: IFD terminator
-    // EXTRA_DATA_OFFSET:
-    8, 0, 8, 0, 8, 0, 8, 0,      // BitsPerSample
-    72, 0, 0, 0, 1, 0, 0, 0      // 72 pixels/inch, for X/Y-resolution
-  };
-  uint32_t y;
-
-  // Fill placeholders in IFD:
-  PutLE32(tiff_header + 10 + 8, width);
-  PutLE32(tiff_header + 22 + 8, height);
-  PutLE32(tiff_header + 106 + 8, height);
-  PutLE32(tiff_header + 118 + 8, width * bytes_per_px * height);
-  if (!has_alpha) PutLE32(tiff_header + 178, 0);  // IFD terminator
-
-  // write header
-  if (fwrite(tiff_header, sizeof(tiff_header), 1, fout) != 1) {
-    return 0;
-  }
-  // write pixel values
-  for (y = 0; y < height; ++y) {
-    if (fwrite(rgba + y * stride, bytes_per_px, width, fout) != width) {
-      return 0;
-    }
-  }
-
-  return 1;
-}
-
-#undef TIFF_HEADER_SIZE
-#undef EXTRA_DATA_OFFSET
-#undef EXTRA_DATA_SIZE
-#undef NUM_IFD_ENTRIES
-
-static int WriteAlphaPlane(FILE* fout, const WebPDecBuffer* const buffer) {
-  const uint32_t width = buffer->width;
-  const uint32_t height = buffer->height;
-  const uint8_t* const a = buffer->u.YUVA.a;
-  const int a_stride = buffer->u.YUVA.a_stride;
-  uint32_t y;
-  assert(a != NULL);
-  fprintf(fout, "P5\n%d %d\n255\n", width, height);
-  for (y = 0; y < height; ++y) {
-    if (fwrite(a + y * a_stride, width, 1, fout) != 1) {
-      return 0;
-    }
-  }
-  return 1;
-}
-
-// format=PGM: save a grayscale PGM file using the IMC4 layout
-// (http://www.fourcc.org/yuv.php#IMC4). This is a very convenient format for
-// viewing the samples, esp. for odd dimensions.
-// format=YUV: just save the Y/U/V/A planes sequentially without header.
-static int WritePGMOrYUV(FILE* fout, const WebPDecBuffer* const buffer,
-                         OutputFileFormat format) {
-  const int width = buffer->width;
-  const int height = buffer->height;
-  const WebPYUVABuffer* const yuv = &buffer->u.YUVA;
-  int ok = 1;
-  int y;
-  const int pad = (format == YUV) ? 0 : 1;
-  const int uv_width = (width + 1) / 2;
-  const int uv_height = (height + 1) / 2;
-  const int out_stride = (width + pad) & ~pad;
-  const int a_height = yuv->a ? height : 0;
-  if (format == PGM) {
-    fprintf(fout, "P5\n%d %d\n255\n",
-            out_stride, height + uv_height + a_height);
-  }
-  for (y = 0; ok && y < height; ++y) {
-    ok &= (fwrite(yuv->y + y * yuv->y_stride, width, 1, fout) == 1);
-    if (format == PGM) {
-      if (width & 1) fputc(0, fout);    // padding byte
-    }
-  }
-  if (format == PGM) {   // IMC4 layout
-    for (y = 0; ok && y < uv_height; ++y) {
-      ok &= (fwrite(yuv->u + y * yuv->u_stride, uv_width, 1, fout) == 1);
-      ok &= (fwrite(yuv->v + y * yuv->v_stride, uv_width, 1, fout) == 1);
-    }
-  } else {
-    for (y = 0; ok && y < uv_height; ++y) {
-      ok &= (fwrite(yuv->u + y * yuv->u_stride, uv_width, 1, fout) == 1);
-    }
-    for (y = 0; ok && y < uv_height; ++y) {
-      ok &= (fwrite(yuv->v + y * yuv->v_stride, uv_width, 1, fout) == 1);
-    }
-  }
-  for (y = 0; ok && y < a_height; ++y) {
-    ok &= (fwrite(yuv->a + y * yuv->a_stride, width, 1, fout) == 1);
-    if (format == PGM) {
-      if (width & 1) fputc(0, fout);    // padding byte
-    }
-  }
-  return ok;
-}
 
 static int SaveOutput(const WebPDecBuffer* const buffer,
-                      OutputFileFormat format, const char* const out_file) {
-  FILE* fout = NULL;
-  int needs_open_file = 1;
-  const int use_stdout = !strcmp(out_file, "-");
+                      WebPOutputFileFormat format, const char* const out_file) {
+  const int use_stdout = (out_file != NULL) && !WSTRCMP(out_file, "-");
   int ok = 1;
   Stopwatch stop_watch;
 
   if (verbose) {
     StopwatchReset(&stop_watch);
   }
+  ok = WebPSaveImage(buffer, format, out_file);
 
-#ifdef HAVE_WINCODEC_H
-  needs_open_file = (format != PNG);
-#endif
-
-#if defined(_WIN32)
-  if (use_stdout && _setmode(_fileno(stdout), _O_BINARY) == -1) {
-    fprintf(stderr, "Failed to reopen stdout in O_BINARY mode.\n");
-    return -1;
-  }
-#endif
-
-  if (needs_open_file) {
-    fout = use_stdout ? stdout : fopen(out_file, "wb");
-    if (fout == NULL) {
-      fprintf(stderr, "Error opening output file %s\n", out_file);
-      return 0;
-    }
-  }
-
-  if (format == PNG) {
-#ifdef HAVE_WINCODEC_H
-    ok &= WritePNG(out_file, use_stdout, buffer);
-#else
-    ok &= WritePNG(fout, buffer);
-#endif
-  } else if (format == PAM) {
-    ok &= WritePPM(fout, buffer, 1);
-  } else if (format == PPM) {
-    ok &= WritePPM(fout, buffer, 0);
-  } else if (format == BMP) {
-    ok &= WriteBMP(fout, buffer);
-  } else if (format == TIFF) {
-    ok &= WriteTIFF(fout, buffer);
-  } else if (format == PGM || format == YUV) {
-    ok &= WritePGMOrYUV(fout, buffer, format);
-  } else if (format == ALPHA_PLANE_ONLY) {
-    ok &= WriteAlphaPlane(fout, buffer);
-  }
-  if (fout != NULL && fout != stdout) {
-    fclose(fout);
-  }
   if (ok) {
-    if (use_stdout) {
-      fprintf(stderr, "Saved to stdout\n");
-    } else {
-      fprintf(stderr, "Saved file %s\n", out_file);
+    if (!quiet) {
+      if (use_stdout) {
+        fprintf(stderr, "Saved to stdout\n");
+      } else {
+        WFPRINTF(stderr, "Saved file %s\n", (const W_CHAR*)out_file);
+      }
     }
     if (verbose) {
       const double write_time = StopwatchReadAndReset(&stop_watch);
@@ -533,7 +68,7 @@ static int SaveOutput(const WebPDecBuffer* const buffer,
     if (use_stdout) {
       fprintf(stderr, "Error writing to stdout !!\n");
     } else {
-      fprintf(stderr, "Error writing file %s !!\n", out_file);
+      WFPRINTF(stderr, "Error writing file %s !!\n", (const W_CHAR*)out_file);
     }
   }
   return ok;
@@ -541,7 +76,8 @@ static int SaveOutput(const WebPDecBuffer* const buffer,
 
 static void Help(void) {
   printf("Usage: dwebp in_file [options] [-o out_file]\n\n"
-         "Decodes the WebP image file to PNG format [Default]\n"
+         "Decodes the WebP image file to PNG format [Default].\n"
+         "Note: Animated WebP files are not supported.\n\n"
          "Use following options to convert into alternate image formats:\n"
          "  -pam ......... save the raw RGBA samples as a color PAM\n"
          "  -ppm ......... save the raw RGB samples as a color PPM\n"
@@ -552,56 +88,125 @@ static void Help(void) {
          "  -yuv ......... save the raw YUV samples in flat layout\n"
          "\n"
          " Other options are:\n"
-         "  -version  .... print version number and exit.\n"
-         "  -nofancy ..... don't use the fancy YUV420 upscaler.\n"
-         "  -nofilter .... disable in-loop filtering.\n"
-         "  -nodither .... disable dithering.\n"
+         "  -version ..... print version number and exit\n"
+         "  -nofancy ..... don't use the fancy YUV420 upscaler\n"
+         "  -nofilter .... disable in-loop filtering\n"
+         "  -nodither .... disable dithering\n"
          "  -dither <d> .. dithering strength (in 0..100)\n"
+         "  -alpha_dither  use alpha-plane dithering if needed\n"
          "  -mt .......... use multi-threading\n"
          "  -crop <x> <y> <w> <h> ... crop output with the given rectangle\n"
-         "  -scale <w> <h> .......... scale the output (*after* any cropping)\n"
-         "  -alpha ....... only save the alpha plane.\n"
+         "  -resize <w> <h> ......... resize output (*after* any cropping)\n"
+         "  -flip ........ flip the output vertically\n"
+         "  -alpha ....... only save the alpha plane\n"
          "  -incremental . use incremental decoding (useful for tests)\n"
-         "  -h     ....... this help message.\n"
-         "  -v     ....... verbose (e.g. print encoding/decoding times)\n"
+         "  -h ........... this help message\n"
+         "  -v ........... verbose (e.g. print encoding/decoding times)\n"
+         "  -quiet ....... quiet mode, don't print anything\n"
 #ifndef WEBP_DLL
-         "  -noasm ....... disable all assembly optimizations.\n"
+         "  -noasm ....... disable all assembly optimizations\n"
 #endif
         );
 }
 
-static const char* const kStatusMessages[] = {
-  "OK", "OUT_OF_MEMORY", "INVALID_PARAM", "BITSTREAM_ERROR",
-  "UNSUPPORTED_FEATURE", "SUSPENDED", "USER_ABORT", "NOT_ENOUGH_DATA"
-};
-
 static const char* const kFormatType[] = {
   "unspecified", "lossy", "lossless"
 };
 
-int main(int argc, const char *argv[]) {
+static uint8_t* AllocateExternalBuffer(WebPDecoderConfig* config,
+                                       WebPOutputFileFormat format,
+                                       int use_external_memory) {
+  uint8_t* external_buffer = NULL;
+  WebPDecBuffer* const output_buffer = &config->output;
+  int w = config->input.width;
+  int h = config->input.height;
+  if (config->options.use_scaling) {
+    w = config->options.scaled_width;
+    h = config->options.scaled_height;
+  } else if (config->options.use_cropping) {
+    w = config->options.crop_width;
+    h = config->options.crop_height;
+  }
+  if (format >= RGB && format <= rgbA_4444) {
+    const int bpp = (format == RGB || format == BGR) ? 3
+                  : (format == RGBA_4444 || format == rgbA_4444 ||
+                     format == RGB_565) ? 2
+                  : 4;
+    uint32_t stride = bpp * w + 7;   // <- just for exercising
+    external_buffer = (uint8_t*)WebPMalloc(stride * h);
+    if (external_buffer == NULL) return NULL;
+    output_buffer->u.RGBA.stride = stride;
+    output_buffer->u.RGBA.size = stride * h;
+    output_buffer->u.RGBA.rgba = external_buffer;
+  } else {    // YUV and YUVA
+    const int has_alpha = WebPIsAlphaMode(output_buffer->colorspace);
+    uint8_t* tmp;
+    uint32_t stride = w + 3;
+    uint32_t uv_stride = (w + 1) / 2 + 13;
+    uint32_t total_size = stride * h * (has_alpha ? 2 : 1)
+                        + 2 * uv_stride * (h + 1) / 2;
+    assert(format >= YUV && format <= YUVA);
+    external_buffer = (uint8_t*)WebPMalloc(total_size);
+    if (external_buffer == NULL) return NULL;
+    tmp = external_buffer;
+    output_buffer->u.YUVA.y = tmp;
+    output_buffer->u.YUVA.y_stride = stride;
+    output_buffer->u.YUVA.y_size = stride * h;
+    tmp += output_buffer->u.YUVA.y_size;
+    if (has_alpha) {
+      output_buffer->u.YUVA.a = tmp;
+      output_buffer->u.YUVA.a_stride = stride;
+      output_buffer->u.YUVA.a_size = stride * h;
+      tmp += output_buffer->u.YUVA.a_size;
+    } else {
+      output_buffer->u.YUVA.a = NULL;
+      output_buffer->u.YUVA.a_stride = 0;
+    }
+    output_buffer->u.YUVA.u = tmp;
+    output_buffer->u.YUVA.u_stride = uv_stride;
+    output_buffer->u.YUVA.u_size = uv_stride * (h + 1) / 2;
+    tmp += output_buffer->u.YUVA.u_size;
+
+    output_buffer->u.YUVA.v = tmp;
+    output_buffer->u.YUVA.v_stride = uv_stride;
+    output_buffer->u.YUVA.v_size = uv_stride * (h + 1) / 2;
+    tmp += output_buffer->u.YUVA.v_size;
+    assert(tmp <= external_buffer + total_size);
+  }
+  output_buffer->is_external_memory = use_external_memory;
+  return external_buffer;
+}
+
+int main(int argc, const char* argv[]) {
   int ok = 0;
-  const char *in_file = NULL;
-  const char *out_file = NULL;
+  const char* in_file = NULL;
+  const char* out_file = NULL;
 
   WebPDecoderConfig config;
   WebPDecBuffer* const output_buffer = &config.output;
   WebPBitstreamFeatures* const bitstream = &config.input;
-  OutputFileFormat format = PNG;
+  WebPOutputFileFormat format = PNG;
+  uint8_t* external_buffer = NULL;
+  int use_external_memory = 0;
+  const uint8_t* data = NULL;
+
   int incremental = 0;
   int c;
 
+  INIT_WARGV(argc, argv);
+
   if (!WebPInitDecoderConfig(&config)) {
     fprintf(stderr, "Library version mismatch!\n");
-    return -1;
+    FREE_WARGV_AND_RETURN(-1);
   }
 
   for (c = 1; c < argc; ++c) {
+    int parse_error = 0;
     if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
       Help();
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else if (!strcmp(argv[c], "-o") && c < argc - 1) {
-      out_file = argv[++c];
+      out_file = (const char*)GET_WARGV(argv, ++c);
     } else if (!strcmp(argv[c], "-alpha")) {
       format = ALPHA_PLANE_ONLY;
     } else if (!strcmp(argv[c], "-nofancy")) {
@@ -616,31 +221,64 @@ int main(int argc, const char *argv[]) {
       format = BMP;
     } else if (!strcmp(argv[c], "-tiff")) {
       format = TIFF;
+    } else if (!strcmp(argv[c], "-quiet")) {
+      quiet = 1;
     } else if (!strcmp(argv[c], "-version")) {
       const int version = WebPGetDecoderVersion();
       printf("%d.%d.%d\n",
              (version >> 16) & 0xff, (version >> 8) & 0xff, version & 0xff);
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else if (!strcmp(argv[c], "-pgm")) {
       format = PGM;
     } else if (!strcmp(argv[c], "-yuv")) {
-      format = YUV;
+      format = RAW_YUV;
+    } else if (!strcmp(argv[c], "-pixel_format") && c < argc - 1) {
+      const char* const fmt = argv[++c];
+      if      (!strcmp(fmt, "RGB"))  format = RGB;
+      else if (!strcmp(fmt, "RGBA")) format = RGBA;
+      else if (!strcmp(fmt, "BGR"))  format = BGR;
+      else if (!strcmp(fmt, "BGRA")) format = BGRA;
+      else if (!strcmp(fmt, "ARGB")) format = ARGB;
+      else if (!strcmp(fmt, "RGBA_4444")) format = RGBA_4444;
+      else if (!strcmp(fmt, "RGB_565")) format = RGB_565;
+      else if (!strcmp(fmt, "rgbA")) format = rgbA;
+      else if (!strcmp(fmt, "bgrA")) format = bgrA;
+      else if (!strcmp(fmt, "Argb")) format = Argb;
+      else if (!strcmp(fmt, "rgbA_4444")) format = rgbA_4444;
+      else if (!strcmp(fmt, "YUV"))  format = YUV;
+      else if (!strcmp(fmt, "YUVA")) format = YUVA;
+      else {
+        fprintf(stderr, "Can't parse pixel_format %s\n", fmt);
+        parse_error = 1;
+      }
+    } else if (!strcmp(argv[c], "-external_memory") && c < argc - 1) {
+      use_external_memory = ExUtilGetInt(argv[++c], 0, &parse_error);
+      parse_error |= (use_external_memory > 2 || use_external_memory < 0);
+      if (parse_error) {
+        fprintf(stderr, "Can't parse 'external_memory' value %s\n", argv[c]);
+      }
     } else if (!strcmp(argv[c], "-mt")) {
       config.options.use_threads = 1;
+    } else if (!strcmp(argv[c], "-alpha_dither")) {
+      config.options.alpha_dithering_strength = 100;
     } else if (!strcmp(argv[c], "-nodither")) {
       config.options.dithering_strength = 0;
     } else if (!strcmp(argv[c], "-dither") && c < argc - 1) {
-      config.options.dithering_strength = strtol(argv[++c], NULL, 0);
+      config.options.dithering_strength =
+          ExUtilGetInt(argv[++c], 0, &parse_error);
     } else if (!strcmp(argv[c], "-crop") && c < argc - 4) {
       config.options.use_cropping = 1;
-      config.options.crop_left   = strtol(argv[++c], NULL, 0);
-      config.options.crop_top    = strtol(argv[++c], NULL, 0);
-      config.options.crop_width  = strtol(argv[++c], NULL, 0);
-      config.options.crop_height = strtol(argv[++c], NULL, 0);
-    } else if (!strcmp(argv[c], "-scale") && c < argc - 2) {
+      config.options.crop_left   = ExUtilGetInt(argv[++c], 0, &parse_error);
+      config.options.crop_top    = ExUtilGetInt(argv[++c], 0, &parse_error);
+      config.options.crop_width  = ExUtilGetInt(argv[++c], 0, &parse_error);
+      config.options.crop_height = ExUtilGetInt(argv[++c], 0, &parse_error);
+    } else if ((!strcmp(argv[c], "-scale") || !strcmp(argv[c], "-resize")) &&
+               c < argc - 2) {  // '-scale' is left for compatibility
       config.options.use_scaling = 1;
-      config.options.scaled_width  = strtol(argv[++c], NULL, 0);
-      config.options.scaled_height = strtol(argv[++c], NULL, 0);
+      config.options.scaled_width  = ExUtilGetInt(argv[++c], 0, &parse_error);
+      config.options.scaled_height = ExUtilGetInt(argv[++c], 0, &parse_error);
+    } else if (!strcmp(argv[c], "-flip")) {
+      config.options.flip = 1;
     } else if (!strcmp(argv[c], "-v")) {
       verbose = 1;
 #ifndef WEBP_DLL
@@ -650,45 +288,35 @@ int main(int argc, const char *argv[]) {
     } else if (!strcmp(argv[c], "-incremental")) {
       incremental = 1;
     } else if (!strcmp(argv[c], "--")) {
-      if (c < argc - 1) in_file = argv[++c];
+      if (c < argc - 1) in_file = (const char*)GET_WARGV(argv, ++c);
       break;
     } else if (argv[c][0] == '-') {
       fprintf(stderr, "Unknown option '%s'\n", argv[c]);
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(-1);
     } else {
-      in_file = argv[c];
+      in_file = (const char*)GET_WARGV(argv, c);
+    }
+
+    if (parse_error) {
+      Help();
+      FREE_WARGV_AND_RETURN(-1);
     }
   }
 
   if (in_file == NULL) {
     fprintf(stderr, "missing input file!!\n");
     Help();
-    return -1;
+    FREE_WARGV_AND_RETURN(-1);
   }
 
+  if (quiet) verbose = 0;
+
   {
-    Stopwatch stop_watch;
     VP8StatusCode status = VP8_STATUS_OK;
     size_t data_size = 0;
-    const uint8_t* data = NULL;
-
-    if (!ExUtilReadFile(in_file, &data, &data_size)) return -1;
-
-    if (verbose) {
-      StopwatchReset(&stop_watch);
-    }
-
-    status = WebPGetFeatures(data, data_size, bitstream);
-    if (status != VP8_STATUS_OK) {
-      goto end;
-    }
-
-    if (bitstream->has_animation) {
-      fprintf(stderr,
-              "Error! Decoding of an animated WebP file is not supported.\n"
-              "       Use webpmux to extract the individual frames or\n"
-              "       vwebp to view this image.\n");
+    if (!LoadWebP(in_file, &data, &data_size, bitstream)) {
+      FREE_WARGV_AND_RETURN(-1);
     }
 
     switch (format) {
@@ -708,70 +336,86 @@ int main(int argc, const char *argv[]) {
       case BMP:
         output_buffer->colorspace = bitstream->has_alpha ? MODE_BGRA : MODE_BGR;
         break;
-      case TIFF:    // note: force pre-multiplied alpha
-        output_buffer->colorspace =
-            bitstream->has_alpha ? MODE_rgbA : MODE_RGB;
+      case TIFF:
+        output_buffer->colorspace = bitstream->has_alpha ? MODE_RGBA : MODE_RGB;
         break;
       case PGM:
-      case YUV:
+      case RAW_YUV:
         output_buffer->colorspace = bitstream->has_alpha ? MODE_YUVA : MODE_YUV;
         break;
       case ALPHA_PLANE_ONLY:
         output_buffer->colorspace = MODE_YUVA;
         break;
-      default:
-        free((void*)data);
-        return -1;
+      // forced modes:
+      case RGB: output_buffer->colorspace = MODE_RGB; break;
+      case RGBA: output_buffer->colorspace = MODE_RGBA; break;
+      case BGR: output_buffer->colorspace = MODE_BGR; break;
+      case BGRA: output_buffer->colorspace = MODE_BGRA; break;
+      case ARGB: output_buffer->colorspace = MODE_ARGB; break;
+      case RGBA_4444: output_buffer->colorspace = MODE_RGBA_4444; break;
+      case RGB_565: output_buffer->colorspace = MODE_RGB_565; break;
+      case rgbA: output_buffer->colorspace = MODE_rgbA; break;
+      case bgrA: output_buffer->colorspace = MODE_bgrA; break;
+      case Argb: output_buffer->colorspace = MODE_Argb; break;
+      case rgbA_4444: output_buffer->colorspace = MODE_rgbA_4444; break;
+      case YUV: output_buffer->colorspace = MODE_YUV; break;
+      case YUVA: output_buffer->colorspace = MODE_YUVA; break;
+      default: goto Exit;
     }
 
-    // Decoding call.
-    if (!incremental) {
-      status = WebPDecode(data, data_size, &config);
-    } else {
-      WebPIDecoder* const idec = WebPIDecode(data, data_size, &config);
-      if (idec == NULL) {
-        fprintf(stderr, "Failed during WebPINewDecoder().\n");
-        status = VP8_STATUS_OUT_OF_MEMORY;
-        goto end;
+    if (use_external_memory > 0 && format >= RGB) {
+      external_buffer = AllocateExternalBuffer(&config, format,
+                                               use_external_memory);
+      if (external_buffer == NULL) goto Exit;
+    }
+
+    {
+      Stopwatch stop_watch;
+      if (verbose) StopwatchReset(&stop_watch);
+
+      if (incremental) {
+        status = DecodeWebPIncremental(data, data_size, &config);
       } else {
-        status = WebPIUpdate(idec, data, data_size);
-        WebPIDelete(idec);
+        status = DecodeWebP(data, data_size, &config);
+      }
+      if (verbose) {
+        const double decode_time = StopwatchReadAndReset(&stop_watch);
+        fprintf(stderr, "Time to decode picture: %.3fs\n", decode_time);
       }
     }
 
-    if (verbose) {
-      const double decode_time = StopwatchReadAndReset(&stop_watch);
-      fprintf(stderr, "Time to decode picture: %.3fs\n", decode_time);
-    }
- end:
-    free((void*)data);
     ok = (status == VP8_STATUS_OK);
     if (!ok) {
-      fprintf(stderr, "Decoding of %s failed.\n", in_file);
-      fprintf(stderr, "Status: %d (%s)\n", status, kStatusMessages[status]);
+      PrintWebPError(in_file, status);
       goto Exit;
     }
   }
 
   if (out_file != NULL) {
-    fprintf(stderr, "Decoded %s. Dimensions: %d x %d %s. Format: %s. "
-                    "Now saving...\n",
-            in_file, output_buffer->width, output_buffer->height,
-            bitstream->has_alpha ? " (with alpha)" : "",
-            kFormatType[bitstream->format]);
+    if (!quiet) {
+      WFPRINTF(stderr, "Decoded %s.", (const W_CHAR*)in_file);
+      fprintf(stderr, " Dimensions: %d x %d %s. Format: %s. Now saving...\n",
+              output_buffer->width, output_buffer->height,
+              bitstream->has_alpha ? " (with alpha)" : "",
+              kFormatType[bitstream->format]);
+    }
     ok = SaveOutput(output_buffer, format, out_file);
   } else {
-    fprintf(stderr, "File %s can be decoded "
-                    "(dimensions: %d x %d %s. Format: %s).\n",
-            in_file, output_buffer->width, output_buffer->height,
-            bitstream->has_alpha ? " (with alpha)" : "",
-            kFormatType[bitstream->format]);
-    fprintf(stderr, "Nothing written; "
-                    "use -o flag to save the result as e.g. PNG.\n");
+    if (!quiet) {
+      WFPRINTF(stderr, "File %s can be decoded ", (const W_CHAR*)in_file);
+      fprintf(stderr, "(dimensions: %d x %d %s. Format: %s).\n",
+              output_buffer->width, output_buffer->height,
+              bitstream->has_alpha ? " (with alpha)" : "",
+              kFormatType[bitstream->format]);
+      fprintf(stderr, "Nothing written; "
+                      "use -o flag to save the result as e.g. PNG.\n");
+    }
   }
  Exit:
   WebPFreeDecBuffer(output_buffer);
-  return ok ? 0 : -1;
+  WebPFree((void*)external_buffer);
+  WebPFree((void*)data);
+  FREE_WARGV_AND_RETURN(ok ? 0 : -1);
 }
 
 //------------------------------------------------------------------------------

examples/example_util.c

@@ -11,62 +11,129 @@
 //
 
 #include "./example_util.h"
+
+#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
-// -----------------------------------------------------------------------------
-// File I/O
+#include "webp/mux_types.h"
+#include "../imageio/imageio_util.h"
 
-int ExUtilReadFile(const char* const file_name,
-                   const uint8_t** data, size_t* data_size) {
-  int ok;
-  void* file_data;
-  size_t file_size;
-  FILE* in;
+//------------------------------------------------------------------------------
+// String parsing
 
-  if (file_name == NULL || data == NULL || data_size == NULL) return 0;
-  *data = NULL;
-  *data_size = 0;
-
-  in = fopen(file_name, "rb");
-  if (in == NULL) {
-    fprintf(stderr, "cannot open input file '%s'\n", file_name);
-    return 0;
+uint32_t ExUtilGetUInt(const char* const v, int base, int* const error) {
+  char* end = NULL;
+  const uint32_t n = (v != NULL) ? (uint32_t)strtoul(v, &end, base) : 0u;
+  if (end == v && error != NULL && !*error) {
+    *error = 1;
+    fprintf(stderr, "Error! '%s' is not an integer.\n",
+            (v != NULL) ? v : "(null)");
   }
-  fseek(in, 0, SEEK_END);
-  file_size = ftell(in);
-  fseek(in, 0, SEEK_SET);
-  file_data = malloc(file_size);
-  if (file_data == NULL) return 0;
-  ok = (fread(file_data, file_size, 1, in) == 1);
-  fclose(in);
+  return n;
+}
 
-  if (!ok) {
-    fprintf(stderr, "Could not read %d bytes of data from file %s\n",
-            (int)file_size, file_name);
-    free(file_data);
-    return 0;
+int ExUtilGetInt(const char* const v, int base, int* const error) {
+  return (int)ExUtilGetUInt(v, base, error);
+}
+
+int ExUtilGetInts(const char* v, int base, int max_output, int output[]) {
+  int n, error = 0;
+  for (n = 0; v != NULL && n < max_output; ++n) {
+    const int value = ExUtilGetInt(v, base, &error);
+    if (error) return -1;
+    output[n] = value;
+    v = strchr(v, ',');
+    if (v != NULL) ++v;   // skip over the trailing ','
+  }
+  return n;
+}
+
+float ExUtilGetFloat(const char* const v, int* const error) {
+  char* end = NULL;
+  const float f = (v != NULL) ? (float)strtod(v, &end) : 0.f;
+  if (end == v && error != NULL && !*error) {
+    *error = 1;
+    fprintf(stderr, "Error! '%s' is not a floating point number.\n",
+            (v != NULL) ? v : "(null)");
+  }
+  return f;
+}
+
+//------------------------------------------------------------------------------
+
+static void ResetCommandLineArguments(int argc, const char* argv[],
+                                      CommandLineArguments* const args) {
+  assert(args != NULL);
+  args->argc_ = argc;
+  args->argv_ = argv;
+  args->own_argv_ = 0;
+  WebPDataInit(&args->argv_data_);
+}
+
+void ExUtilDeleteCommandLineArguments(CommandLineArguments* const args) {
+  if (args != NULL) {
+    if (args->own_argv_) {
+      WebPFree((void*)args->argv_);
+      WebPDataClear(&args->argv_data_);
+    }
+    ResetCommandLineArguments(0, NULL, args);
+  }
+}
+
+#define MAX_ARGC 16384
+int ExUtilInitCommandLineArguments(int argc, const char* argv[],
+                                   CommandLineArguments* const args) {
+  if (args == NULL || argv == NULL) return 0;
+  ResetCommandLineArguments(argc, argv, args);
+  if (argc == 1 && argv[0][0] != '-') {
+    char* cur;
+    const char sep[] = " \t\r\n\f\v";
+
+#if defined(_WIN32) && defined(_UNICODE)
+    fprintf(stderr,
+            "Error: Reading arguments from a file is a feature unavailable "
+            "with Unicode binaries.\n");
+    return 0;
+#endif
+
+    if (!ExUtilReadFileToWebPData(argv[0], &args->argv_data_)) {
+      return 0;
+    }
+    args->own_argv_ = 1;
+    args->argv_ = (const char**)WebPMalloc(MAX_ARGC * sizeof(*args->argv_));
+    if (args->argv_ == NULL) {
+      ExUtilDeleteCommandLineArguments(args);
+      return 0;
+    }
+
+    argc = 0;
+    for (cur = strtok((char*)args->argv_data_.bytes, sep);
+         cur != NULL;
+         cur = strtok(NULL, sep)) {
+      if (argc == MAX_ARGC) {
+        fprintf(stderr, "ERROR: Arguments limit %d reached\n", MAX_ARGC);
+        ExUtilDeleteCommandLineArguments(args);
+        return 0;
+      }
+      assert(strlen(cur) != 0);
+      args->argv_[argc++] = cur;
+    }
+    args->argc_ = argc;
   }
-  *data = (uint8_t*)file_data;
-  *data_size = file_size;
   return 1;
 }
 
-int ExUtilWriteFile(const char* const file_name,
-                    const uint8_t* data, size_t data_size) {
-  int ok;
-  FILE* out;
+//------------------------------------------------------------------------------
 
-  if (file_name == NULL || data == NULL) {
-    return 0;
-  }
-  out = fopen(file_name, "wb");
-  if (out == NULL) {
-    fprintf(stderr, "Error! Cannot open output file '%s'\n", file_name);
-    return 0;
-  }
-  ok = (fwrite(data, data_size, 1, out) == 1);
-  fclose(out);
-  return ok;
+int ExUtilReadFileToWebPData(const char* const filename,
+                             WebPData* const webp_data) {
+  const uint8_t* data;
+  size_t size;
+  if (webp_data == NULL) return 0;
+  if (!ImgIoUtilReadFile(filename, &data, &size)) return 0;
+  webp_data->bytes = data;
+  webp_data->size = size;
+  return 1;
 }
-

examples/example_util.h

@@ -14,20 +14,54 @@
 #define WEBP_EXAMPLES_EXAMPLE_UTIL_H_
 
 #include "webp/types.h"
+#include "webp/mux_types.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
-// Allocates storage for entire file 'file_name' and returns contents and size
-// in 'data' and 'data_size'. Returns 1 on success, 0 otherwise. '*data' should
-// be deleted using free().
-int ExUtilReadFile(const char* const file_name,
-                   const uint8_t** data, size_t* data_size);
+//------------------------------------------------------------------------------
+// String parsing
 
-// Write a data segment into a file named 'file_name'. Returns true if ok.
-int ExUtilWriteFile(const char* const file_name,
-                    const uint8_t* data, size_t data_size);
+// Parses 'v' using strto(ul|l|d)(). If error is non-NULL, '*error' is set to
+// true on failure while on success it is left unmodified to allow chaining of
+// calls. An error is only printed on the first occurrence.
+uint32_t ExUtilGetUInt(const char* const v, int base, int* const error);
+int ExUtilGetInt(const char* const v, int base, int* const error);
+float ExUtilGetFloat(const char* const v, int* const error);
+
+// This variant of ExUtilGetInt() will parse multiple integers from a
+// comma-separated list. Up to 'max_output' integers are parsed.
+// The result is placed in the output[] array, and the number of integers
+// actually parsed is returned, or -1 if an error occurred.
+int ExUtilGetInts(const char* v, int base, int max_output, int output[]);
+
+// Reads a file named 'filename' into a WebPData structure. The content of
+// webp_data is overwritten. Returns false in case of error.
+int ExUtilReadFileToWebPData(const char* const filename,
+                             WebPData* const webp_data);
+
+//------------------------------------------------------------------------------
+// Command-line arguments
+
+typedef struct {
+  int argc_;
+  const char** argv_;
+  WebPData argv_data_;
+  int own_argv_;
+} CommandLineArguments;
+
+// Initializes the structure from the command-line parameters. If there is
+// only one parameter and it does not start with a '-', then it is assumed to
+// be a file name. This file will be read and tokenized into command-line
+// arguments. The content of 'args' is overwritten.
+// Returns false in case of error (memory allocation failure, non
+// existing file, too many arguments, ...).
+int ExUtilInitCommandLineArguments(int argc, const char* argv[],
+                                   CommandLineArguments* const args);
+
+// Deallocate all memory and reset 'args'.
+void ExUtilDeleteCommandLineArguments(CommandLineArguments* const args);
 
 #ifdef __cplusplus
 }    // extern "C"

examples/gif2webp.c

@@ -14,187 +14,37 @@
 
 #include <assert.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include "webp/config.h"
 #endif
 
 #ifdef WEBP_HAVE_GIF
 
+#if defined(HAVE_UNISTD_H) && HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
 #include <gif_lib.h>
 #include "webp/encode.h"
 #include "webp/mux.h"
-#include "./example_util.h"
-#include "./gif2webp_util.h"
+#include "../examples/example_util.h"
+#include "../imageio/imageio_util.h"
+#include "./gifdec.h"
+#include "./unicode.h"
+#include "./unicode_gif.h"
 
-#define GIF_TRANSPARENT_MASK 0x01
-#define GIF_DISPOSE_MASK     0x07
-#define GIF_DISPOSE_SHIFT    2
-#define WHITE_COLOR          0xffffffff
-#define MAX_CACHE_SIZE       30
+#if !defined(STDIN_FILENO)
+#define STDIN_FILENO 0
+#endif
 
 //------------------------------------------------------------------------------
 
-static int transparent_index = -1;  // Index of transparent color in the map.
+static int transparent_index = GIF_INDEX_INVALID;  // Opaque by default.
 
-static void SanitizeKeyFrameIntervals(size_t* const kmin_ptr,
-                                      size_t* const kmax_ptr) {
-  size_t kmin = *kmin_ptr;
-  size_t kmax = *kmax_ptr;
-  int print_warning = 1;
-
-  if (kmin == 0) {  // Disable keyframe insertion.
-    kmax = ~0;
-    kmin = kmax - 1;
-    print_warning = 0;
-  }
-  if (kmax == 0) {
-    kmax = ~0;
-    print_warning = 0;
-  }
-
-  if (kmin >= kmax) {
-    kmin = kmax - 1;
-    if (print_warning) {
-      fprintf(stderr,
-              "WARNING: Setting kmin = %d, so that kmin < kmax.\n", (int)kmin);
-    }
-  } else if (kmin < (kmax / 2 + 1)) {
-    // This ensures that cache.keyframe + kmin >= kmax is always true. So, we
-    // can flush all the frames in the ‘count_since_key_frame == kmax’ case.
-    kmin = (kmax / 2 + 1);
-    if (print_warning) {
-      fprintf(stderr,
-              "WARNING: Setting kmin = %d, so that kmin >= kmax / 2 + 1.\n",
-              (int)kmin);
-    }
-  }
-  // Limit the max number of frames that are allocated.
-  if (kmax - kmin > MAX_CACHE_SIZE) {
-    kmin = kmax - MAX_CACHE_SIZE;
-    if (print_warning) {
-      fprintf(stderr,
-              "WARNING: Setting kmin = %d, so that kmax - kmin <= 30.\n",
-              (int)kmin);
-    }
-  }
-  *kmin_ptr = kmin;
-  *kmax_ptr = kmax;
-}
-
-static void Remap(const uint8_t* const src, const GifFileType* const gif,
-                  uint32_t* dst, int len) {
-  int i;
-  const GifColorType* colors;
-  const ColorMapObject* const cmap =
-      gif->Image.ColorMap ? gif->Image.ColorMap : gif->SColorMap;
-  if (cmap == NULL) return;
-  colors = cmap->Colors;
-
-  for (i = 0; i < len; ++i) {
-    const GifColorType c = colors[src[i]];
-    dst[i] = (src[i] == transparent_index) ? WEBP_UTIL_TRANSPARENT_COLOR
-           : c.Blue | (c.Green << 8) | (c.Red << 16) | (0xff << 24);
-  }
-}
-
-// Read the GIF image frame.
-static int ReadFrame(GifFileType* const gif, WebPFrameRect* const gif_rect,
-                     WebPPicture* const webp_frame) {
-  WebPPicture sub_image;
-  const GifImageDesc image_desc = gif->Image;
-  uint32_t* dst = NULL;
-  uint8_t* tmp = NULL;
-  int ok = 0;
-  WebPFrameRect rect = {
-      image_desc.Left, image_desc.Top, image_desc.Width, image_desc.Height
-  };
-  *gif_rect = rect;
-
-  // Use a view for the sub-picture:
-  if (!WebPPictureView(webp_frame, rect.x_offset, rect.y_offset,
-                       rect.width, rect.height, &sub_image)) {
-    fprintf(stderr, "Sub-image %dx%d at position %d,%d is invalid!\n",
-            rect.width, rect.height, rect.x_offset, rect.y_offset);
-    return 0;
-  }
-  dst = sub_image.argb;
-
-  tmp = (uint8_t*)malloc(rect.width * sizeof(*tmp));
-  if (tmp == NULL) goto End;
-
-  if (image_desc.Interlace) {  // Interlaced image.
-    // We need 4 passes, with the following offsets and jumps.
-    const int interlace_offsets[] = { 0, 4, 2, 1 };
-    const int interlace_jumps[]   = { 8, 8, 4, 2 };
-    int pass;
-    for (pass = 0; pass < 4; ++pass) {
-      int y;
-      for (y = interlace_offsets[pass]; y < rect.height;
-           y += interlace_jumps[pass]) {
-        if (DGifGetLine(gif, tmp, rect.width) == GIF_ERROR) goto End;
-        Remap(tmp, gif, dst + y * sub_image.argb_stride, rect.width);
-      }
-    }
-  } else {  // Non-interlaced image.
-    int y;
-    for (y = 0; y < rect.height; ++y) {
-      if (DGifGetLine(gif, tmp, rect.width) == GIF_ERROR) goto End;
-      Remap(tmp, gif, dst + y * sub_image.argb_stride, rect.width);
-    }
-  }
-  ok = 1;
-
- End:
-  if (!ok) webp_frame->error_code = sub_image.error_code;
-  WebPPictureFree(&sub_image);
-  free(tmp);
-  return ok;
-}
-
-static int GetBackgroundColor(const ColorMapObject* const color_map,
-                              int bgcolor_idx, uint32_t* const bgcolor) {
-  if (transparent_index != -1 && bgcolor_idx == transparent_index) {
-    *bgcolor = WEBP_UTIL_TRANSPARENT_COLOR;  // Special case.
-    return 1;
-  } else if (color_map == NULL || color_map->Colors == NULL
-             || bgcolor_idx >= color_map->ColorCount) {
-    return 0;  // Invalid color map or index.
-  } else {
-    const GifColorType color = color_map->Colors[bgcolor_idx];
-    *bgcolor = (0xff        << 24)
-             | (color.Red   << 16)
-             | (color.Green <<  8)
-             | (color.Blue  <<  0);
-    return 1;
-  }
-}
-
-static void DisplayGifError(const GifFileType* const gif, int gif_error) {
-  // GIFLIB_MAJOR is only defined in libgif >= 4.2.0.
-  // libgif 4.2.0 has retired PrintGifError() and added GifErrorString().
-#if defined(GIFLIB_MAJOR) && defined(GIFLIB_MINOR) && \
-        ((GIFLIB_MAJOR == 4 && GIFLIB_MINOR >= 2) || GIFLIB_MAJOR > 4)
-#if GIFLIB_MAJOR >= 5
-  // Static string actually, hence the const char* cast.
-  const char* error_str = (const char*)GifErrorString(
-      (gif == NULL) ? gif_error : gif->Error);
-#else
-  const char* error_str = (const char*)GifErrorString();
-  (void)gif;
-#endif
-  if (error_str == NULL) error_str = "Unknown error";
-  fprintf(stderr, "GIFLib Error %d: %s\n", gif_error, error_str);
-#else
-  (void)gif;
-  fprintf(stderr, "GIFLib Error %d: ", gif_error);
-  PrintGifError();
-  fprintf(stderr, "\n");
-#endif
-}
-
-static const char* const kErrorMessages[] = {
+static const char* const kErrorMessages[-WEBP_MUX_NOT_ENOUGH_DATA + 1] = {
   "WEBP_MUX_NOT_FOUND", "WEBP_MUX_INVALID_ARGUMENT", "WEBP_MUX_BAD_DATA",
   "WEBP_MUX_MEMORY_ERROR", "WEBP_MUX_NOT_ENOUGH_DATA"
 };
@@ -215,101 +65,122 @@ enum {
 static void Help(void) {
   printf("Usage:\n");
   printf(" gif2webp [options] gif_file -o webp_file\n");
-  printf("options:\n");
-  printf("  -h / -help  ............ this help\n");
-  printf("  -lossy ................. Encode image using lossy compression.\n");
-  printf("  -mixed ................. For each frame in the image, pick lossy\n"
-         "                           or lossless compression heuristically.\n");
+  printf("Options:\n");
+  printf("  -h / -help ............. this help\n");
+  printf("  -lossy ................. encode image using lossy compression\n");
+  printf("  -mixed ................. for each frame in the image, pick lossy\n"
+         "                           or lossless compression heuristically\n");
   printf("  -q <float> ............. quality factor (0:small..100:big)\n");
   printf("  -m <int> ............... compression method (0=fast, 6=slowest)\n");
-  printf("  -kmin <int> ............ Min distance between key frames\n");
-  printf("  -kmax <int> ............ Max distance between key frames\n");
+  printf("  -min_size .............. minimize output size (default:off)\n"
+         "                           lossless compression by default; can be\n"
+         "                           combined with -q, -m, -lossy or -mixed\n"
+         "                           options\n");
+  printf("  -kmin <int> ............ min distance between key frames\n");
+  printf("  -kmax <int> ............ max distance between key frames\n");
   printf("  -f <int> ............... filter strength (0=off..100)\n");
   printf("  -metadata <string> ..... comma separated list of metadata to\n");
   printf("                           ");
-  printf("copy from the input to the output if present.\n");
-  printf("                           "
-         "Valid values: all, none, icc, xmp (default)\n");
+  printf("copy from the input to the output if present\n");
+  printf("                           ");
+  printf("Valid values: all, none, icc, xmp (default)\n");
+  printf("  -loop_compatibility .... use compatibility mode for Chrome\n");
+  printf("                           version prior to M62 (inclusive)\n");
   printf("  -mt .................... use multi-threading if available\n");
   printf("\n");
-  printf("  -version ............... print version number and exit.\n");
-  printf("  -v ..................... verbose.\n");
-  printf("  -quiet ................. don't print anything.\n");
+  printf("  -version ............... print version number and exit\n");
+  printf("  -v ..................... verbose\n");
+  printf("  -quiet ................. don't print anything\n");
   printf("\n");
 }
 
 //------------------------------------------------------------------------------
 
-int main(int argc, const char *argv[]) {
+int main(int argc, const char* argv[]) {
   int verbose = 0;
   int gif_error = GIF_ERROR;
   WebPMuxError err = WEBP_MUX_OK;
   int ok = 0;
-  const char *in_file = NULL, *out_file = NULL;
-  FILE* out = NULL;
+  const W_CHAR* in_file = NULL, *out_file = NULL;
   GifFileType* gif = NULL;
-  WebPConfig config;
-  WebPPicture frame;
-  WebPMuxFrameInfo info;
-  WebPMuxAnimParams anim = { WHITE_COLOR, 0 };
-  WebPFrameCache* cache = NULL;
+  int frame_duration = 0;
+  int frame_timestamp = 0;
+  GIFDisposeMethod orig_dispose = GIF_DISPOSE_NONE;
 
-  int is_first_frame = 1;     // Whether we are processing the first frame.
+  WebPPicture frame;                // Frame rectangle only (not disposed).
+  WebPPicture curr_canvas;          // Not disposed.
+  WebPPicture prev_canvas;          // Disposed.
+
+  WebPAnimEncoder* enc = NULL;
+  WebPAnimEncoderOptions enc_options;
+  WebPConfig config;
+
+  int frame_number = 0;     // Whether we are processing the first frame.
   int done;
   int c;
   int quiet = 0;
-  WebPMux* mux = NULL;
-  WebPData webp_data = { NULL, 0 };
+  WebPData webp_data;
+
   int keep_metadata = METADATA_XMP;  // ICC not output by default.
-  int stored_icc = 0;  // Whether we have already stored an ICC profile.
-  int stored_xmp = 0;
+  WebPData icc_data;
+  int stored_icc = 0;         // Whether we have already stored an ICC profile.
+  WebPData xmp_data;
+  int stored_xmp = 0;         // Whether we have already stored an XMP profile.
+  int loop_count = 0;         // default: infinite
+  int stored_loop_count = 0;  // Whether we have found an explicit loop count.
+  int loop_compatibility = 0;
+  WebPMux* mux = NULL;
 
   int default_kmin = 1;  // Whether to use default kmin value.
   int default_kmax = 1;
-  size_t kmin = 0;
-  size_t kmax = 0;
-  int allow_mixed = 0;   // If true, each frame can be lossy or lossless.
 
-  memset(&info, 0, sizeof(info));
-  info.id = WEBP_CHUNK_ANMF;
-  info.dispose_method = WEBP_MUX_DISPOSE_BACKGROUND;
-  info.blend_method = WEBP_MUX_BLEND;
+  INIT_WARGV(argc, argv);
 
-  if (!WebPConfigInit(&config) || !WebPPictureInit(&frame)) {
+  if (!WebPConfigInit(&config) || !WebPAnimEncoderOptionsInit(&enc_options) ||
+      !WebPPictureInit(&frame) || !WebPPictureInit(&curr_canvas) ||
+      !WebPPictureInit(&prev_canvas)) {
     fprintf(stderr, "Error! Version mismatch!\n");
-    return -1;
+    FREE_WARGV_AND_RETURN(-1);
   }
   config.lossless = 1;  // Use lossless compression by default.
-  config.image_hint = WEBP_HINT_GRAPH;   // always low-color
+
+  WebPDataInit(&webp_data);
+  WebPDataInit(&icc_data);
+  WebPDataInit(&xmp_data);
 
   if (argc == 1) {
     Help();
-    return 0;
+    FREE_WARGV_AND_RETURN(0);
   }
 
   for (c = 1; c < argc; ++c) {
+    int parse_error = 0;
     if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
       Help();
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else if (!strcmp(argv[c], "-o") && c < argc - 1) {
-      out_file = argv[++c];
+      out_file = GET_WARGV(argv, ++c);
     } else if (!strcmp(argv[c], "-lossy")) {
       config.lossless = 0;
     } else if (!strcmp(argv[c], "-mixed")) {
-      allow_mixed = 1;
+      enc_options.allow_mixed = 1;
       config.lossless = 0;
+    } else if (!strcmp(argv[c], "-loop_compatibility")) {
+      loop_compatibility = 1;
     } else if (!strcmp(argv[c], "-q") && c < argc - 1) {
-      config.quality = (float)strtod(argv[++c], NULL);
+      config.quality = ExUtilGetFloat(argv[++c], &parse_error);
     } else if (!strcmp(argv[c], "-m") && c < argc - 1) {
-      config.method = strtol(argv[++c], NULL, 0);
+      config.method = ExUtilGetInt(argv[++c], 0, &parse_error);
+    } else if (!strcmp(argv[c], "-min_size")) {
+      enc_options.minimize_size = 1;
     } else if (!strcmp(argv[c], "-kmax") && c < argc - 1) {
-      kmax = strtoul(argv[++c], NULL, 0);
+      enc_options.kmax = ExUtilGetInt(argv[++c], 0, &parse_error);
       default_kmax = 0;
     } else if (!strcmp(argv[c], "-kmin") && c < argc - 1) {
-      kmin = strtoul(argv[++c], NULL, 0);
+      enc_options.kmin = ExUtilGetInt(argv[++c], 0, &parse_error);
       default_kmin = 0;
     } else if (!strcmp(argv[c], "-f") && c < argc - 1) {
-      config.filter_strength = strtol(argv[++c], NULL, 0);
+      config.filter_strength = ExUtilGetInt(argv[++c], 0, &parse_error);
     } else if (!strcmp(argv[c], "-metadata") && c < argc - 1) {
       static const struct {
         const char* option;
@@ -345,7 +216,7 @@ int main(int argc, const char *argv[]) {
           fprintf(stderr, "Error! Unknown metadata type '%.*s'\n",
                   (int)(token - start), start);
           Help();
-          return -1;
+          FREE_WARGV_AND_RETURN(-1);
         }
         start = token + 1;
       }
@@ -358,31 +229,37 @@ int main(int argc, const char *argv[]) {
              (enc_version >> 16) & 0xff, (enc_version >> 8) & 0xff,
              enc_version & 0xff, (mux_version >> 16) & 0xff,
              (mux_version >> 8) & 0xff, mux_version & 0xff);
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else if (!strcmp(argv[c], "-quiet")) {
       quiet = 1;
+      enc_options.verbose = 0;
     } else if (!strcmp(argv[c], "-v")) {
       verbose = 1;
+      enc_options.verbose = 1;
     } else if (!strcmp(argv[c], "--")) {
-      if (c < argc - 1) in_file = argv[++c];
+      if (c < argc - 1) in_file = GET_WARGV(argv, ++c);
       break;
     } else if (argv[c][0] == '-') {
       fprintf(stderr, "Error! Unknown option '%s'\n", argv[c]);
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(-1);
     } else {
-      in_file = argv[c];
+      in_file = GET_WARGV(argv, c);
+    }
+
+    if (parse_error) {
+      Help();
+      FREE_WARGV_AND_RETURN(-1);
     }
   }
 
   // Appropriate default kmin, kmax values for lossy and lossless.
   if (default_kmin) {
-    kmin = config.lossless ? 9 : 3;
+    enc_options.kmin = config.lossless ? 9 : 3;
   }
   if (default_kmax) {
-    kmax = config.lossless ? 17 : 5;
+    enc_options.kmax = config.lossless ? 17 : 5;
   }
-  SanitizeKeyFrameIntervals(&kmin, &kmax);
 
   if (!WebPValidateConfig(&config)) {
     fprintf(stderr, "Error! Invalid configuration.\n");
@@ -396,30 +273,9 @@ int main(int argc, const char *argv[]) {
   }
 
   // Start the decoder object
-#if defined(GIFLIB_MAJOR) && (GIFLIB_MAJOR >= 5)
-  // There was an API change in version 5.0.0.
-  gif = DGifOpenFileName(in_file, &gif_error);
-#else
-  gif = DGifOpenFileName(in_file);
-#endif
+  gif = DGifOpenFileUnicode(in_file, &gif_error);
   if (gif == NULL) goto End;
 
-  // Allocate current buffer
-  frame.width = gif->SWidth;
-  frame.height = gif->SHeight;
-  frame.use_argb = 1;
-  if (!WebPPictureAlloc(&frame)) goto End;
-
-  // Initialize cache
-  cache = WebPFrameCacheNew(frame.width, frame.height, kmin, kmax, allow_mixed);
-  if (cache == NULL) goto End;
-
-  mux = WebPMuxNew();
-  if (mux == NULL) {
-    fprintf(stderr, "ERROR: could not create a mux object.\n");
-    goto End;
-  }
-
   // Loop over GIF images
   done = 0;
   do {
@@ -428,65 +284,118 @@ int main(int argc, const char *argv[]) {
 
     switch (type) {
       case IMAGE_DESC_RECORD_TYPE: {
-        WebPFrameRect gif_rect;
+        GIFFrameRect gif_rect;
+        GifImageDesc* const image_desc = &gif->Image;
 
         if (!DGifGetImageDesc(gif)) goto End;
-        if (!ReadFrame(gif, &gif_rect, &frame)) {
-          goto End;
+
+        if (frame_number == 0) {
+          if (verbose) {
+            printf("Canvas screen: %d x %d\n", gif->SWidth, gif->SHeight);
+          }
+          // Fix some broken GIF global headers that report
+          // 0 x 0 screen dimension.
+          if (gif->SWidth == 0 || gif->SHeight == 0) {
+            image_desc->Left = 0;
+            image_desc->Top = 0;
+            gif->SWidth = image_desc->Width;
+            gif->SHeight = image_desc->Height;
+            if (gif->SWidth <= 0 || gif->SHeight <= 0) {
+              goto End;
+            }
+            if (verbose) {
+              printf("Fixed canvas screen dimension to: %d x %d\n",
+                     gif->SWidth, gif->SHeight);
+            }
+          }
+          // Allocate current buffer.
+          frame.width = gif->SWidth;
+          frame.height = gif->SHeight;
+          frame.use_argb = 1;
+          if (!WebPPictureAlloc(&frame)) goto End;
+          GIFClearPic(&frame, NULL);
+          if (!(WebPPictureCopy(&frame, &curr_canvas) &&
+                WebPPictureCopy(&frame, &prev_canvas))) {
+            fprintf(stderr, "Error allocating canvas.\n");
+            goto End;
+          }
+
+          // Background color.
+          GIFGetBackgroundColor(gif->SColorMap, gif->SBackGroundColor,
+                                transparent_index,
+                                &enc_options.anim_params.bgcolor);
+
+          // Initialize encoder.
+          enc = WebPAnimEncoderNew(curr_canvas.width, curr_canvas.height,
+                                   &enc_options);
+          if (enc == NULL) {
+            fprintf(stderr,
+                    "Error! Could not create encoder object. Possibly due to "
+                    "a memory error.\n");
+            goto End;
+          }
         }
 
-        if (!WebPFrameCacheAddFrame(cache, &config, &gif_rect, &frame, &info)) {
-          fprintf(stderr, "Error! Cannot encode frame as WebP\n");
-          fprintf(stderr, "Error code: %d\n", frame.error_code);
+        // Some even more broken GIF can have sub-rect with zero width/height.
+        if (image_desc->Width == 0 || image_desc->Height == 0) {
+          image_desc->Width = gif->SWidth;
+          image_desc->Height = gif->SHeight;
         }
 
-        err = WebPFrameCacheFlush(cache, verbose, mux);
-        if (err != WEBP_MUX_OK) {
-          fprintf(stderr, "ERROR (%s): Could not add animation frame.\n",
-                  ErrorString(err));
+        if (!GIFReadFrame(gif, transparent_index, &gif_rect, &frame)) {
           goto End;
         }
-        is_first_frame = 0;
+        // Blend frame rectangle with previous canvas to compose full canvas.
+        // Note that 'curr_canvas' is same as 'prev_canvas' at this point.
+        GIFBlendFrames(&frame, &gif_rect, &curr_canvas);
+
+        if (!WebPAnimEncoderAdd(enc, &curr_canvas, frame_timestamp, &config)) {
+          fprintf(stderr, "Error while adding frame #%d: %s\n", frame_number,
+                  WebPAnimEncoderGetError(enc));
+          goto End;
+        } else {
+          ++frame_number;
+        }
+
+        // Update canvases.
+        GIFDisposeFrame(orig_dispose, &gif_rect, &prev_canvas, &curr_canvas);
+        GIFCopyPixels(&curr_canvas, &prev_canvas);
+
+        // Force frames with a small or no duration to 100ms to be consistent
+        // with web browsers and other transcoding tools. This also avoids
+        // incorrect durations between frames when padding frames are
+        // discarded.
+        if (frame_duration <= 10) {
+          frame_duration = 100;
+        }
+
+        // Update timestamp (for next frame).
+        frame_timestamp += frame_duration;
+
+        // In GIF, graphic control extensions are optional for a frame, so we
+        // may not get one before reading the next frame. To handle this case,
+        // we reset frame properties to reasonable defaults for the next frame.
+        orig_dispose = GIF_DISPOSE_NONE;
+        frame_duration = 0;
+        transparent_index = GIF_INDEX_INVALID;
         break;
       }
       case EXTENSION_RECORD_TYPE: {
         int extension;
-        GifByteType *data = NULL;
+        GifByteType* data = NULL;
         if (DGifGetExtension(gif, &extension, &data) == GIF_ERROR) {
           goto End;
         }
+        if (data == NULL) continue;
+
         switch (extension) {
           case COMMENT_EXT_FUNC_CODE: {
             break;  // Do nothing for now.
           }
           case GRAPHICS_EXT_FUNC_CODE: {
-            const int flags = data[1];
-            const int dispose = (flags >> GIF_DISPOSE_SHIFT) & GIF_DISPOSE_MASK;
-            const int delay = data[2] | (data[3] << 8);  // In 10 ms units.
-            if (data[0] != 4) goto End;
-            info.duration = delay * 10;  // Duration is in 1 ms units for WebP.
-            if (dispose == 3) {
-              static int warning_printed = 0;
-              if (!warning_printed) {
-                fprintf(stderr, "WARNING: GIF_DISPOSE_RESTORE unsupported.\n");
-                warning_printed = 1;
-              }
-              // failsafe. TODO(urvang): emulate the correct behaviour by
-              // recoding the whole frame.
-              info.dispose_method = WEBP_MUX_DISPOSE_BACKGROUND;
-            } else {
-              info.dispose_method =
-                  (dispose == 2) ? WEBP_MUX_DISPOSE_BACKGROUND
-                                 : WEBP_MUX_DISPOSE_NONE;
-            }
-            transparent_index = (flags & GIF_TRANSPARENT_MASK) ? data[4] : -1;
-            if (is_first_frame) {
-              if (!GetBackgroundColor(gif->SColorMap, gif->SBackGroundColor,
-                                      &anim.bgcolor)) {
-                fprintf(stderr, "GIF decode warning: invalid background color "
-                                "index. Assuming white background.\n");
-              }
-              WebPUtilClearPic(&frame, NULL);
+            if (!GIFReadGraphicsExtension(data, &frame_duration, &orig_dispose,
+                                          &transparent_index)) {
+              goto End;
             }
             break;
           }
@@ -495,13 +404,15 @@ int main(int argc, const char *argv[]) {
           }
           case APPLICATION_EXT_FUNC_CODE: {
             if (data[0] != 11) break;    // Chunk is too short
-            if (!memcmp(data + 1, "NETSCAPE2.0", 11)) {
-              // Recognize and parse Netscape2.0 NAB extension for loop count.
-              if (DGifGetExtensionNext(gif, &data) == GIF_ERROR) goto End;
-              if (data == NULL) goto End;  // Loop count sub-block missing.
-              if (data[0] != 3 && data[1] != 1) break;   // wrong size/marker
-              anim.loop_count = data[2] | (data[3] << 8);
-              if (verbose) printf("Loop count: %d\n", anim.loop_count);
+            if (!memcmp(data + 1, "NETSCAPE2.0", 11) ||
+                !memcmp(data + 1, "ANIMEXTS1.0", 11)) {
+              if (!GIFReadLoopCount(gif, &data, &loop_count)) {
+                goto End;
+              }
+              if (verbose) {
+                fprintf(stderr, "Loop count: %d\n", loop_count);
+              }
+              stored_loop_count = loop_compatibility ? (loop_count != 0) : 1;
             } else {  // An extension containing metadata.
               // We only store the first encountered chunk of each type, and
               // only if requested by the user.
@@ -512,55 +423,8 @@ int main(int argc, const char *argv[]) {
                                  !stored_icc &&
                                  !memcmp(data + 1, "ICCRGBG1012", 11);
               if (is_xmp || is_icc) {
-                const char* const fourccs[2] = { "XMP " , "ICCP" };
-                const char* const features[2] = { "XMP" , "ICC" };
-                WebPData metadata = { NULL, 0 };
-                // Construct metadata from sub-blocks.
-                // Usual case (including ICC profile): In each sub-block, the
-                // first byte specifies its size in bytes (0 to 255) and the
-                // rest of the bytes contain the data.
-                // Special case for XMP data: In each sub-block, the first byte
-                // is also part of the XMP payload. XMP in GIF also has a 257
-                // byte padding data. See the XMP specification for details.
-                while (1) {
-                  WebPData prev_metadata = metadata;
-                  WebPData subblock;
-                  if (DGifGetExtensionNext(gif, &data) == GIF_ERROR) {
-                    WebPDataClear(&metadata);
-                    goto End;
-                  }
-                  if (data == NULL) break;  // Finished.
-                  subblock.size = is_xmp ? data[0] + 1 : data[0];
-                  assert(subblock.size > 0);
-                  subblock.bytes = is_xmp ? data : data + 1;
-                  metadata.bytes =
-                      (uint8_t*)realloc((void*)metadata.bytes,
-                                        prev_metadata.size + subblock.size);
-                  if (metadata.bytes == NULL) {
-                    WebPDataClear(&prev_metadata);
-                    goto End;
-                  }
-                  metadata.size += subblock.size;
-                  memcpy((void*)(metadata.bytes + prev_metadata.size),
-                         subblock.bytes, subblock.size);
-                }
-                if (is_xmp) {
-                  // XMP padding data is 0x01, 0xff, 0xfe ... 0x01, 0x00.
-                  const size_t xmp_pading_size = 257;
-                  if (metadata.size > xmp_pading_size) {
-                    metadata.size -= xmp_pading_size;
-                  }
-                }
-
-                // Add metadata chunk.
-                err = WebPMuxSetChunk(mux, fourccs[is_icc], &metadata, 1);
-                if (verbose) {
-                  printf("%s size: %d\n", features[is_icc], (int)metadata.size);
-                }
-                WebPDataClear(&metadata);
-                if (err != WEBP_MUX_OK) {
-                  fprintf(stderr, "ERROR (%s): Could not set %s chunk.\n",
-                          ErrorString(err), features[is_icc]);
+                if (!GIFReadMetadata(gif, &data,
+                                     is_xmp ? &xmp_data : &icc_data)) {
                   goto End;
                 }
                 if (is_icc) {
@@ -594,38 +458,113 @@ int main(int argc, const char *argv[]) {
     }
   } while (!done);
 
-  // Flush any pending frames.
-  err = WebPFrameCacheFlushAll(cache, verbose, mux);
-  if (err != WEBP_MUX_OK) {
-    fprintf(stderr, "ERROR (%s): Could not add animation frame.\n",
-            ErrorString(err));
-    goto End;
+  // Last NULL frame.
+  if (!WebPAnimEncoderAdd(enc, NULL, frame_timestamp, NULL)) {
+    fprintf(stderr, "Error flushing WebP muxer.\n");
+    fprintf(stderr, "%s\n", WebPAnimEncoderGetError(enc));
   }
 
-  // Finish muxing
-  err = WebPMuxSetAnimationParams(mux, &anim);
-  if (err != WEBP_MUX_OK) {
-    fprintf(stderr, "ERROR (%s): Could not set animation parameters.\n",
-            ErrorString(err));
+  if (!WebPAnimEncoderAssemble(enc, &webp_data)) {
+    fprintf(stderr, "%s\n", WebPAnimEncoderGetError(enc));
     goto End;
   }
+  // If there's only one frame, we don't need to handle loop count.
+  if (frame_number == 1) {
+    loop_count = 0;
+  } else if (!loop_compatibility) {
+    if (!stored_loop_count) {
+      // if no loop-count element is seen, the default is '1' (loop-once)
+      // and we need to signal it explicitly in WebP. Note however that
+      // in case there's a single frame, we still don't need to store it.
+      if (frame_number > 1) {
+        stored_loop_count = 1;
+        loop_count = 1;
+      }
+    } else if (loop_count > 0 && loop_count < 65535) {
+      // adapt GIF's semantic to WebP's (except in the infinite-loop case)
+      loop_count += 1;
+    }
+  }
+  // loop_count of 0 is the default (infinite), so no need to signal it
+  if (loop_count == 0) stored_loop_count = 0;
+
+  if (stored_loop_count || stored_icc || stored_xmp) {
+    // Re-mux to add loop count and/or metadata as needed.
+    mux = WebPMuxCreate(&webp_data, 1);
+    if (mux == NULL) {
+      fprintf(stderr, "ERROR: Could not re-mux to add loop count/metadata.\n");
+      goto End;
+    }
+    WebPDataClear(&webp_data);
+
+    if (stored_loop_count) {  // Update loop count.
+      WebPMuxAnimParams new_params;
+      err = WebPMuxGetAnimationParams(mux, &new_params);
+      if (err != WEBP_MUX_OK) {
+        fprintf(stderr, "ERROR (%s): Could not fetch loop count.\n",
+                ErrorString(err));
+        goto End;
+      }
+      new_params.loop_count = loop_count;
+      err = WebPMuxSetAnimationParams(mux, &new_params);
+      if (err != WEBP_MUX_OK) {
+        fprintf(stderr, "ERROR (%s): Could not update loop count.\n",
+                ErrorString(err));
+        goto End;
+      }
+    }
+
+    if (stored_icc) {   // Add ICCP chunk.
+      err = WebPMuxSetChunk(mux, "ICCP", &icc_data, 1);
+      if (verbose) {
+        fprintf(stderr, "ICC size: %d\n", (int)icc_data.size);
+      }
+      if (err != WEBP_MUX_OK) {
+        fprintf(stderr, "ERROR (%s): Could not set ICC chunk.\n",
+                ErrorString(err));
+        goto End;
+      }
+    }
+
+    if (stored_xmp) {   // Add XMP chunk.
+      err = WebPMuxSetChunk(mux, "XMP ", &xmp_data, 1);
+      if (verbose) {
+        fprintf(stderr, "XMP size: %d\n", (int)xmp_data.size);
+      }
+      if (err != WEBP_MUX_OK) {
+        fprintf(stderr, "ERROR (%s): Could not set XMP chunk.\n",
+                ErrorString(err));
+        goto End;
+      }
+    }
+
+    err = WebPMuxAssemble(mux, &webp_data);
+    if (err != WEBP_MUX_OK) {
+      fprintf(stderr, "ERROR (%s): Could not assemble when re-muxing to add "
+              "loop count/metadata.\n", ErrorString(err));
+      goto End;
+    }
+  }
 
-  err = WebPMuxAssemble(mux, &webp_data);
-  if (err != WEBP_MUX_OK) {
-    fprintf(stderr, "ERROR (%s) assembling the WebP file.\n", ErrorString(err));
-    goto End;
-  }
   if (out_file != NULL) {
-    if (!ExUtilWriteFile(out_file, webp_data.bytes, webp_data.size)) {
-      fprintf(stderr, "Error writing output file: %s\n", out_file);
+    if (!ImgIoUtilWriteFile((const char*)out_file, webp_data.bytes,
+                            webp_data.size)) {
+      WFPRINTF(stderr, "Error writing output file: %s\n", out_file);
       goto End;
     }
     if (!quiet) {
-      printf("Saved output file: %s\n", out_file);
+      if (!WSTRCMP(out_file, "-")) {
+        fprintf(stderr, "Saved %d bytes to STDIO\n",
+                (int)webp_data.size);
+      } else {
+        WFPRINTF(stderr, "Saved output file (%d bytes): %s\n",
+                 (int)webp_data.size, out_file);
+      }
     }
   } else {
     if (!quiet) {
-      printf("Nothing written; use -o flag to save the result.\n");
+      fprintf(stderr, "Nothing written; use -o flag to save the result "
+                      "(%d bytes).\n", (int)webp_data.size);
     }
   }
 
@@ -634,25 +573,32 @@ int main(int argc, const char *argv[]) {
   gif_error = GIF_OK;
 
  End:
-  WebPDataClear(&webp_data);
+  WebPDataClear(&icc_data);
+  WebPDataClear(&xmp_data);
   WebPMuxDelete(mux);
+  WebPDataClear(&webp_data);
   WebPPictureFree(&frame);
-  WebPFrameCacheDelete(cache);
-  if (out != NULL && out_file != NULL) fclose(out);
+  WebPPictureFree(&curr_canvas);
+  WebPPictureFree(&prev_canvas);
+  WebPAnimEncoderDelete(enc);
 
   if (gif_error != GIF_OK) {
-    DisplayGifError(gif, gif_error);
+    GIFDisplayError(gif, gif_error);
   }
   if (gif != NULL) {
+#if LOCAL_GIF_PREREQ(5,1)
+    DGifCloseFile(gif, &gif_error);
+#else
     DGifCloseFile(gif);
+#endif
   }
 
-  return !ok;
+  FREE_WARGV_AND_RETURN(!ok);
 }
 
 #else  // !WEBP_HAVE_GIF
 
-int main(int argc, const char *argv[]) {
+int main(int argc, const char* argv[]) {
   fprintf(stderr, "GIF support not enabled in %s.\n", argv[0]);
   (void)argc;
   return 0;

examples/gif2webp_util.c

@@ -1,667 +0,0 @@
-// Copyright 2013 Google Inc. All Rights Reserved.
-//
-// Use of this source code is governed by a BSD-style license
-// that can be found in the COPYING file in the root of the source
-// tree. An additional intellectual property rights grant can be found
-// in the file PATENTS. All contributing project authors may
-// be found in the AUTHORS file in the root of the source tree.
-// -----------------------------------------------------------------------------
-//
-//  Helper structs and methods for gif2webp tool.
-//
-
-#include <assert.h>
-#include <stdio.h>
-
-#include "webp/encode.h"
-#include "./gif2webp_util.h"
-
-#define DELTA_INFINITY      1ULL << 32
-#define KEYFRAME_NONE       -1
-
-//------------------------------------------------------------------------------
-// Helper utilities.
-
-static void ClearRectangle(WebPPicture* const picture,
-                           int left, int top, int width, int height) {
-  int j;
-  for (j = top; j < top + height; ++j) {
-    uint32_t* const dst = picture->argb + j * picture->argb_stride;
-    int i;
-    for (i = left; i < left + width; ++i) {
-      dst[i] = WEBP_UTIL_TRANSPARENT_COLOR;
-    }
-  }
-}
-
-void WebPUtilClearPic(WebPPicture* const picture,
-                      const WebPFrameRect* const rect) {
-  if (rect != NULL) {
-    ClearRectangle(picture, rect->x_offset, rect->y_offset,
-                   rect->width, rect->height);
-  } else {
-    ClearRectangle(picture, 0, 0, picture->width, picture->height);
-  }
-}
-
-// TODO: Also used in picture.c. Move to a common location?
-// Copy width x height pixels from 'src' to 'dst' honoring the strides.
-static void CopyPlane(const uint8_t* src, int src_stride,
-                      uint8_t* dst, int dst_stride, int width, int height) {
-  while (height-- > 0) {
-    memcpy(dst, src, width);
-    src += src_stride;
-    dst += dst_stride;
-  }
-}
-
-// Copy pixels from 'src' to 'dst' honoring strides. 'src' and 'dst' are assumed
-// to be already allocated.
-static void CopyPixels(const WebPPicture* const src, WebPPicture* const dst) {
-  assert(src->width == dst->width && src->height == dst->height);
-  CopyPlane((uint8_t*)src->argb, 4 * src->argb_stride, (uint8_t*)dst->argb,
-            4 * dst->argb_stride, 4 * src->width, src->height);
-}
-
-// Given 'src' picture and its frame rectangle 'rect', blend it into 'dst'.
-static void BlendPixels(const WebPPicture* const src,
-                        const WebPFrameRect* const rect,
-                        WebPPicture* const dst) {
-  int j;
-  assert(src->width == dst->width && src->height == dst->height);
-  for (j = rect->y_offset; j < rect->y_offset + rect->height; ++j) {
-    int i;
-    for (i = rect->x_offset; i < rect->x_offset + rect->width; ++i) {
-      const uint32_t src_pixel = src->argb[j * src->argb_stride + i];
-      const int src_alpha = src_pixel >> 24;
-      if (src_alpha != 0) {
-        dst->argb[j * dst->argb_stride + i] = src_pixel;
-      }
-    }
-  }
-}
-
-// Replace transparent pixels within 'dst_rect' of 'dst' by those in the 'src'.
-static void ReduceTransparency(const WebPPicture* const src,
-                               const WebPFrameRect* const rect,
-                               WebPPicture* const dst) {
-  int i, j;
-  assert(src != NULL && dst != NULL && rect != NULL);
-  assert(src->width == dst->width && src->height == dst->height);
-  for (j = rect->y_offset; j < rect->y_offset + rect->height; ++j) {
-    for (i = rect->x_offset; i < rect->x_offset + rect->width; ++i) {
-      const uint32_t src_pixel = src->argb[j * src->argb_stride + i];
-      const int src_alpha = src_pixel >> 24;
-      const uint32_t dst_pixel = dst->argb[j * dst->argb_stride + i];
-      const int dst_alpha = dst_pixel >> 24;
-      if (dst_alpha == 0 && src_alpha == 0xff) {
-        dst->argb[j * dst->argb_stride + i] = src_pixel;
-      }
-    }
-  }
-}
-
-// Replace similar blocks of pixels by a 'see-through' transparent block
-// with uniform average color.
-static void FlattenSimilarBlocks(const WebPPicture* const src,
-                                 const WebPFrameRect* const rect,
-                                 WebPPicture* const dst) {
-  int i, j;
-  const int block_size = 8;
-  const int y_start = (rect->y_offset + block_size) & ~(block_size - 1);
-  const int y_end = (rect->y_offset + rect->height) & ~(block_size - 1);
-  const int x_start = (rect->x_offset + block_size) & ~(block_size - 1);
-  const int x_end = (rect->x_offset + rect->width) & ~(block_size - 1);
-  assert(src != NULL && dst != NULL && rect != NULL);
-  assert(src->width == dst->width && src->height == dst->height);
-  assert((block_size & (block_size - 1)) == 0);  // must be a power of 2
-  // Iterate over each block and count similar pixels.
-  for (j = y_start; j < y_end; j += block_size) {
-    for (i = x_start; i < x_end; i += block_size) {
-      int cnt = 0;
-      int avg_r = 0, avg_g = 0, avg_b = 0;
-      int x, y;
-      const uint32_t* const psrc = src->argb + j * src->argb_stride + i;
-      uint32_t* const pdst = dst->argb + j * dst->argb_stride + i;
-      for (y = 0; y < block_size; ++y) {
-        for (x = 0; x < block_size; ++x) {
-          const uint32_t src_pixel = psrc[x + y * src->argb_stride];
-          const int alpha = src_pixel >> 24;
-          if (alpha == 0xff &&
-              src_pixel == pdst[x + y * dst->argb_stride]) {
-              ++cnt;
-              avg_r += (src_pixel >> 16) & 0xff;
-              avg_g += (src_pixel >>  8) & 0xff;
-              avg_b += (src_pixel >>  0) & 0xff;
-          }
-        }
-      }
-      // If we have a fully similar block, we replace it with an
-      // average transparent block. This compresses better in lossy mode.
-      if (cnt == block_size * block_size) {
-        const uint32_t color = (0x00          << 24) |
-                               ((avg_r / cnt) << 16) |
-                               ((avg_g / cnt) <<  8) |
-                               ((avg_b / cnt) <<  0);
-        for (y = 0; y < block_size; ++y) {
-          for (x = 0; x < block_size; ++x) {
-            pdst[x + y * dst->argb_stride] = color;
-          }
-        }
-      }
-    }
-  }
-}
-
-//------------------------------------------------------------------------------
-// Key frame related utilities.
-
-// Returns true if 'curr' frame with frame rectangle 'curr_rect' is a key frame,
-// that is, it can be decoded independently of 'prev' canvas.
-static int IsKeyFrame(const WebPPicture* const curr,
-                      const WebPFrameRect* const curr_rect,
-                      const WebPPicture* const prev) {
-  int i, j;
-  int is_key_frame = 1;
-
-  // If previous canvas (with previous frame disposed) is all transparent,
-  // current frame is a key frame.
-  for (i = 0; i < prev->width; ++i) {
-    for (j = 0; j < prev->height; ++j) {
-      const uint32_t prev_alpha = (prev->argb[j * prev->argb_stride + i]) >> 24;
-      if (prev_alpha != 0) {
-        is_key_frame = 0;
-        break;
-      }
-    }
-    if (!is_key_frame) break;
-  }
-  if (is_key_frame) return 1;
-
-  // If current frame covers the whole canvas and does not contain any
-  // transparent pixels that depend on previous canvas, then current frame is
-  // a key frame.
-  if (curr_rect->width == curr->width && curr_rect->height == curr->height) {
-    assert(curr_rect->x_offset == 0 && curr_rect->y_offset == 0);
-    is_key_frame = 1;
-    for (j = 0; j < prev->height; ++j) {
-      for (i = 0; i < prev->width; ++i) {
-        const uint32_t prev_alpha =
-            (prev->argb[j * prev->argb_stride + i]) >> 24;
-        const uint32_t curr_alpha =
-            (curr->argb[j * curr->argb_stride + i]) >> 24;
-        if (curr_alpha != 0xff && prev_alpha != 0) {
-          is_key_frame = 0;
-          break;
-        }
-      }
-      if (!is_key_frame) break;
-    }
-    if (is_key_frame) return 1;
-  }
-
-  return 0;
-}
-
-// Given 'prev' frame and current frame rectangle 'rect', convert 'curr' frame
-// to a key frame.
-static void ConvertToKeyFrame(const WebPPicture* const prev,
-                              WebPFrameRect* const rect,
-                              WebPPicture* const curr) {
-  int j;
-  assert(curr->width == prev->width && curr->height == prev->height);
-
-  // Replace transparent pixels of current canvas with those from previous
-  // canvas (with previous frame disposed).
-  for (j = 0; j < curr->height; ++j) {
-    int i;
-    for (i = 0; i < curr->width; ++i) {
-      uint32_t* const curr_pixel = curr->argb + j * curr->argb_stride + i;
-      const int curr_alpha = *curr_pixel >> 24;
-      if (curr_alpha == 0) {
-        *curr_pixel = prev->argb[j * prev->argb_stride + i];
-      }
-    }
-  }
-
-  // Frame rectangle now covers the whole canvas.
-  rect->x_offset = 0;
-  rect->y_offset = 0;
-  rect->width = curr->width;
-  rect->height = curr->height;
-}
-
-//------------------------------------------------------------------------------
-// Encoded frame.
-
-// Used to store two candidates of encoded data for an animation frame. One of
-// the two will be chosen later.
-typedef struct {
-  WebPMuxFrameInfo sub_frame;  // Encoded frame rectangle.
-  WebPMuxFrameInfo key_frame;  // Encoded frame if it was converted to keyframe.
-} EncodedFrame;
-
-// Release the data contained by 'encoded_frame'.
-static void FrameRelease(EncodedFrame* const encoded_frame) {
-  if (encoded_frame != NULL) {
-    WebPDataClear(&encoded_frame->sub_frame.bitstream);
-    WebPDataClear(&encoded_frame->key_frame.bitstream);
-    memset(encoded_frame, 0, sizeof(*encoded_frame));
-  }
-}
-
-//------------------------------------------------------------------------------
-// Frame cache.
-
-// Used to store encoded frames that haven't been output yet.
-struct WebPFrameCache {
-  EncodedFrame* encoded_frames;  // Array of encoded frames.
-  size_t size;               // Number of allocated data elements.
-  size_t start;              // Start index.
-  size_t count;              // Number of valid data elements.
-  int flush_count;           // If >0, ‘flush_count’ frames starting from
-                             // 'start' are ready to be added to mux.
-  int64_t best_delta;        // min(canvas size - frame size) over the frames.
-                             // Can be negative in certain cases due to
-                             // transparent pixels in a frame.
-  int keyframe;              // Index of selected keyframe relative to 'start'.
-
-  size_t kmin;                   // Min distance between key frames.
-  size_t kmax;                   // Max distance between key frames.
-  size_t count_since_key_frame;  // Frames seen since the last key frame.
-  int allow_mixed;           // If true, each frame can be lossy or lossless.
-  WebPPicture prev_canvas;   // Previous canvas (properly disposed).
-  WebPPicture curr_canvas;   // Current canvas (temporary buffer).
-  int is_first_frame;        // True if no frames have been added to the cache
-                             // since WebPFrameCacheNew().
-};
-
-// Reset the counters in the cache struct. Doesn't touch 'cache->encoded_frames'
-// and 'cache->size'.
-static void CacheReset(WebPFrameCache* const cache) {
-  cache->start = 0;
-  cache->count = 0;
-  cache->flush_count = 0;
-  cache->best_delta = DELTA_INFINITY;
-  cache->keyframe = KEYFRAME_NONE;
-}
-
-WebPFrameCache* WebPFrameCacheNew(int width, int height,
-                                  size_t kmin, size_t kmax, int allow_mixed) {
-  WebPFrameCache* cache = (WebPFrameCache*)malloc(sizeof(*cache));
-  if (cache == NULL) return NULL;
-  CacheReset(cache);
-  // sanity init, so we can call WebPFrameCacheDelete():
-  cache->encoded_frames = NULL;
-
-  cache->is_first_frame = 1;
-
-  // Picture buffers.
-  if (!WebPPictureInit(&cache->prev_canvas) ||
-      !WebPPictureInit(&cache->curr_canvas)) {
-    return NULL;
-  }
-  cache->prev_canvas.width = width;
-  cache->prev_canvas.height = height;
-  cache->prev_canvas.use_argb = 1;
-  if (!WebPPictureAlloc(&cache->prev_canvas) ||
-      !WebPPictureCopy(&cache->prev_canvas, &cache->curr_canvas)) {
-    goto Err;
-  }
-  WebPUtilClearPic(&cache->prev_canvas, NULL);
-
-  // Cache data.
-  cache->allow_mixed = allow_mixed;
-  cache->kmin = kmin;
-  cache->kmax = kmax;
-  cache->count_since_key_frame = 0;
-  assert(kmax > kmin);
-  cache->size = kmax - kmin;
-  cache->encoded_frames =
-      (EncodedFrame*)calloc(cache->size, sizeof(*cache->encoded_frames));
-  if (cache->encoded_frames == NULL) goto Err;
-
-  return cache;  // All OK.
-
- Err:
-  WebPFrameCacheDelete(cache);
-  return NULL;
-}
-
-void WebPFrameCacheDelete(WebPFrameCache* const cache) {
-  if (cache != NULL) {
-    if (cache->encoded_frames != NULL) {
-      size_t i;
-      for (i = 0; i < cache->size; ++i) {
-        FrameRelease(&cache->encoded_frames[i]);
-      }
-      free(cache->encoded_frames);
-    }
-    WebPPictureFree(&cache->prev_canvas);
-    WebPPictureFree(&cache->curr_canvas);
-    free(cache);
-  }
-}
-
-static int EncodeFrame(const WebPConfig* const config, WebPPicture* const pic,
-                       WebPMemoryWriter* const memory) {
-  pic->use_argb = 1;
-  pic->writer = WebPMemoryWrite;
-  pic->custom_ptr = memory;
-  if (!WebPEncode(config, pic)) {
-    return 0;
-  }
-  return 1;
-}
-
-static void GetEncodedData(const WebPMemoryWriter* const memory,
-                           WebPData* const encoded_data) {
-  encoded_data->bytes = memory->mem;
-  encoded_data->size  = memory->size;
-}
-
-#define MIN_COLORS_LOSSY     31  // Don't try lossy below this threshold.
-#define MAX_COLORS_LOSSLESS 194  // Don't try lossless above this threshold.
-#define MAX_COLOR_COUNT     256  // Power of 2 greater than MAX_COLORS_LOSSLESS.
-#define HASH_SIZE (MAX_COLOR_COUNT * 4)
-#define HASH_RIGHT_SHIFT     22  // 32 - log2(HASH_SIZE).
-
-// TODO(urvang): Also used in enc/vp8l.c. Move to utils.
-// If the number of colors in the 'pic' is at least MAX_COLOR_COUNT, return
-// MAX_COLOR_COUNT. Otherwise, return the exact number of colors in the 'pic'.
-static int GetColorCount(const WebPPicture* const pic) {
-  int x, y;
-  int num_colors = 0;
-  uint8_t in_use[HASH_SIZE] = { 0 };
-  uint32_t colors[HASH_SIZE];
-  static const uint32_t kHashMul = 0x1e35a7bd;
-  const uint32_t* argb = pic->argb;
-  const int width = pic->width;
-  const int height = pic->height;
-  uint32_t last_pix = ~argb[0];   // so we're sure that last_pix != argb[0]
-
-  for (y = 0; y < height; ++y) {
-    for (x = 0; x < width; ++x) {
-      int key;
-      if (argb[x] == last_pix) {
-        continue;
-      }
-      last_pix = argb[x];
-      key = (kHashMul * last_pix) >> HASH_RIGHT_SHIFT;
-      while (1) {
-        if (!in_use[key]) {
-          colors[key] = last_pix;
-          in_use[key] = 1;
-          ++num_colors;
-          if (num_colors >= MAX_COLOR_COUNT) {
-            return MAX_COLOR_COUNT;  // Exact count not needed.
-          }
-          break;
-        } else if (colors[key] == last_pix) {
-          break;  // The color is already there.
-        } else {
-          // Some other color sits here, so do linear conflict resolution.
-          ++key;
-          key &= (HASH_SIZE - 1);  // Key mask.
-        }
-      }
-    }
-    argb += pic->argb_stride;
-  }
-  return num_colors;
-}
-
-#undef MAX_COLOR_COUNT
-#undef HASH_SIZE
-#undef HASH_RIGHT_SHIFT
-
-static int SetFrame(const WebPConfig* const config, int allow_mixed,
-                    int is_key_frame, const WebPPicture* const prev_canvas,
-                    WebPPicture* const frame, const WebPFrameRect* const rect,
-                    const WebPMuxFrameInfo* const info,
-                    WebPPicture* const sub_frame, EncodedFrame* encoded_frame) {
-  int try_lossless;
-  int try_lossy;
-  int try_both;
-  WebPMemoryWriter mem1, mem2;
-  WebPData* encoded_data;
-  WebPMuxFrameInfo* const dst =
-      is_key_frame ? &encoded_frame->key_frame : &encoded_frame->sub_frame;
-  *dst = *info;
-  encoded_data = &dst->bitstream;
-  WebPMemoryWriterInit(&mem1);
-  WebPMemoryWriterInit(&mem2);
-
-  if (!allow_mixed) {
-    try_lossless = config->lossless;
-    try_lossy = !try_lossless;
-  } else {  // Use a heuristic for trying lossless and/or lossy compression.
-    const int num_colors = GetColorCount(sub_frame);
-    try_lossless = (num_colors < MAX_COLORS_LOSSLESS);
-    try_lossy = (num_colors >= MIN_COLORS_LOSSY);
-  }
-  try_both = try_lossless && try_lossy;
-
-  if (try_lossless) {
-    WebPConfig config_ll = *config;
-    config_ll.lossless = 1;
-    if (!EncodeFrame(&config_ll, sub_frame, &mem1)) {
-      goto Err;
-    }
-  }
-
-  if (try_lossy) {
-    WebPConfig config_lossy = *config;
-    config_lossy.lossless = 0;
-    if (!is_key_frame) {
-      // For lossy compression of a frame, it's better to replace transparent
-      // pixels of 'curr' with actual RGB values, whenever possible.
-      ReduceTransparency(prev_canvas, rect, frame);
-      // TODO(later): Investigate if this helps lossless compression as well.
-      FlattenSimilarBlocks(prev_canvas, rect, frame);
-    }
-    if (!EncodeFrame(&config_lossy, sub_frame, &mem2)) {
-      goto Err;
-    }
-  }
-
-  if (try_both) {  // Pick the encoding with smallest size.
-    // TODO(later): Perhaps a rough SSIM/PSNR produced by the encoder should
-    // also be a criteria, in addition to sizes.
-    if (mem1.size <= mem2.size) {
-      free(mem2.mem);
-      GetEncodedData(&mem1, encoded_data);
-    } else {
-      free(mem1.mem);
-      GetEncodedData(&mem2, encoded_data);
-    }
-  } else {
-    GetEncodedData(try_lossless ? &mem1 : &mem2, encoded_data);
-  }
-  return 1;
-
- Err:
-  free(mem1.mem);
-  free(mem2.mem);
-  return 0;
-}
-
-#undef MIN_COLORS_LOSSY
-#undef MAX_COLORS_LOSSLESS
-
-// Returns cached frame at given 'position' index.
-static EncodedFrame* CacheGetFrame(const WebPFrameCache* const cache,
-                                   size_t position) {
-  assert(cache->start + position < cache->size);
-  return &cache->encoded_frames[cache->start + position];
-}
-
-// Calculate the penalty incurred if we encode given frame as a key frame
-// instead of a sub-frame.
-static int64_t KeyFramePenalty(const EncodedFrame* const encoded_frame) {
-  return ((int64_t)encoded_frame->key_frame.bitstream.size -
-          encoded_frame->sub_frame.bitstream.size);
-}
-
-static void DisposeFrame(WebPMuxAnimDispose dispose_method,
-                         const WebPFrameRect* const gif_rect,
-                         WebPPicture* const frame, WebPPicture* const canvas) {
-  if (dispose_method == WEBP_MUX_DISPOSE_BACKGROUND) {
-    WebPUtilClearPic(frame, NULL);
-    WebPUtilClearPic(canvas, gif_rect);
-  }
-}
-
-int WebPFrameCacheAddFrame(WebPFrameCache* const cache,
-                           const WebPConfig* const config,
-                           const WebPFrameRect* const orig_rect,
-                           WebPPicture* const frame,
-                           WebPMuxFrameInfo* const info) {
-  int ok = 0;
-  WebPFrameRect rect = *orig_rect;
-  WebPPicture sub_image;  // View extracted from 'frame' with rectangle 'rect'.
-  WebPPicture* const prev_canvas = &cache->prev_canvas;
-  const size_t position = cache->count;
-  const int allow_mixed = cache->allow_mixed;
-  EncodedFrame* const encoded_frame = CacheGetFrame(cache, position);
-  assert(position < cache->size);
-
-  // Snap to even offsets (and adjust dimensions if needed).
-  rect.width += (rect.x_offset & 1);
-  rect.height += (rect.y_offset & 1);
-  rect.x_offset &= ~1;
-  rect.y_offset &= ~1;
-
-  if (!WebPPictureView(frame, rect.x_offset, rect.y_offset,
-                       rect.width, rect.height, &sub_image)) {
-    return 0;
-  }
-  info->x_offset = rect.x_offset;
-  info->y_offset = rect.y_offset;
-
-  ++cache->count;
-
-  if (cache->is_first_frame || IsKeyFrame(frame, &rect, prev_canvas)) {
-    // Add this as a key frame.
-    if (!SetFrame(config, allow_mixed, 1, NULL, NULL, NULL, info, &sub_image,
-                  encoded_frame)) {
-      goto End;
-    }
-    cache->keyframe = position;
-    cache->flush_count = cache->count;
-    cache->count_since_key_frame = 0;
-    // Update prev_canvas by simply copying from 'curr'.
-    CopyPixels(frame, prev_canvas);
-  } else {
-    ++cache->count_since_key_frame;
-    if (cache->count_since_key_frame <= cache->kmin) {
-      // Add this as a frame rectangle.
-      if (!SetFrame(config, allow_mixed, 0, prev_canvas, frame, &rect, info,
-                    &sub_image, encoded_frame)) {
-        goto End;
-      }
-      cache->flush_count = cache->count;
-      // Update prev_canvas by blending 'curr' into it.
-      BlendPixels(frame, orig_rect, prev_canvas);
-    } else {
-      WebPPicture full_image;
-      WebPMuxFrameInfo full_image_info;
-      int frame_added;
-      int64_t curr_delta;
-
-      // Add frame rectangle to cache.
-      if (!SetFrame(config, allow_mixed, 0, prev_canvas, frame, &rect, info,
-                    &sub_image, encoded_frame)) {
-        goto End;
-      }
-
-      // Convert to a key frame.
-      CopyPixels(frame, &cache->curr_canvas);
-      ConvertToKeyFrame(prev_canvas, &rect, &cache->curr_canvas);
-      if (!WebPPictureView(&cache->curr_canvas, rect.x_offset, rect.y_offset,
-                           rect.width, rect.height, &full_image)) {
-        goto End;
-      }
-      full_image_info = *info;
-      full_image_info.x_offset = rect.x_offset;
-      full_image_info.y_offset = rect.y_offset;
-
-      // Add key frame to cache, too.
-      frame_added = SetFrame(config, allow_mixed, 1, NULL, NULL, NULL,
-                             &full_image_info, &full_image, encoded_frame);
-      WebPPictureFree(&full_image);
-      if (!frame_added) goto End;
-
-      // Analyze size difference of the two variants.
-      curr_delta = KeyFramePenalty(encoded_frame);
-      if (curr_delta <= cache->best_delta) {  // Pick this as keyframe.
-        cache->keyframe = position;
-        cache->best_delta = curr_delta;
-        cache->flush_count = cache->count - 1;  // We can flush previous frames.
-      }
-      if (cache->count_since_key_frame == cache->kmax) {
-        cache->flush_count = cache->count;
-        cache->count_since_key_frame = 0;
-      }
-
-      // Update prev_canvas by simply copying from 'curr_canvas'.
-      CopyPixels(&cache->curr_canvas, prev_canvas);
-    }
-  }
-
-  DisposeFrame(info->dispose_method, orig_rect, frame, prev_canvas);
-
-  cache->is_first_frame = 0;
-  ok = 1;
-
- End:
-  WebPPictureFree(&sub_image);
-  if (!ok) {
-    FrameRelease(encoded_frame);
-    --cache->count;  // We reset the count, as the frame addition failed.
-  }
-  return ok;
-}
-
-WebPMuxError WebPFrameCacheFlush(WebPFrameCache* const cache, int verbose,
-                                 WebPMux* const mux) {
-  while (cache->flush_count > 0) {
-    WebPMuxFrameInfo* info;
-    WebPMuxError err;
-    EncodedFrame* const curr = CacheGetFrame(cache, 0);
-    // Pick frame or full canvas.
-    if (cache->keyframe == 0) {
-      info = &curr->key_frame;
-      info->blend_method = WEBP_MUX_NO_BLEND;
-      cache->keyframe = KEYFRAME_NONE;
-      cache->best_delta = DELTA_INFINITY;
-    } else {
-      info = &curr->sub_frame;
-      info->blend_method = WEBP_MUX_BLEND;
-    }
-    // Add to mux.
-    err = WebPMuxPushFrame(mux, info, 1);
-    if (err != WEBP_MUX_OK) return err;
-    if (verbose) {
-      printf("Added frame. offset:%d,%d duration:%d dispose:%d blend:%d\n",
-             info->x_offset, info->y_offset, info->duration,
-             info->dispose_method, info->blend_method);
-    }
-    FrameRelease(curr);
-    ++cache->start;
-    --cache->flush_count;
-    --cache->count;
-    if (cache->keyframe != KEYFRAME_NONE) --cache->keyframe;
-  }
-
-  if (cache->count == 0) CacheReset(cache);
-  return WEBP_MUX_OK;
-}
-
-WebPMuxError WebPFrameCacheFlushAll(WebPFrameCache* const cache, int verbose,
-                                    WebPMux* const mux) {
-  cache->flush_count = cache->count;  // Force flushing of all frames.
-  return WebPFrameCacheFlush(cache, verbose, mux);
-}
-
-//------------------------------------------------------------------------------

examples/gif2webp_util.h

@@ -1,80 +0,0 @@
-// Copyright 2013 Google Inc. All Rights Reserved.
-//
-// Use of this source code is governed by a BSD-style license
-// that can be found in the COPYING file in the root of the source
-// tree. An additional intellectual property rights grant can be found
-// in the file PATENTS. All contributing project authors may
-// be found in the AUTHORS file in the root of the source tree.
-// -----------------------------------------------------------------------------
-//
-//  Helper structs and methods for gif2webp tool.
-//
-// Author: Urvang (urvang@google.com)
-
-#ifndef WEBP_EXAMPLES_GIF2WEBP_UTIL_H_
-#define WEBP_EXAMPLES_GIF2WEBP_UTIL_H_
-
-#include <stdlib.h>
-
-#include "webp/mux.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-//------------------------------------------------------------------------------
-// Helper utilities.
-
-#define WEBP_UTIL_TRANSPARENT_COLOR 0x00ffffff
-
-struct WebPPicture;
-
-typedef struct {
-  int x_offset, y_offset, width, height;
-} WebPFrameRect;
-
-// Clear pixels in 'picture' within given 'rect' to transparent color.
-void WebPUtilClearPic(struct WebPPicture* const picture,
-                      const WebPFrameRect* const rect);
-
-//------------------------------------------------------------------------------
-// Frame cache.
-
-typedef struct WebPFrameCache WebPFrameCache;
-
-// Given the minimum distance between key frames 'kmin' and maximum distance
-// between key frames 'kmax', returns an appropriately allocated cache object.
-// If 'allow_mixed' is true, the subsequent calls to WebPFrameCacheAddFrame()
-// will heuristically pick lossy or lossless compression for each frame.
-// Use WebPFrameCacheDelete() to deallocate the 'cache'.
-WebPFrameCache* WebPFrameCacheNew(int width, int height,
-                                  size_t kmin, size_t kmax, int allow_mixed);
-
-// Release all the frame data from 'cache' and free 'cache'.
-void WebPFrameCacheDelete(WebPFrameCache* const cache);
-
-// Given an image described by 'frame', 'info' and 'orig_rect', optimize it for
-// WebP, encode it and add it to 'cache'.
-// This takes care of frame disposal too, according to 'info->dispose_method'.
-int WebPFrameCacheAddFrame(WebPFrameCache* const cache,
-                           const WebPConfig* const config,
-                           const WebPFrameRect* const orig_rect,
-                           WebPPicture* const frame,
-                           WebPMuxFrameInfo* const info);
-
-// Flush the *ready* frames from cache and add them to 'mux'. If 'verbose' is
-// true, prints the information about these frames.
-WebPMuxError WebPFrameCacheFlush(WebPFrameCache* const cache, int verbose,
-                                 WebPMux* const mux);
-
-// Similar to 'WebPFrameCacheFlushFrames()', but flushes *all* the frames.
-WebPMuxError WebPFrameCacheFlushAll(WebPFrameCache* const cache, int verbose,
-                                    WebPMux* const mux);
-
-//------------------------------------------------------------------------------
-
-#ifdef __cplusplus
-}    // extern "C"
-#endif
-
-#endif  // WEBP_EXAMPLES_GIF2WEBP_UTIL_H_

examples/gifdec.c

@@ -0,0 +1,416 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// GIF decode.
+
+#include "./gifdec.h"
+
+#include <stdio.h>
+
+#ifdef WEBP_HAVE_GIF
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "webp/encode.h"
+#include "webp/mux_types.h"
+
+#define GIF_TRANSPARENT_COLOR 0x00000000u
+#define GIF_WHITE_COLOR       0xffffffffu
+#define GIF_TRANSPARENT_MASK  0x01
+#define GIF_DISPOSE_MASK      0x07
+#define GIF_DISPOSE_SHIFT     2
+
+// from utils/utils.h
+#ifdef __cplusplus
+extern "C" {
+#endif
+extern void WebPCopyPlane(const uint8_t* src, int src_stride,
+                          uint8_t* dst, int dst_stride,
+                          int width, int height);
+extern void WebPCopyPixels(const WebPPicture* const src,
+                           WebPPicture* const dst);
+#ifdef __cplusplus
+}
+#endif
+
+void GIFGetBackgroundColor(const ColorMapObject* const color_map,
+                           int bgcolor_index, int transparent_index,
+                           uint32_t* const bgcolor) {
+  if (transparent_index != GIF_INDEX_INVALID &&
+      bgcolor_index == transparent_index) {
+    *bgcolor = GIF_TRANSPARENT_COLOR;  // Special case.
+  } else if (color_map == NULL || color_map->Colors == NULL
+             || bgcolor_index >= color_map->ColorCount) {
+    *bgcolor = GIF_WHITE_COLOR;
+    fprintf(stderr,
+            "GIF decode warning: invalid background color index. Assuming "
+            "white background.\n");
+  } else {
+    const GifColorType color = color_map->Colors[bgcolor_index];
+    *bgcolor = (0xffu       << 24)
+             | (color.Red   << 16)
+             | (color.Green <<  8)
+             | (color.Blue  <<  0);
+  }
+}
+
+int GIFReadGraphicsExtension(const GifByteType* const buf, int* const duration,
+                             GIFDisposeMethod* const dispose,
+                             int* const transparent_index) {
+  const int flags = buf[1];
+  const int dispose_raw = (flags >> GIF_DISPOSE_SHIFT) & GIF_DISPOSE_MASK;
+  const int duration_raw = buf[2] | (buf[3] << 8);  // In 10 ms units.
+  if (buf[0] != 4) return 0;
+  *duration = duration_raw * 10;  // Duration is in 1 ms units.
+  switch (dispose_raw) {
+    case 3:
+      *dispose = GIF_DISPOSE_RESTORE_PREVIOUS;
+      break;
+    case 2:
+      *dispose = GIF_DISPOSE_BACKGROUND;
+      break;
+    case 1:
+    case 0:
+    default:
+      *dispose = GIF_DISPOSE_NONE;
+      break;
+  }
+  *transparent_index =
+      (flags & GIF_TRANSPARENT_MASK) ? buf[4] : GIF_INDEX_INVALID;
+  return 1;
+}
+
+static int Remap(const GifFileType* const gif, const uint8_t* const src,
+                 int len, int transparent_index, uint32_t* dst) {
+  int i;
+  const GifColorType* colors;
+  const ColorMapObject* const cmap =
+      gif->Image.ColorMap ? gif->Image.ColorMap : gif->SColorMap;
+  if (cmap == NULL) return 1;
+  if (cmap->Colors == NULL || cmap->ColorCount <= 0) return 0;
+  colors = cmap->Colors;
+
+  for (i = 0; i < len; ++i) {
+    if (src[i] == transparent_index) {
+      dst[i] = GIF_TRANSPARENT_COLOR;
+    } else if (src[i] < cmap->ColorCount) {
+      const GifColorType c = colors[src[i]];
+      dst[i] = c.Blue | (c.Green << 8) | (c.Red << 16) | (0xffu << 24);
+    } else {
+      return 0;
+    }
+  }
+  return 1;
+}
+
+int GIFReadFrame(GifFileType* const gif, int transparent_index,
+                 GIFFrameRect* const gif_rect, WebPPicture* const picture) {
+  WebPPicture sub_image;
+  const GifImageDesc* const image_desc = &gif->Image;
+  uint32_t* dst = NULL;
+  uint8_t* tmp = NULL;
+  const GIFFrameRect rect = {
+      image_desc->Left, image_desc->Top, image_desc->Width, image_desc->Height
+  };
+  const uint64_t memory_needed = 4 * rect.width * (uint64_t)rect.height;
+  int ok = 0;
+  *gif_rect = rect;
+
+  if (memory_needed != (size_t)memory_needed || memory_needed > (4ULL << 32)) {
+    fprintf(stderr, "Image is too large (%d x %d).", rect.width, rect.height);
+    return 0;
+  }
+
+  // Use a view for the sub-picture:
+  if (!WebPPictureView(picture, rect.x_offset, rect.y_offset,
+                       rect.width, rect.height, &sub_image)) {
+    fprintf(stderr, "Sub-image %dx%d at position %d,%d is invalid!\n",
+            rect.width, rect.height, rect.x_offset, rect.y_offset);
+    return 0;
+  }
+  dst = sub_image.argb;
+
+  tmp = (uint8_t*)WebPMalloc(rect.width * sizeof(*tmp));
+  if (tmp == NULL) goto End;
+
+  if (image_desc->Interlace) {  // Interlaced image.
+    // We need 4 passes, with the following offsets and jumps.
+    const int interlace_offsets[] = { 0, 4, 2, 1 };
+    const int interlace_jumps[]   = { 8, 8, 4, 2 };
+    int pass;
+    for (pass = 0; pass < 4; ++pass) {
+      const size_t stride = (size_t)sub_image.argb_stride;
+      int y = interlace_offsets[pass];
+      uint32_t* row = dst + y * stride;
+      const size_t jump = interlace_jumps[pass] * stride;
+      for (; y < rect.height; y += interlace_jumps[pass], row += jump) {
+        if (DGifGetLine(gif, tmp, rect.width) == GIF_ERROR) goto End;
+        if (!Remap(gif, tmp, rect.width, transparent_index, row)) goto End;
+      }
+    }
+  } else {  // Non-interlaced image.
+    int y;
+    uint32_t* ptr = dst;
+    for (y = 0; y < rect.height; ++y, ptr += sub_image.argb_stride) {
+      if (DGifGetLine(gif, tmp, rect.width) == GIF_ERROR) goto End;
+      if (!Remap(gif, tmp, rect.width, transparent_index, ptr)) goto End;
+    }
+  }
+  ok = 1;
+
+ End:
+  if (!ok) picture->error_code = sub_image.error_code;
+  WebPPictureFree(&sub_image);
+  WebPFree(tmp);
+  return ok;
+}
+
+int GIFReadLoopCount(GifFileType* const gif, GifByteType** const buf,
+                     int* const loop_count) {
+  assert(!memcmp(*buf + 1, "NETSCAPE2.0", 11) ||
+         !memcmp(*buf + 1, "ANIMEXTS1.0", 11));
+  if (DGifGetExtensionNext(gif, buf) == GIF_ERROR) {
+    return 0;
+  }
+  if (*buf == NULL) {
+    return 0;  // Loop count sub-block missing.
+  }
+  if ((*buf)[0] < 3 || (*buf)[1] != 1) {
+    return 0;   // wrong size/marker
+  }
+  *loop_count = (*buf)[2] | ((*buf)[3] << 8);
+  return 1;
+}
+
+int GIFReadMetadata(GifFileType* const gif, GifByteType** const buf,
+                    WebPData* const metadata) {
+  const int is_xmp = !memcmp(*buf + 1, "XMP DataXMP", 11);
+  const int is_icc = !memcmp(*buf + 1, "ICCRGBG1012", 11);
+  assert(is_xmp || is_icc);
+  (void)is_icc;  // silence unused warning.
+  // Construct metadata from sub-blocks.
+  // Usual case (including ICC profile): In each sub-block, the
+  // first byte specifies its size in bytes (0 to 255) and the
+  // rest of the bytes contain the data.
+  // Special case for XMP data: In each sub-block, the first byte
+  // is also part of the XMP payload. XMP in GIF also has a 257
+  // byte padding data. See the XMP specification for details.
+  while (1) {
+    WebPData subblock;
+    const uint8_t* tmp;
+    if (DGifGetExtensionNext(gif, buf) == GIF_ERROR) {
+      return 0;
+    }
+    if (*buf == NULL) break;  // Finished.
+    subblock.size = is_xmp ? (*buf)[0] + 1 : (*buf)[0];
+    assert(subblock.size > 0);
+    subblock.bytes = is_xmp ? *buf : *buf + 1;
+    // Note: We store returned value in 'tmp' first, to avoid
+    // leaking old memory in metadata->bytes on error.
+    tmp = (uint8_t*)realloc((void*)metadata->bytes,
+                            metadata->size + subblock.size);
+    if (tmp == NULL) {
+      return 0;
+    }
+    memcpy((void*)(tmp + metadata->size),
+           subblock.bytes, subblock.size);
+    metadata->bytes = tmp;
+    metadata->size += subblock.size;
+  }
+  if (is_xmp) {
+    // XMP padding data is 0x01, 0xff, 0xfe ... 0x01, 0x00.
+    const size_t xmp_pading_size = 257;
+    if (metadata->size > xmp_pading_size) {
+      metadata->size -= xmp_pading_size;
+    }
+  }
+  return 1;
+}
+
+static void ClearRectangle(WebPPicture* const picture,
+                           int left, int top, int width, int height) {
+  int i, j;
+  const size_t stride = picture->argb_stride;
+  uint32_t* dst = picture->argb + top * stride + left;
+  for (j = 0; j < height; ++j, dst += stride) {
+    for (i = 0; i < width; ++i) dst[i] = GIF_TRANSPARENT_COLOR;
+  }
+}
+
+void GIFClearPic(WebPPicture* const pic, const GIFFrameRect* const rect) {
+  if (rect != NULL) {
+    ClearRectangle(pic, rect->x_offset, rect->y_offset,
+                   rect->width, rect->height);
+  } else {
+    ClearRectangle(pic, 0, 0, pic->width, pic->height);
+  }
+}
+
+void GIFCopyPixels(const WebPPicture* const src, WebPPicture* const dst) {
+  WebPCopyPixels(src, dst);
+}
+
+void GIFDisposeFrame(GIFDisposeMethod dispose, const GIFFrameRect* const rect,
+                     const WebPPicture* const prev_canvas,
+                     WebPPicture* const curr_canvas) {
+  assert(rect != NULL);
+  if (dispose == GIF_DISPOSE_BACKGROUND) {
+    GIFClearPic(curr_canvas, rect);
+  } else if (dispose == GIF_DISPOSE_RESTORE_PREVIOUS) {
+    const size_t src_stride = prev_canvas->argb_stride;
+    const uint32_t* const src = prev_canvas->argb + rect->x_offset
+                              + rect->y_offset * src_stride;
+    const size_t dst_stride = curr_canvas->argb_stride;
+    uint32_t* const dst = curr_canvas->argb + rect->x_offset
+                        + rect->y_offset * dst_stride;
+    assert(prev_canvas != NULL);
+    WebPCopyPlane((uint8_t*)src, (int)(4 * src_stride),
+                  (uint8_t*)dst, (int)(4 * dst_stride),
+                  4 * rect->width, rect->height);
+  }
+}
+
+void GIFBlendFrames(const WebPPicture* const src,
+                    const GIFFrameRect* const rect, WebPPicture* const dst) {
+  int i, j;
+  const size_t src_stride = src->argb_stride;
+  const size_t dst_stride = dst->argb_stride;
+  assert(src->width == dst->width && src->height == dst->height);
+  for (j = rect->y_offset; j < rect->y_offset + rect->height; ++j) {
+    for (i = rect->x_offset; i < rect->x_offset + rect->width; ++i) {
+      const uint32_t src_pixel = src->argb[j * src_stride + i];
+      const int src_alpha = src_pixel >> 24;
+      if (src_alpha != 0) {
+        dst->argb[j * dst_stride + i] = src_pixel;
+      }
+    }
+  }
+}
+
+void GIFDisplayError(const GifFileType* const gif, int gif_error) {
+  // libgif 4.2.0 has retired PrintGifError() and added GifErrorString().
+#if LOCAL_GIF_PREREQ(4,2)
+#if LOCAL_GIF_PREREQ(5,0)
+  // Static string actually, hence the const char* cast.
+  const char* error_str = (const char*)GifErrorString(
+      (gif == NULL) ? gif_error : gif->Error);
+#else
+  const char* error_str = (const char*)GifErrorString();
+  (void)gif;
+#endif
+  if (error_str == NULL) error_str = "Unknown error";
+  fprintf(stderr, "GIFLib Error %d: %s\n", gif_error, error_str);
+#else
+  (void)gif;
+  fprintf(stderr, "GIFLib Error %d: ", gif_error);
+  PrintGifError();
+  fprintf(stderr, "\n");
+#endif
+}
+
+#else  // !WEBP_HAVE_GIF
+
+static void ErrorGIFNotAvailable() {
+  fprintf(stderr, "GIF support not compiled. Please install the libgif-dev "
+          "package before building.\n");
+}
+
+void GIFGetBackgroundColor(const struct ColorMapObject* const color_map,
+                           int bgcolor_index, int transparent_index,
+                           uint32_t* const bgcolor) {
+  (void)color_map;
+  (void)bgcolor_index;
+  (void)transparent_index;
+  (void)bgcolor;
+  ErrorGIFNotAvailable();
+}
+
+int GIFReadGraphicsExtension(const GifByteType* const data, int* const duration,
+                             GIFDisposeMethod* const dispose,
+                             int* const transparent_index) {
+  (void)data;
+  (void)duration;
+  (void)dispose;
+  (void)transparent_index;
+  ErrorGIFNotAvailable();
+  return 0;
+}
+
+int GIFReadFrame(struct GifFileType* const gif, int transparent_index,
+                 GIFFrameRect* const gif_rect,
+                 struct WebPPicture* const picture) {
+  (void)gif;
+  (void)transparent_index;
+  (void)gif_rect;
+  (void)picture;
+  ErrorGIFNotAvailable();
+  return 0;
+}
+
+int GIFReadLoopCount(struct GifFileType* const gif, GifByteType** const buf,
+                     int* const loop_count) {
+  (void)gif;
+  (void)buf;
+  (void)loop_count;
+  ErrorGIFNotAvailable();
+  return 0;
+}
+
+int GIFReadMetadata(struct GifFileType* const gif, GifByteType** const buf,
+                    struct WebPData* const metadata) {
+  (void)gif;
+  (void)buf;
+  (void)metadata;
+  ErrorGIFNotAvailable();
+  return 0;
+}
+
+void GIFDisposeFrame(GIFDisposeMethod dispose, const GIFFrameRect* const rect,
+                     const struct WebPPicture* const prev_canvas,
+                     struct WebPPicture* const curr_canvas) {
+  (void)dispose;
+  (void)rect;
+  (void)prev_canvas;
+  (void)curr_canvas;
+  ErrorGIFNotAvailable();
+}
+
+void GIFBlendFrames(const struct WebPPicture* const src,
+                    const GIFFrameRect* const rect,
+                    struct WebPPicture* const dst) {
+  (void)src;
+  (void)rect;
+  (void)dst;
+  ErrorGIFNotAvailable();
+}
+
+void GIFDisplayError(const struct GifFileType* const gif, int gif_error) {
+  (void)gif;
+  (void)gif_error;
+  ErrorGIFNotAvailable();
+}
+
+void GIFClearPic(struct WebPPicture* const pic,
+                 const GIFFrameRect* const rect) {
+  (void)pic;
+  (void)rect;
+  ErrorGIFNotAvailable();
+}
+
+void GIFCopyPixels(const struct WebPPicture* const src,
+                   struct WebPPicture* const dst) {
+  (void)src;
+  (void)dst;
+  ErrorGIFNotAvailable();
+}
+
+#endif  // WEBP_HAVE_GIF
+
+// -----------------------------------------------------------------------------

examples/gifdec.h

@@ -0,0 +1,116 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// GIF decode.
+
+#ifndef WEBP_EXAMPLES_GIFDEC_H_
+#define WEBP_EXAMPLES_GIFDEC_H_
+
+#include <stdio.h>
+#include "webp/types.h"
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#ifdef WEBP_HAVE_GIF
+#include <gif_lib.h>
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// GIFLIB_MAJOR is only defined in libgif >= 4.2.0.
+#if defined(GIFLIB_MAJOR) && defined(GIFLIB_MINOR)
+# define LOCAL_GIF_VERSION ((GIFLIB_MAJOR << 8) | GIFLIB_MINOR)
+# define LOCAL_GIF_PREREQ(maj, min) \
+    (LOCAL_GIF_VERSION >= (((maj) << 8) | (min)))
+#else
+# define LOCAL_GIF_VERSION 0
+# define LOCAL_GIF_PREREQ(maj, min) 0
+#endif
+
+#define GIF_INDEX_INVALID (-1)
+
+typedef enum GIFDisposeMethod {
+  GIF_DISPOSE_NONE,
+  GIF_DISPOSE_BACKGROUND,
+  GIF_DISPOSE_RESTORE_PREVIOUS
+} GIFDisposeMethod;
+
+typedef struct {
+  int x_offset, y_offset, width, height;
+} GIFFrameRect;
+
+struct WebPData;
+struct WebPPicture;
+
+#ifndef WEBP_HAVE_GIF
+struct ColorMapObject;
+struct GifFileType;
+typedef unsigned char GifByteType;
+#endif
+
+// Given the index of background color and transparent color, returns the
+// corresponding background color (in BGRA format) in 'bgcolor'.
+void GIFGetBackgroundColor(const struct ColorMapObject* const color_map,
+                           int bgcolor_index, int transparent_index,
+                           uint32_t* const bgcolor);
+
+// Parses the given graphics extension data to get frame duration (in 1ms
+// units), dispose method and transparent color index.
+// Returns true on success.
+int GIFReadGraphicsExtension(const GifByteType* const buf, int* const duration,
+                             GIFDisposeMethod* const dispose,
+                             int* const transparent_index);
+
+// Reads the next GIF frame from 'gif' into 'picture'. Also, returns the GIF
+// frame dimensions and offsets in 'rect'.
+// Returns true on success.
+int GIFReadFrame(struct GifFileType* const gif, int transparent_index,
+                 GIFFrameRect* const gif_rect,
+                 struct WebPPicture* const picture);
+
+// Parses loop count from the given Netscape extension data.
+int GIFReadLoopCount(struct GifFileType* const gif, GifByteType** const buf,
+                     int* const loop_count);
+
+// Parses the given ICC or XMP extension data and stores it into 'metadata'.
+// Returns true on success.
+int GIFReadMetadata(struct GifFileType* const gif, GifByteType** const buf,
+                    struct WebPData* const metadata);
+
+// Dispose the pixels within 'rect' of 'curr_canvas' based on 'dispose' method
+// and 'prev_canvas'.
+void GIFDisposeFrame(GIFDisposeMethod dispose, const GIFFrameRect* const rect,
+                     const struct WebPPicture* const prev_canvas,
+                     struct WebPPicture* const curr_canvas);
+
+// Given 'src' picture and its frame rectangle 'rect', blend it into 'dst'.
+void GIFBlendFrames(const struct WebPPicture* const src,
+                    const GIFFrameRect* const rect,
+                    struct WebPPicture* const dst);
+
+// Prints an error string based on 'gif_error'.
+void GIFDisplayError(const struct GifFileType* const gif, int gif_error);
+
+// In the given 'pic', clear the pixels in 'rect' to transparent color.
+void GIFClearPic(struct WebPPicture* const pic, const GIFFrameRect* const rect);
+
+// Copy pixels from 'src' to 'dst' honoring strides. 'src' and 'dst' are assumed
+// to be already allocated.
+void GIFCopyPixels(const struct WebPPicture* const src,
+                   struct WebPPicture* const dst);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_EXAMPLES_GIFDEC_H_

examples/img2webp.c

@@ -0,0 +1,325 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  generate an animated WebP out of a sequence of images
+//  (PNG, JPEG, ...)
+//
+//  Example usage:
+//     img2webp -o out.webp -q 40 -mixed -duration 40 input??.png
+//
+// Author: skal@google.com (Pascal Massimino)
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#include "../examples/example_util.h"
+#include "../imageio/image_dec.h"
+#include "../imageio/imageio_util.h"
+#include "./stopwatch.h"
+#include "./unicode.h"
+#include "webp/encode.h"
+#include "webp/mux.h"
+
+//------------------------------------------------------------------------------
+
+static void Help(void) {
+  printf("Usage:\n\n");
+  printf("  img2webp [file_options] [[frame_options] frame_file]...\n");
+  printf("\n");
+
+  printf("File-level options (only used at the start of compression):\n");
+  printf(" -min_size ............ minimize size\n");
+  printf(" -loop <int> .......... loop count (default: 0, = infinite loop)\n");
+  printf(" -kmax <int> .......... maximum number of frame between key-frames\n"
+         "                        (0=only keyframes)\n");
+  printf(" -kmin <int> .......... minimum number of frame between key-frames\n"
+         "                        (0=disable key-frames altogether)\n");
+  printf(" -mixed ............... use mixed lossy/lossless automatic mode\n");
+  printf(" -v ................... verbose mode\n");
+  printf(" -h ................... this help\n");
+  printf(" -version ............. print version number and exit\n");
+  printf("\n");
+
+  printf("Per-frame options (only used for subsequent images input):\n");
+  printf(" -d <int> ............. frame duration in ms (default: 100)\n");
+  printf(" -lossless  ........... use lossless mode (default)\n");
+  printf(" -lossy ... ........... use lossy mode\n");
+  printf(" -q <float> ........... quality\n");
+  printf(" -m <int> ............. method to use\n");
+
+  printf("\n");
+  printf("example: img2webp -loop 2 in0.png -lossy in1.jpg\n"
+         "                  -d 80 in2.tiff -o out.webp\n");
+  printf("\nNote: if a single file name is passed as the argument, the "
+         "arguments will be\n");
+  printf("tokenized from this file. The file name must not start with "
+         "the character '-'.\n");
+  printf("\nSupported input formats:\n  %s\n",
+         WebPGetEnabledInputFileFormats());
+}
+
+//------------------------------------------------------------------------------
+
+static int ReadImage(const char filename[], WebPPicture* const pic) {
+  const uint8_t* data = NULL;
+  size_t data_size = 0;
+  WebPImageReader reader;
+  int ok;
+#ifdef HAVE_WINCODEC_H
+  // Try to decode the file using WIC falling back to the other readers for
+  // e.g., WebP.
+  ok = ReadPictureWithWIC(filename, pic, 1, NULL);
+  if (ok) return 1;
+#endif
+  if (!ImgIoUtilReadFile(filename, &data, &data_size)) return 0;
+  reader = WebPGuessImageReader(data, data_size);
+  ok = reader(data, data_size, pic, 1, NULL);
+  WebPFree((void*)data);
+  return ok;
+}
+
+static int SetLoopCount(int loop_count, WebPData* const webp_data) {
+  int ok = 1;
+  WebPMuxError err;
+  uint32_t features;
+  WebPMuxAnimParams new_params;
+  WebPMux* const mux = WebPMuxCreate(webp_data, 1);
+  if (mux == NULL) return 0;
+
+  err = WebPMuxGetFeatures(mux, &features);
+  ok = (err == WEBP_MUX_OK);
+  if (!ok || !(features & ANIMATION_FLAG)) goto End;
+
+  err = WebPMuxGetAnimationParams(mux, &new_params);
+  ok = (err == WEBP_MUX_OK);
+  if (ok) {
+    new_params.loop_count = loop_count;
+    err = WebPMuxSetAnimationParams(mux, &new_params);
+    ok = (err == WEBP_MUX_OK);
+  }
+  if (ok) {
+    WebPDataClear(webp_data);
+    err = WebPMuxAssemble(mux, webp_data);
+    ok = (err == WEBP_MUX_OK);
+  }
+
+ End:
+  WebPMuxDelete(mux);
+  if (!ok) {
+    fprintf(stderr, "Error during loop-count setting\n");
+  }
+  return ok;
+}
+
+//------------------------------------------------------------------------------
+
+int main(int argc, const char* argv[]) {
+  const char* output = NULL;
+  WebPAnimEncoder* enc = NULL;
+  int verbose = 0;
+  int pic_num = 0;
+  int duration = 100;
+  int timestamp_ms = 0;
+  int loop_count = 0;
+  int width = 0, height = 0;
+  WebPAnimEncoderOptions anim_config;
+  WebPConfig config;
+  WebPPicture pic;
+  WebPData webp_data;
+  int c;
+  int have_input = 0;
+  CommandLineArguments cmd_args;
+  int ok;
+
+  INIT_WARGV(argc, argv);
+
+  ok = ExUtilInitCommandLineArguments(argc - 1, argv + 1, &cmd_args);
+  if (!ok) FREE_WARGV_AND_RETURN(1);
+
+  argc = cmd_args.argc_;
+  argv = cmd_args.argv_;
+
+  WebPDataInit(&webp_data);
+  if (!WebPAnimEncoderOptionsInit(&anim_config) ||
+      !WebPConfigInit(&config) ||
+      !WebPPictureInit(&pic)) {
+    fprintf(stderr, "Library version mismatch!\n");
+    ok = 0;
+    goto End;
+  }
+
+  // 1st pass of option parsing
+  for (c = 0; ok && c < argc; ++c) {
+    if (argv[c][0] == '-') {
+      int parse_error = 0;
+      if (!strcmp(argv[c], "-o") && c + 1 < argc) {
+        argv[c] = NULL;
+        output = (const char*)GET_WARGV_SHIFTED(argv, ++c);
+      } else if (!strcmp(argv[c], "-kmin") && c + 1 < argc) {
+        argv[c] = NULL;
+        anim_config.kmin = ExUtilGetInt(argv[++c], 0, &parse_error);
+      } else if (!strcmp(argv[c], "-kmax") && c + 1 < argc) {
+        argv[c] = NULL;
+        anim_config.kmax = ExUtilGetInt(argv[++c], 0, &parse_error);
+      } else if (!strcmp(argv[c], "-loop") && c + 1 < argc) {
+        argv[c] = NULL;
+        loop_count = ExUtilGetInt(argv[++c], 0, &parse_error);
+        if (loop_count < 0) {
+          fprintf(stderr, "Invalid non-positive loop-count (%d)\n", loop_count);
+          parse_error = 1;
+        }
+      } else if (!strcmp(argv[c], "-min_size")) {
+        anim_config.minimize_size = 1;
+      } else if (!strcmp(argv[c], "-mixed")) {
+        anim_config.allow_mixed = 1;
+        config.lossless = 0;
+      } else if (!strcmp(argv[c], "-v")) {
+        verbose = 1;
+      } else if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
+        Help();
+        FREE_WARGV_AND_RETURN(0);
+      } else if (!strcmp(argv[c], "-version")) {
+        const int enc_version = WebPGetEncoderVersion();
+        const int mux_version = WebPGetMuxVersion();
+        printf("WebP Encoder version: %d.%d.%d\nWebP Mux version: %d.%d.%d\n",
+               (enc_version >> 16) & 0xff, (enc_version >> 8) & 0xff,
+               enc_version & 0xff, (mux_version >> 16) & 0xff,
+               (mux_version >> 8) & 0xff, mux_version & 0xff);
+        goto End;
+      } else {
+        continue;
+      }
+      ok = !parse_error;
+      if (!ok) goto End;
+      argv[c] = NULL;   // mark option as 'parsed' during 1st pass
+    } else {
+      have_input |= 1;
+    }
+  }
+  if (!have_input) {
+    fprintf(stderr, "No input file(s) for generating animation!\n");
+    goto End;
+  }
+
+  // image-reading pass
+  pic_num = 0;
+  config.lossless = 1;
+  for (c = 0; ok && c < argc; ++c) {
+    if (argv[c] == NULL) continue;
+    if (argv[c][0] == '-') {    // parse local options
+      int parse_error = 0;
+      if (!strcmp(argv[c], "-lossy")) {
+        if (!anim_config.allow_mixed) config.lossless = 0;
+      } else if (!strcmp(argv[c], "-lossless")) {
+        if (!anim_config.allow_mixed) config.lossless = 1;
+      } else if (!strcmp(argv[c], "-q") && c + 1 < argc) {
+        config.quality = ExUtilGetFloat(argv[++c], &parse_error);
+      } else if (!strcmp(argv[c], "-m") && c + 1 < argc) {
+        config.method = ExUtilGetInt(argv[++c], 0, &parse_error);
+      } else if (!strcmp(argv[c], "-d") && c + 1 < argc) {
+        duration = ExUtilGetInt(argv[++c], 0, &parse_error);
+        if (duration <= 0) {
+          fprintf(stderr, "Invalid negative duration (%d)\n", duration);
+          parse_error = 1;
+        }
+      } else {
+        parse_error = 1;   // shouldn't be here.
+        fprintf(stderr, "Unknown option [%s]\n", argv[c]);
+      }
+      ok = !parse_error;
+      if (!ok) goto End;
+      continue;
+    }
+
+    if (ok) {
+      ok = WebPValidateConfig(&config);
+      if (!ok) {
+        fprintf(stderr, "Invalid configuration.\n");
+        goto End;
+      }
+    }
+
+    // read next input image
+    pic.use_argb = 1;
+    ok = ReadImage((const char*)GET_WARGV_SHIFTED(argv, c), &pic);
+    if (!ok) goto End;
+
+    if (enc == NULL) {
+      width  = pic.width;
+      height = pic.height;
+      enc = WebPAnimEncoderNew(width, height, &anim_config);
+      ok = (enc != NULL);
+      if (!ok) {
+        fprintf(stderr, "Could not create WebPAnimEncoder object.\n");
+      }
+    }
+
+    if (ok) {
+      ok = (width == pic.width && height == pic.height);
+      if (!ok) {
+        fprintf(stderr, "Frame #%d dimension mismatched! "
+                        "Got %d x %d. Was expecting %d x %d.\n",
+                pic_num, pic.width, pic.height, width, height);
+      }
+    }
+
+    if (ok) {
+      ok = WebPAnimEncoderAdd(enc, &pic, timestamp_ms, &config);
+      if (!ok) {
+        fprintf(stderr, "Error while adding frame #%d\n", pic_num);
+      }
+    }
+    WebPPictureFree(&pic);
+    if (!ok) goto End;
+
+    if (verbose) {
+      WFPRINTF(stderr, "Added frame #%3d at time %4d (file: %s)\n",
+               pic_num, timestamp_ms, GET_WARGV_SHIFTED(argv, c));
+    }
+    timestamp_ms += duration;
+    ++pic_num;
+  }
+
+  // add a last fake frame to signal the last duration
+  ok = ok && WebPAnimEncoderAdd(enc, NULL, timestamp_ms, NULL);
+  ok = ok && WebPAnimEncoderAssemble(enc, &webp_data);
+  if (!ok) {
+    fprintf(stderr, "Error during final animation assembly.\n");
+  }
+
+ End:
+  // free resources
+  WebPAnimEncoderDelete(enc);
+
+  if (ok && loop_count > 0) {  // Re-mux to add loop count.
+    ok = SetLoopCount(loop_count, &webp_data);
+  }
+
+  if (ok) {
+    if (output != NULL) {
+      ok = ImgIoUtilWriteFile(output, webp_data.bytes, webp_data.size);
+      if (ok) WFPRINTF(stderr, "output file: %s     ", (const W_CHAR*)output);
+    } else {
+      fprintf(stderr, "[no output file specified]   ");
+    }
+  }
+
+  if (ok) {
+    fprintf(stderr, "[%d frames, %u bytes].\n",
+            pic_num, (unsigned int)webp_data.size);
+  }
+  WebPDataClear(&webp_data);
+  ExUtilDeleteCommandLineArguments(&cmd_args);
+  FREE_WARGV_AND_RETURN(ok ? 0 : 1);
+}

examples/stopwatch.h

@@ -14,6 +14,8 @@
 #ifndef WEBP_EXAMPLES_STOPWATCH_H_
 #define WEBP_EXAMPLES_STOPWATCH_H_
 
+#include "webp/types.h"
+
 #if defined _WIN32 && !defined __GNUC__
 #include <windows.h>
 
@@ -37,6 +39,7 @@ static WEBP_INLINE double StopwatchReadAndReset(Stopwatch* watch) {
 
 
 #else    /* !_WIN32 */
+#include <string.h>  // memcpy
 #include <sys/time.h>
 
 typedef struct timeval Stopwatch;
@@ -46,12 +49,15 @@ static WEBP_INLINE void StopwatchReset(Stopwatch* watch) {
 }
 
 static WEBP_INLINE double StopwatchReadAndReset(Stopwatch* watch) {
-  const struct timeval old_value = *watch;
+  struct timeval old_value;
+  double delta_sec, delta_usec;
+  memcpy(&old_value, watch, sizeof(old_value));
   gettimeofday(watch, NULL);
-  return watch->tv_sec - old_value.tv_sec +
-      (watch->tv_usec - old_value.tv_usec) / 1000000.0;
+  delta_sec = (double)watch->tv_sec - old_value.tv_sec;
+  delta_usec = (double)watch->tv_usec - old_value.tv_usec;
+  return delta_sec + delta_usec / 1000000.0;
 }
 
 #endif   /* _WIN32 */
 
-#endif  /* WEBP_EXAMPLES_STOPWATCH_H_ */
+#endif  // WEBP_EXAMPLES_STOPWATCH_H_

examples/tiffdec.c

@@ -1,141 +0,0 @@
-// Copyright 2012 Google Inc. All Rights Reserved.
-//
-// Use of this source code is governed by a BSD-style license
-// that can be found in the COPYING file in the root of the source
-// tree. An additional intellectual property rights grant can be found
-// in the file PATENTS. All contributing project authors may
-// be found in the AUTHORS file in the root of the source tree.
-// -----------------------------------------------------------------------------
-//
-// TIFF decode.
-
-#include "./tiffdec.h"
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <stdio.h>
-
-#ifdef WEBP_HAVE_TIFF
-#include <tiffio.h>
-
-#include "webp/encode.h"
-#include "./metadata.h"
-
-static const struct {
-  ttag_t tag;
-  size_t storage_offset;
-} kTIFFMetadataMap[] = {
-  { TIFFTAG_ICCPROFILE, METADATA_OFFSET(iccp) },
-  { TIFFTAG_XMLPACKET,  METADATA_OFFSET(xmp) },
-  { 0, 0 },
-};
-
-// Returns true on success. The caller must use MetadataFree() on 'metadata' in
-// all cases.
-static int ExtractMetadataFromTIFF(TIFF* const tif, Metadata* const metadata) {
-  int i;
-  toff_t exif_ifd_offset;
-
-  for (i = 0; kTIFFMetadataMap[i].tag != 0; ++i) {
-    MetadataPayload* const payload =
-        (MetadataPayload*)((uint8_t*)metadata +
-                           kTIFFMetadataMap[i].storage_offset);
-    void* tag_data;
-    uint32 tag_data_len;
-
-    if (TIFFGetField(tif, kTIFFMetadataMap[i].tag, &tag_data_len, &tag_data) &&
-        !MetadataCopy((const char*)tag_data, tag_data_len, payload)) {
-      return 0;
-    }
-  }
-
-  // TODO(jzern): To extract the raw EXIF directory some parsing of it would be
-  // necessary to determine the overall size. In addition, value offsets in
-  // individual directory entries may need to be updated as, depending on the
-  // type, they are file based.
-  // Exif 2.2 Section 4.6.2 Tag Structure
-  // TIFF Revision 6.0 Part 1 Section 2 TIFF Structure #Image File Directory
-  if (TIFFGetField(tif, TIFFTAG_EXIFIFD, &exif_ifd_offset)) {
-    fprintf(stderr, "Warning: EXIF extraction from TIFF is unsupported.\n");
-  }
-  return 1;
-}
-
-int ReadTIFF(const char* const filename,
-             WebPPicture* const pic, int keep_alpha,
-             Metadata* const metadata) {
-  TIFF* const tif = TIFFOpen(filename, "r");
-  uint32 width, height;
-  uint32* raster;
-  int ok = 0;
-  tdir_t dircount;
-
-  if (tif == NULL) {
-    fprintf(stderr, "Error! Cannot open TIFF file '%s'\n", filename);
-    return 0;
-  }
-
-  dircount = TIFFNumberOfDirectories(tif);
-  if (dircount > 1) {
-    fprintf(stderr, "Warning: multi-directory TIFF files are not supported.\n"
-                    "Only the first will be used, %d will be ignored.\n",
-                    dircount - 1);
-  }
-
-  if (!(TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &width) &&
-        TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &height))) {
-    fprintf(stderr, "Error! Cannot retrieve TIFF image dimensions.\n");
-    return 0;
-  }
-  raster = (uint32*)_TIFFmalloc(width * height * sizeof(*raster));
-  if (raster != NULL) {
-    if (TIFFReadRGBAImageOriented(tif, width, height, raster,
-                                  ORIENTATION_TOPLEFT, 1)) {
-      const int stride = width * sizeof(*raster);
-      pic->width = width;
-      pic->height = height;
-      // TIFF data is ABGR
-#ifdef __BIG_ENDIAN__
-      TIFFSwabArrayOfLong(raster, width * height);
-#endif
-      pic->use_argb = 1;
-      ok = keep_alpha
-         ? WebPPictureImportRGBA(pic, (const uint8_t*)raster, stride)
-         : WebPPictureImportRGBX(pic, (const uint8_t*)raster, stride);
-    }
-    _TIFFfree(raster);
-  } else {
-    fprintf(stderr, "Error allocating TIFF RGBA memory!\n");
-  }
-
-  if (ok) {
-    if (metadata != NULL) {
-      ok = ExtractMetadataFromTIFF(tif, metadata);
-      if (!ok) {
-        fprintf(stderr, "Error extracting TIFF metadata!\n");
-        MetadataFree(metadata);
-        WebPPictureFree(pic);
-      }
-    }
-  }
-
-  TIFFClose(tif);
-  return ok;
-}
-#else  // !WEBP_HAVE_TIFF
-int ReadTIFF(const char* const filename,
-             struct WebPPicture* const pic, int keep_alpha,
-             struct Metadata* const metadata) {
-  (void)filename;
-  (void)pic;
-  (void)keep_alpha;
-  (void)metadata;
-  fprintf(stderr, "TIFF support not compiled. Please install the libtiff "
-          "development package before building.\n");
-  return 0;
-}
-#endif  // WEBP_HAVE_TIFF
-
-// -----------------------------------------------------------------------------

examples/unicode.h

@@ -0,0 +1,116 @@
+// Copyright 2018 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Unicode support for Windows. The main idea is to maintain an array of Unicode
+// arguments (wargv) and use it only for file paths. The regular argv is used
+// for everything else.
+//
+// Author: Yannis Guyon (yguyon@google.com)
+
+#ifndef WEBP_EXAMPLES_UNICODE_H_
+#define WEBP_EXAMPLES_UNICODE_H_
+
+#include <stdio.h>
+
+#if defined(_WIN32) && defined(_UNICODE)
+
+// wchar_t is used instead of TCHAR because we only perform additional work when
+// Unicode is enabled and because the output of CommandLineToArgvW() is wchar_t.
+
+#include <fcntl.h>
+#include <io.h>
+#include <wchar.h>
+#include <windows.h>
+#include <shellapi.h>
+
+// Create a wchar_t array containing Unicode parameters.
+#define INIT_WARGV(ARGC, ARGV)                                                \
+  int wargc;                                                                  \
+  const W_CHAR** const wargv =                                                \
+      (const W_CHAR**)CommandLineToArgvW(GetCommandLineW(), &wargc);          \
+  do {                                                                        \
+    if (wargv == NULL || wargc != (ARGC)) {                                   \
+      fprintf(stderr, "Error: Unable to get Unicode arguments.\n");           \
+      FREE_WARGV_AND_RETURN(-1);                                              \
+    }                                                                         \
+  } while (0)
+
+// Use this to get a Unicode argument (e.g. file path).
+#define GET_WARGV(UNUSED, C) wargv[C]
+// For cases where argv is shifted by one compared to wargv.
+#define GET_WARGV_SHIFTED(UNUSED, C) wargv[(C) + 1]
+#define GET_WARGV_OR_NULL() wargv
+
+// Release resources. LocalFree() is needed after CommandLineToArgvW().
+#define FREE_WARGV() LOCAL_FREE((W_CHAR** const)wargv)
+#define LOCAL_FREE(WARGV)                  \
+  do {                                     \
+    if ((WARGV) != NULL) LocalFree(WARGV); \
+  } while (0)
+
+#define W_CHAR wchar_t  // WCHAR without underscore might already be defined.
+#define TO_W_CHAR(STR) (L##STR)
+
+#define WFOPEN(ARG, OPT) _wfopen((const W_CHAR*)ARG, TO_W_CHAR(OPT))
+
+#define WFPRINTF(STREAM, STR, ...)                    \
+  do {                                                \
+    int prev_mode;                                    \
+    fflush(STREAM);                                   \
+    prev_mode = _setmode(_fileno(STREAM), _O_U8TEXT); \
+    fwprintf(STREAM, TO_W_CHAR(STR), __VA_ARGS__);    \
+    fflush(STREAM);                                   \
+    (void)_setmode(_fileno(STREAM), prev_mode);       \
+  } while (0)
+#define WPRINTF(STR, ...) WFPRINTF(stdout, STR, __VA_ARGS__)
+
+#define WSTRLEN(FILENAME) wcslen((const W_CHAR*)FILENAME)
+#define WSTRCMP(FILENAME, STR) wcscmp((const W_CHAR*)FILENAME, TO_W_CHAR(STR))
+#define WSTRRCHR(FILENAME, STR) wcsrchr((const W_CHAR*)FILENAME, TO_W_CHAR(STR))
+#define WSNPRINTF(A, B, STR, ...) _snwprintf(A, B, TO_W_CHAR(STR), __VA_ARGS__)
+
+#else
+
+#include <string.h>
+
+// Unicode file paths work as is on Unix platforms, and no extra work is done on
+// Windows either if Unicode is disabled.
+
+#define INIT_WARGV(ARGC, ARGV)
+
+#define GET_WARGV(ARGV, C) (ARGV)[C]
+#define GET_WARGV_SHIFTED(ARGV, C) (ARGV)[C]
+#define GET_WARGV_OR_NULL() NULL
+
+#define FREE_WARGV()
+#define LOCAL_FREE(WARGV)
+
+#define W_CHAR char
+#define TO_W_CHAR(STR) (STR)
+
+#define WFOPEN(ARG, OPT) fopen(ARG, OPT)
+
+#define WPRINTF(STR, ...) printf(STR, __VA_ARGS__)
+#define WFPRINTF(STREAM, STR, ...) fprintf(STREAM, STR, __VA_ARGS__)
+
+#define WSTRLEN(FILENAME) strlen(FILENAME)
+#define WSTRCMP(FILENAME, STR) strcmp(FILENAME, STR)
+#define WSTRRCHR(FILENAME, STR) strrchr(FILENAME, STR)
+#define WSNPRINTF(A, B, STR, ...) snprintf(A, B, STR, __VA_ARGS__)
+
+#endif  // defined(_WIN32) && defined(_UNICODE)
+
+// Don't forget to free wargv before returning (e.g. from main).
+#define FREE_WARGV_AND_RETURN(VALUE) \
+  do {                               \
+    FREE_WARGV();                    \
+    return (VALUE);                  \
+  } while (0)
+
+#endif  // WEBP_EXAMPLES_UNICODE_H_

examples/unicode_gif.h

@@ -0,0 +1,76 @@
+// Copyright 2018 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// giflib doesn't have a Unicode DGifOpenFileName(). Let's make one.
+//
+// Author: Yannis Guyon (yguyon@google.com)
+
+#ifndef WEBP_EXAMPLES_UNICODE_GIF_H_
+#define WEBP_EXAMPLES_UNICODE_GIF_H_
+
+#include "./unicode.h"
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"  // For WEBP_HAVE_GIF
+#endif
+
+#if defined(WEBP_HAVE_GIF)
+
+#ifdef _WIN32
+#include <fcntl.h>  // Not standard, needed for _topen and flags.
+#include <io.h>
+#endif
+
+#include <gif_lib.h>
+#include <string.h>
+#include "./gifdec.h"
+
+#if !defined(STDIN_FILENO)
+#define STDIN_FILENO 0
+#endif
+
+static GifFileType* DGifOpenFileUnicode(const W_CHAR* file_name, int* error) {
+  if (!WSTRCMP(file_name, "-")) {
+#if LOCAL_GIF_PREREQ(5, 0)
+    return DGifOpenFileHandle(STDIN_FILENO, error);
+#else
+    (void)error;
+    return DGifOpenFileHandle(STDIN_FILENO);
+#endif
+  }
+
+#if defined(_WIN32) && defined(_UNICODE)
+  {
+    int file_handle = _wopen(file_name, _O_RDONLY | _O_BINARY);
+    if (file_handle == -1) {
+      if (error != NULL) *error = D_GIF_ERR_OPEN_FAILED;
+      return NULL;
+    }
+
+#if LOCAL_GIF_PREREQ(5, 0)
+    return DGifOpenFileHandle(file_handle, error);
+#else
+    return DGifOpenFileHandle(file_handle);
+#endif
+  }
+
+#else
+
+#if LOCAL_GIF_PREREQ(5, 0)
+  return DGifOpenFileName(file_name, error);
+#else
+  return DGifOpenFileName(file_name);
+#endif
+
+#endif  // defined(_WIN32) && defined(_UNICODE)
+  // DGifCloseFile() is called later.
+}
+
+#endif  // defined(WEBP_HAVE_GIF)
+
+#endif  // WEBP_EXAMPLES_UNICODE_GIF_H_

examples/vwebp.c

@@ -11,7 +11,11 @@
 //
 // Author: Skal (pascal.massimino@gmail.com)
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include "webp/config.h"
+#endif
+
+#if defined(__unix__) || defined(__CYGWIN__)
+#define _POSIX_C_SOURCE 200112L  // for setenv
 #endif
 
 #include <stdio.h>
@@ -36,14 +40,14 @@
 #include "webp/decode.h"
 #include "webp/demux.h"
 
-#include "./example_util.h"
+#include "../examples/example_util.h"
+#include "../imageio/imageio_util.h"
+#include "./unicode.h"
 
-#ifdef _MSC_VER
+#if defined(_MSC_VER) && _MSC_VER < 1900
 #define snprintf _snprintf
 #endif
 
-static void Help(void);
-
 // Unfortunate global variables. Gathered into a struct for comfort.
 static struct {
   int has_animation;
@@ -51,7 +55,9 @@ static struct {
   int done;
   int decoding_error;
   int print_info;
+  int only_deltas;
   int use_color_profile;
+  int draw_anim_background_color;
 
   int canvas_width, canvas_height;
   int loop_count;
@@ -65,6 +71,7 @@ static struct {
   WebPIterator curr_frame;
   WebPIterator prev_frame;
   WebPChunkIterator iccp;
+  int viewport_width, viewport_height;
 } kParams;
 
 static void ClearPreviousPic(void) {
@@ -82,6 +89,16 @@ static void ClearParams(void) {
   kParams.dmux = NULL;
 }
 
+// Sets the previous frame to the dimensions of the canvas and has it dispose
+// to background to cause the canvas to be cleared.
+static void ClearPreviousFrame(void) {
+  WebPIterator* const prev = &kParams.prev_frame;
+  prev->width = kParams.canvas_width;
+  prev->height = kParams.canvas_height;
+  prev->x_offset = prev->y_offset = 0;
+  prev->dispose_method = WEBP_MUX_DISPOSE_BACKGROUND;
+}
+
 // -----------------------------------------------------------------------------
 // Color profile handling
 static int ApplyColorProfile(const WebPData* const profile,
@@ -181,6 +198,8 @@ static void decode_callback(int what) {
         if (WebPDemuxGetFrame(kParams.dmux, 1, curr)) {
           --kParams.loop_count;
           kParams.done = (kParams.loop_count == 0);
+          if (kParams.done) return;
+          ClearPreviousFrame();
         } else {
           kParams.decoding_error = 1;
           kParams.done = 1;
@@ -188,6 +207,11 @@ static void decode_callback(int what) {
         }
       }
       duration = curr->duration;
+      // Behavior copied from Chrome, cf:
+      // https://cs.chromium.org/chromium/src/third_party/WebKit/Source/
+      // platform/graphics/DeferredImageDecoder.cpp?
+      // rcl=b4c33049f096cd283f32be9a58b9a9e768227c26&l=246
+      if (duration <= 10) duration = 100;
     }
     if (!Decode()) {
       kParams.decoding_error = 1;
@@ -203,6 +227,9 @@ static void decode_callback(int what) {
 // Callbacks
 
 static void HandleKey(unsigned char key, int pos_x, int pos_y) {
+  // Note: rescaling the window or toggling some features during an animation
+  // generates visual artifacts. This is not fixed because refreshing the frame
+  // may require rendering the whole animation from start till current frame.
   (void)pos_x;
   (void)pos_y;
   if (key == 'q' || key == 'Q' || key == 27 /* Esc */) {
@@ -230,20 +257,31 @@ static void HandleKey(unsigned char key, int pos_x, int pos_y) {
         glutPostRedisplay();
       }
     }
+  } else if (key == 'b') {
+    kParams.draw_anim_background_color = 1 - kParams.draw_anim_background_color;
+    if (!kParams.has_animation) ClearPreviousFrame();
+    glutPostRedisplay();
   } else if (key == 'i') {
     kParams.print_info = 1 - kParams.print_info;
+    if (!kParams.has_animation) ClearPreviousFrame();
+    glutPostRedisplay();
+  } else if (key == 'd') {
+    kParams.only_deltas = 1 - kParams.only_deltas;
     glutPostRedisplay();
   }
 }
 
 static void HandleReshape(int width, int height) {
-  // TODO(skal): proper handling of resize, esp. for large pictures.
-  // + key control of the zoom.
+  // Note: reshape doesn't preserve aspect ratio, and might
+  // be handling larger-than-screen pictures incorrectly.
   glViewport(0, 0, width, height);
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
+  kParams.viewport_width = width;
+  kParams.viewport_height = height;
+  if (!kParams.has_animation) ClearPreviousFrame();
 }
 
 static void PrintString(const char* const text) {
@@ -254,8 +292,21 @@ static void PrintString(const char* const text) {
   }
 }
 
+static void PrintStringW(const char* const text) {
+#if defined(_WIN32) && defined(_UNICODE)
+  void* const font = GLUT_BITMAP_9_BY_15;
+  const W_CHAR* const wtext = (const W_CHAR*)text;
+  int i;
+  for (i = 0; wtext[i]; ++i) {
+    glutBitmapCharacter(font, wtext[i]);
+  }
+#else
+  PrintString(text);
+#endif
+}
+
 static float GetColorf(uint32_t color, int shift) {
-  return (color >> shift) / 255.f;
+  return ((color >> shift) & 0xff) / 255.f;
 }
 
 static void DrawCheckerBoard(void) {
@@ -278,6 +329,43 @@ static void DrawCheckerBoard(void) {
   glPopMatrix();
 }
 
+static void DrawBackground(void) {
+  // Whole window cleared with clear color, checkerboard rendered on top of it.
+  glClear(GL_COLOR_BUFFER_BIT);
+  DrawCheckerBoard();
+
+  // ANIM background color rendered (blend) on top. Default is white for still
+  // images (without ANIM chunk). glClear() can't be used for that (no blend).
+  if (kParams.draw_anim_background_color) {
+    glPushMatrix();
+    glLoadIdentity();
+    glColor4f(GetColorf(kParams.bg_color, 16),  // BGRA from spec
+              GetColorf(kParams.bg_color, 8),
+              GetColorf(kParams.bg_color, 0),
+              GetColorf(kParams.bg_color, 24));
+    glRecti(-1, -1, +1, +1);
+    glPopMatrix();
+  }
+}
+
+// Draw background in a scissored rectangle.
+static void DrawBackgroundScissored(int window_x, int window_y, int frame_w,
+                                    int frame_h) {
+  // Only update the requested area, not the whole canvas.
+  window_x = window_x * kParams.viewport_width / kParams.canvas_width;
+  window_y = window_y * kParams.viewport_height / kParams.canvas_height;
+  frame_w = frame_w * kParams.viewport_width / kParams.canvas_width;
+  frame_h = frame_h * kParams.viewport_height / kParams.canvas_height;
+
+  // glScissor() takes window coordinates (0,0 at bottom left).
+  window_y = kParams.viewport_height - window_y - frame_h;
+
+  glEnable(GL_SCISSOR_TEST);
+  glScissor(window_x, window_y, frame_w, frame_h);
+  DrawBackground();
+  glDisable(GL_SCISSOR_TEST);
+}
+
 static void HandleDisplay(void) {
   const WebPDecBuffer* const pic = kParams.pic;
   const WebPIterator* const curr = &kParams.curr_frame;
@@ -285,37 +373,30 @@ static void HandleDisplay(void) {
   GLfloat xoff, yoff;
   if (pic == NULL) return;
   glPushMatrix();
-  glPixelZoom(1, -1);
+  glPixelZoom((GLfloat)(+1. / kParams.canvas_width * kParams.viewport_width),
+              (GLfloat)(-1. / kParams.canvas_height * kParams.viewport_height));
   xoff = (GLfloat)(2. * curr->x_offset / kParams.canvas_width);
   yoff = (GLfloat)(2. * curr->y_offset / kParams.canvas_height);
   glRasterPos2f(-1.f + xoff, 1.f - yoff);
   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
   glPixelStorei(GL_UNPACK_ROW_LENGTH, pic->u.RGBA.stride / 4);
 
-  if (prev->dispose_method == WEBP_MUX_DISPOSE_BACKGROUND ||
-      curr->blend_method == WEBP_MUX_NO_BLEND) {
-    // TODO(later): these offsets and those above should factor in window size.
-    //              they will be incorrect if the window is resized.
-    // glScissor() takes window coordinates (0,0 at bottom left).
-    int window_x, window_y;
+  if (kParams.only_deltas) {
+    DrawBackground();
+  } else {
+    // The rectangle of the previous frame might be different than the current
+    // frame, so we may need to DrawBackgroundScissored for both.
     if (prev->dispose_method == WEBP_MUX_DISPOSE_BACKGROUND) {
       // Clear the previous frame rectangle.
-      window_x = prev->x_offset;
-      window_y = kParams.canvas_height - prev->y_offset - prev->height;
-    } else {  // curr->blend_method == WEBP_MUX_NO_BLEND.
-      // We simulate no-blending behavior by first clearing the current frame
-      // rectangle (to a checker-board) and then alpha-blending against it.
-      window_x = curr->x_offset;
-      window_y = kParams.canvas_height - curr->y_offset - curr->height;
+      DrawBackgroundScissored(prev->x_offset, prev->y_offset, prev->width,
+                              prev->height);
+    }
+    if (curr->blend_method == WEBP_MUX_NO_BLEND) {
+      // We simulate no-blending behavior by first clearing the current frame
+      // rectangle and then alpha-blending against it.
+      DrawBackgroundScissored(curr->x_offset, curr->y_offset, curr->width,
+                              curr->height);
     }
-    glEnable(GL_SCISSOR_TEST);
-    // Only update the requested area, not the whole canvas.
-    glScissor(window_x, window_y, prev->width, prev->height);
-
-    glClear(GL_COLOR_BUFFER_BIT);  // use clear color
-    DrawCheckerBoard();
-
-    glDisable(GL_SCISSOR_TEST);
   }
 
   *prev = *curr;
@@ -328,7 +409,7 @@ static void HandleDisplay(void) {
 
     glColor4f(0.90f, 0.0f, 0.90f, 1.0f);
     glRasterPos2f(-0.95f, 0.90f);
-    PrintString(kParams.file_name);
+    PrintStringW(kParams.file_name);
 
     snprintf(tmp, sizeof(tmp), "Dimension:%d x %d", pic->width, pic->height);
     glColor4f(0.90f, 0.0f, 0.90f, 1.0f);
@@ -342,77 +423,110 @@ static void HandleDisplay(void) {
     }
   }
   glPopMatrix();
+#if defined(__APPLE__) || defined(_WIN32)
   glFlush();
+#else
+  glutSwapBuffers();
+#endif
 }
 
 static void StartDisplay(void) {
-  const int width = kParams.canvas_width;
-  const int height = kParams.canvas_height;
+  int width = kParams.canvas_width;
+  int height = kParams.canvas_height;
+  int screen_width, screen_height;
+  // TODO(webp:365) GLUT_DOUBLE results in flickering / old frames to be
+  // partially displayed with animated webp + alpha.
+#if defined(__APPLE__) || defined(_WIN32)
   glutInitDisplayMode(GLUT_RGBA);
+#else
+  glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA);
+#endif
+  screen_width = glutGet(GLUT_SCREEN_WIDTH);
+  screen_height = glutGet(GLUT_SCREEN_HEIGHT);
+  if (width > screen_width || height > screen_height) {
+    if (width > screen_width) {
+      height = (height * screen_width + width - 1) / width;
+      width = screen_width;
+    }
+    if (height > screen_height) {
+      width = (width * screen_height + height - 1) / height;
+      height = screen_height;
+    }
+  }
   glutInitWindowSize(width, height);
   glutCreateWindow("WebP viewer");
   glutDisplayFunc(HandleDisplay);
+  glutReshapeFunc(HandleReshape);
   glutIdleFunc(NULL);
   glutKeyboardFunc(HandleKey);
   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
   glEnable(GL_BLEND);
-  glClearColor(GetColorf(kParams.bg_color, 0),
-               GetColorf(kParams.bg_color, 8),
-               GetColorf(kParams.bg_color, 16),
-               GetColorf(kParams.bg_color, 24));
-  HandleReshape(width, height);
-  glClear(GL_COLOR_BUFFER_BIT);
-  DrawCheckerBoard();
+  glClearColor(0, 0, 0, 0);  // window will be cleared to black (no blend)
+  DrawBackground();
 }
 
 //------------------------------------------------------------------------------
 // Main
 
 static void Help(void) {
-  printf("Usage: vwebp in_file [options]\n\n"
-         "Decodes the WebP image file and visualize it using OpenGL\n"
-         "Options are:\n"
-         "  -version  .... print version number and exit.\n"
-         "  -noicc ....... don't use the icc profile if present.\n"
-         "  -nofancy ..... don't use the fancy YUV420 upscaler.\n"
-         "  -nofilter .... disable in-loop filtering.\n"
-         "  -dither <int>  dithering strength (0..100). Default=50.\n"
-         "  -mt .......... use multi-threading.\n"
-         "  -info ........ print info.\n"
-         "  -h     ....... this help message.\n"
-         "\n"
-         "Keyboard shortcuts:\n"
-         "  'c' ................ toggle use of color profile.\n"
-         "  'i' ................ overlay file information.\n"
-         "  'q' / 'Q' / ESC .... quit.\n"
-        );
+  printf(
+      "Usage: vwebp in_file [options]\n\n"
+      "Decodes the WebP image file and visualize it using OpenGL\n"
+      "Options are:\n"
+      "  -version ..... print version number and exit\n"
+      "  -noicc ....... don't use the icc profile if present\n"
+      "  -nofancy ..... don't use the fancy YUV420 upscaler\n"
+      "  -nofilter .... disable in-loop filtering\n"
+      "  -dither <int>  dithering strength (0..100), default=50\n"
+      "  -noalphadither disable alpha plane dithering\n"
+      "  -usebgcolor .. display background color\n"
+      "  -mt .......... use multi-threading\n"
+      "  -info ........ print info\n"
+      "  -h ........... this help message\n"
+      "\n"
+      "Keyboard shortcuts:\n"
+      "  'c' ................ toggle use of color profile\n"
+      "  'b' ................ toggle background color display\n"
+      "  'i' ................ overlay file information\n"
+      "  'd' ................ disable blending & disposal (debug)\n"
+      "  'q' / 'Q' / ESC .... quit\n");
 }
 
-int main(int argc, char *argv[]) {
+int main(int argc, char* argv[]) {
   int c;
   WebPDecoderConfig* const config = &kParams.config;
   WebPIterator* const curr = &kParams.curr_frame;
-  WebPIterator* const prev = &kParams.prev_frame;
+
+  INIT_WARGV(argc, argv);
 
   if (!WebPInitDecoderConfig(config)) {
     fprintf(stderr, "Library version mismatch!\n");
-    return -1;
+    FREE_WARGV_AND_RETURN(-1);
   }
   config->options.dithering_strength = 50;
+  config->options.alpha_dithering_strength = 100;
   kParams.use_color_profile = 1;
+  // Background color hidden by default to see transparent areas.
+  kParams.draw_anim_background_color = 0;
 
   for (c = 1; c < argc; ++c) {
+    int parse_error = 0;
     if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
       Help();
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else if (!strcmp(argv[c], "-noicc")) {
       kParams.use_color_profile = 0;
     } else if (!strcmp(argv[c], "-nofancy")) {
       config->options.no_fancy_upsampling = 1;
     } else if (!strcmp(argv[c], "-nofilter")) {
       config->options.bypass_filtering = 1;
+    } else if (!strcmp(argv[c], "-noalphadither")) {
+      config->options.alpha_dithering_strength = 0;
+    } else if (!strcmp(argv[c], "-usebgcolor")) {
+      kParams.draw_anim_background_color = 1;
     } else if (!strcmp(argv[c], "-dither") && c + 1 < argc) {
-      config->options.dithering_strength = strtol(argv[++c], NULL, 0);
+      config->options.dithering_strength =
+          ExUtilGetInt(argv[++c], 0, &parse_error);
     } else if (!strcmp(argv[c], "-info")) {
       kParams.print_info = 1;
     } else if (!strcmp(argv[c], "-version")) {
@@ -422,29 +536,34 @@ int main(int argc, char *argv[]) {
              (dec_version >> 16) & 0xff, (dec_version >> 8) & 0xff,
              dec_version & 0xff, (dmux_version >> 16) & 0xff,
              (dmux_version >> 8) & 0xff, dmux_version & 0xff);
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else if (!strcmp(argv[c], "-mt")) {
       config->options.use_threads = 1;
     } else if (!strcmp(argv[c], "--")) {
-      if (c < argc - 1) kParams.file_name = argv[++c];
+      if (c < argc - 1) kParams.file_name = (const char*)GET_WARGV(argv, ++c);
       break;
     } else if (argv[c][0] == '-') {
       printf("Unknown option '%s'\n", argv[c]);
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(-1);
     } else {
-      kParams.file_name = argv[c];
+      kParams.file_name = (const char*)GET_WARGV(argv, c);
+    }
+
+    if (parse_error) {
+      Help();
+      FREE_WARGV_AND_RETURN(-1);
     }
   }
 
   if (kParams.file_name == NULL) {
     printf("missing input file!!\n");
     Help();
-    return 0;
+    FREE_WARGV_AND_RETURN(0);
   }
 
-  if (!ExUtilReadFile(kParams.file_name,
-                      &kParams.data.bytes, &kParams.data.size)) {
+  if (!ImgIoUtilReadFile(kParams.file_name,
+                         &kParams.data.bytes, &kParams.data.size)) {
     goto Error;
   }
 
@@ -459,20 +578,13 @@ int main(int argc, char *argv[]) {
     goto Error;
   }
 
-  if (WebPDemuxGetI(kParams.dmux, WEBP_FF_FORMAT_FLAGS) & FRAGMENTS_FLAG) {
-    fprintf(stderr, "Image fragments are not supported for now!\n");
-    goto Error;
-  }
   kParams.canvas_width = WebPDemuxGetI(kParams.dmux, WEBP_FF_CANVAS_WIDTH);
   kParams.canvas_height = WebPDemuxGetI(kParams.dmux, WEBP_FF_CANVAS_HEIGHT);
   if (kParams.print_info) {
     printf("Canvas: %d x %d\n", kParams.canvas_width, kParams.canvas_height);
   }
 
-  prev->width = kParams.canvas_width;
-  prev->height = kParams.canvas_height;
-  prev->x_offset = prev->y_offset = 0;
-  prev->dispose_method = WEBP_MUX_DISPOSE_BACKGROUND;
+  ClearPreviousFrame();
 
   memset(&kParams.iccp, 0, sizeof(kParams.iccp));
   kParams.has_color_profile =
@@ -504,6 +616,12 @@ int main(int argc, char *argv[]) {
   WebPDemuxGetFrame(kParams.dmux, 0, curr);
   if (kParams.loop_count) ++kParams.loop_count;
 
+#if defined(__unix__) || defined(__CYGWIN__)
+  // Work around GLUT compositor bug.
+  // https://bugs.launchpad.net/ubuntu/+source/freeglut/+bug/369891
+  setenv("XLIB_SKIP_ARGB_VISUALS", "1", 1);
+#endif
+
   // Start display (and timer)
   glutInit(&argc, argv);
 #ifdef FREEGLUT
@@ -516,16 +634,16 @@ int main(int argc, char *argv[]) {
 
   // Should only be reached when using FREEGLUT:
   ClearParams();
-  return 0;
+  FREE_WARGV_AND_RETURN(0);
 
  Error:
   ClearParams();
-  return -1;
+  FREE_WARGV_AND_RETURN(-1);
 }
 
 #else   // !WEBP_HAVE_GL
 
-int main(int argc, const char *argv[]) {
+int main(int argc, const char* argv[]) {
   fprintf(stderr, "OpenGL support not enabled in %s.\n", argv[0]);
   (void)argc;
   return 0;

extras/Makefile.am

@@ -0,0 +1,44 @@
+AM_CPPFLAGS += -I$(top_builddir) -I$(top_srcdir)
+AM_CPPFLAGS += -I$(top_builddir)/src -I$(top_srcdir)/src
+noinst_LTLIBRARIES = libwebpextras.la
+
+noinst_HEADERS =
+noinst_HEADERS += ../src/webp/types.h
+
+libwebpextras_la_SOURCES =
+libwebpextras_la_SOURCES += extras.c extras.h quality_estimate.c
+
+libwebpextras_la_CPPFLAGS = $(AM_CPPFLAGS)
+libwebpextras_la_LDFLAGS = -lm
+libwebpextras_la_LIBADD = ../src/libwebp.la
+
+noinst_PROGRAMS =
+noinst_PROGRAMS += webp_quality
+if BUILD_DEMUX
+  noinst_PROGRAMS += get_disto
+endif
+if BUILD_VWEBP_SDL
+  noinst_PROGRAMS += vwebp_sdl
+endif
+
+get_disto_SOURCES  = get_disto.c
+get_disto_CPPFLAGS = $(AM_CPPFLAGS)
+get_disto_LDADD =
+get_disto_LDADD += ../imageio/libimageio_util.la
+get_disto_LDADD += ../imageio/libimagedec.la
+get_disto_LDADD += ../src/libwebp.la
+get_disto_LDADD += $(PNG_LIBS) $(JPEG_LIBS) $(TIFF_LIBS)
+
+webp_quality_SOURCES  = webp_quality.c
+webp_quality_CPPFLAGS = $(AM_CPPFLAGS)
+webp_quality_LDADD =
+webp_quality_LDADD += ../imageio/libimageio_util.la
+webp_quality_LDADD += libwebpextras.la
+webp_quality_LDADD += ../src/libwebp.la
+
+vwebp_sdl_SOURCES  = vwebp_sdl.c webp_to_sdl.c webp_to_sdl.h
+vwebp_sdl_CPPFLAGS = $(AM_CPPFLAGS) $(SDL_INCLUDES)
+vwebp_sdl_LDADD =
+vwebp_sdl_LDADD += ../imageio/libimageio_util.la
+vwebp_sdl_LDADD += ../src/libwebp.la
+vwebp_sdl_LDADD += $(SDL_LIBS)

extras/extras.c

@@ -0,0 +1,162 @@
+// Copyright 2015 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  Additional WebP utilities.
+//
+
+#include "extras/extras.h"
+#include "webp/format_constants.h"
+#include "src/dsp/dsp.h"
+
+#include <assert.h>
+#include <string.h>
+
+#define XTRA_MAJ_VERSION 1
+#define XTRA_MIN_VERSION 2
+#define XTRA_REV_VERSION 3
+
+//------------------------------------------------------------------------------
+
+int WebPGetExtrasVersion(void) {
+  return (XTRA_MAJ_VERSION << 16) | (XTRA_MIN_VERSION << 8) | XTRA_REV_VERSION;
+}
+
+//------------------------------------------------------------------------------
+
+int WebPImportGray(const uint8_t* gray_data, WebPPicture* pic) {
+  int y, width, uv_width;
+  if (pic == NULL || gray_data == NULL) return 0;
+  pic->colorspace = WEBP_YUV420;
+  if (!WebPPictureAlloc(pic)) return 0;
+  width = pic->width;
+  uv_width = (width + 1) >> 1;
+  for (y = 0; y < pic->height; ++y) {
+    memcpy(pic->y + y * pic->y_stride, gray_data, width);
+    gray_data += width;    // <- we could use some 'data_stride' here if needed
+    if ((y & 1) == 0) {
+      memset(pic->u + (y >> 1) * pic->uv_stride, 128, uv_width);
+      memset(pic->v + (y >> 1) * pic->uv_stride, 128, uv_width);
+    }
+  }
+  return 1;
+}
+
+int WebPImportRGB565(const uint8_t* rgb565, WebPPicture* pic) {
+  int x, y;
+  uint32_t* dst;
+  if (pic == NULL || rgb565 == NULL) return 0;
+  pic->colorspace = WEBP_YUV420;
+  pic->use_argb = 1;
+  if (!WebPPictureAlloc(pic)) return 0;
+  dst = pic->argb;
+  for (y = 0; y < pic->height; ++y) {
+    const int width = pic->width;
+    for (x = 0; x < width; ++x) {
+#if defined(WEBP_SWAP_16BIT_CSP) && (WEBP_SWAP_16BIT_CSP == 1)
+      const uint32_t rg = rgb565[2 * x + 1];
+      const uint32_t gb = rgb565[2 * x + 0];
+#else
+      const uint32_t rg = rgb565[2 * x + 0];
+      const uint32_t gb = rgb565[2 * x + 1];
+#endif
+      uint32_t r = rg & 0xf8;
+      uint32_t g = ((rg << 5) | (gb >> 3)) & 0xfc;
+      uint32_t b = (gb << 5);
+      // dithering
+      r = r | (r >> 5);
+      g = g | (g >> 6);
+      b = b | (b >> 5);
+      dst[x] = (0xffu << 24) | (r << 16) | (g << 8) | b;
+    }
+    rgb565 += 2 * width;
+    dst += pic->argb_stride;
+  }
+  return 1;
+}
+
+int WebPImportRGB4444(const uint8_t* rgb4444, WebPPicture* pic) {
+  int x, y;
+  uint32_t* dst;
+  if (pic == NULL || rgb4444 == NULL) return 0;
+  pic->colorspace = WEBP_YUV420;
+  pic->use_argb = 1;
+  if (!WebPPictureAlloc(pic)) return 0;
+  dst = pic->argb;
+  for (y = 0; y < pic->height; ++y) {
+    const int width = pic->width;
+    for (x = 0; x < width; ++x) {
+#if defined(WEBP_SWAP_16BIT_CSP) && (WEBP_SWAP_16BIT_CSP == 1)
+      const uint32_t rg = rgb4444[2 * x + 1];
+      const uint32_t ba = rgb4444[2 * x + 0];
+#else
+      const uint32_t rg = rgb4444[2 * x + 0];
+      const uint32_t ba = rgb4444[2 * x + 1];
+#endif
+      uint32_t r = rg & 0xf0;
+      uint32_t g = (rg << 4);
+      uint32_t b = (ba & 0xf0);
+      uint32_t a = (ba << 4);
+      // dithering
+      r = r | (r >> 4);
+      g = g | (g >> 4);
+      b = b | (b >> 4);
+      a = a | (a >> 4);
+      dst[x] = (a << 24) | (r << 16) | (g << 8) | b;
+    }
+    rgb4444 += 2 * width;
+    dst += pic->argb_stride;
+  }
+  return 1;
+}
+
+int WebPImportColorMappedARGB(const uint8_t* indexed, int indexed_stride,
+                              const uint32_t palette[], int palette_size,
+                              WebPPicture* pic) {
+  int x, y;
+  uint32_t* dst;
+  // 256 as the input buffer is uint8_t.
+  assert(MAX_PALETTE_SIZE <= 256);
+  if (pic == NULL || indexed == NULL || indexed_stride < pic->width ||
+      palette == NULL || palette_size > MAX_PALETTE_SIZE || palette_size <= 0) {
+    return 0;
+  }
+  pic->use_argb = 1;
+  if (!WebPPictureAlloc(pic)) return 0;
+  dst = pic->argb;
+  for (y = 0; y < pic->height; ++y) {
+    for (x = 0; x < pic->width; ++x) {
+      // Make sure we are within the palette.
+      if (indexed[x] >= palette_size) {
+        WebPPictureFree(pic);
+        return 0;
+      }
+      dst[x] = palette[indexed[x]];
+    }
+    indexed += indexed_stride;
+    dst += pic->argb_stride;
+  }
+  return 1;
+}
+
+//------------------------------------------------------------------------------
+
+int WebPUnmultiplyARGB(WebPPicture* pic) {
+  int y;
+  uint32_t* dst;
+  if (pic == NULL || pic->use_argb != 1 || pic->argb == NULL) return 0;
+  WebPInitAlphaProcessing();
+  dst = pic->argb;
+  for (y = 0; y < pic->height; ++y) {
+    WebPMultARGBRow(dst, pic->width, /*inverse=*/1);
+    dst += pic->argb_stride;
+  }
+  return 1;
+}
+
+//------------------------------------------------------------------------------

extras/extras.h

@@ -0,0 +1,77 @@
+// Copyright 2015 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+
+#ifndef WEBP_EXTRAS_EXTRAS_H_
+#define WEBP_EXTRAS_EXTRAS_H_
+
+#include "webp/types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "webp/encode.h"
+
+#define WEBP_EXTRAS_ABI_VERSION 0x0002    // MAJOR(8b) + MINOR(8b)
+
+//------------------------------------------------------------------------------
+
+// Returns the version number of the extras library, packed in hexadecimal using
+// 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
+WEBP_EXTERN int WebPGetExtrasVersion(void);
+
+//------------------------------------------------------------------------------
+// Ad-hoc colorspace importers.
+
+// Import luma sample (gray scale image) into 'picture'. The 'picture'
+// width and height must be set prior to calling this function.
+WEBP_EXTERN int WebPImportGray(const uint8_t* gray, WebPPicture* picture);
+
+// Import rgb sample in RGB565 packed format into 'picture'. The 'picture'
+// width and height must be set prior to calling this function.
+WEBP_EXTERN int WebPImportRGB565(const uint8_t* rgb565, WebPPicture* pic);
+
+// Import rgb sample in RGB4444 packed format into 'picture'. The 'picture'
+// width and height must be set prior to calling this function.
+WEBP_EXTERN int WebPImportRGB4444(const uint8_t* rgb4444, WebPPicture* pic);
+
+// Import a color mapped image. The number of colors is less or equal to
+// MAX_PALETTE_SIZE. 'pic' must have been initialized. Its content, if any,
+// will be discarded. Returns 'false' in case of error, or if indexed[] contains
+// invalid indices.
+WEBP_EXTERN int
+WebPImportColorMappedARGB(const uint8_t* indexed, int indexed_stride,
+                          const uint32_t palette[], int palette_size,
+                          WebPPicture* pic);
+
+// Convert the ARGB content of 'pic' from associated to unassociated.
+// 'pic' can be for instance the result of calling of some WebPPictureImportXXX
+// functions, with pic->use_argb set to 'true'. It is assumed (and not checked)
+// that the pre-multiplied r/g/b values as less or equal than the alpha value.
+// Return false in case of error (invalid parameter, ...).
+WEBP_EXTERN int WebPUnmultiplyARGB(WebPPicture* pic);
+
+//------------------------------------------------------------------------------
+
+// Parse a bitstream, search for VP8 (lossy) header and report a
+// rough estimation of the quality factor used for compressing the bitstream.
+// If the bitstream is in lossless format, the special value '101' is returned.
+// Otherwise (lossy bitstream), the returned value is in the range [0..100].
+// Any error (invalid bitstream, animated WebP, incomplete header, etc.)
+// will return a value of -1.
+WEBP_EXTERN int VP8EstimateQuality(const uint8_t* const data, size_t size);
+
+//------------------------------------------------------------------------------
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_EXTRAS_EXTRAS_H_

extras/get_disto.c

@@ -0,0 +1,356 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Simple tool to load two webp/png/jpg/tiff files and compute PSNR/SSIM.
+// This is mostly a wrapper around WebPPictureDistortion().
+//
+/*
+ gcc -o get_disto get_disto.c -O3 -I../ -L../examples -L../imageio \
+    -lexample_util -limageio_util -limagedec -lwebp -L/opt/local/lib \
+    -lpng -lz -ljpeg -ltiff -lm -lpthread
+*/
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "webp/encode.h"
+#include "imageio/image_dec.h"
+#include "imageio/imageio_util.h"
+#include "../examples/unicode.h"
+
+static size_t ReadPicture(const char* const filename, WebPPicture* const pic,
+                          int keep_alpha) {
+  const uint8_t* data = NULL;
+  size_t data_size = 0;
+  WebPImageReader reader = NULL;
+  int ok = ImgIoUtilReadFile(filename, &data, &data_size);
+  if (!ok) goto End;
+
+  pic->use_argb = 1;  // force ARGB
+
+#ifdef HAVE_WINCODEC_H
+  // Try to decode the file using WIC falling back to the other readers for
+  // e.g., WebP.
+  ok = ReadPictureWithWIC(filename, pic, keep_alpha, NULL);
+  if (ok) goto End;
+#endif
+  reader = WebPGuessImageReader(data, data_size);
+  ok = reader(data, data_size, pic, keep_alpha, NULL);
+
+ End:
+  if (!ok) {
+    WFPRINTF(stderr, "Error! Could not process file %s\n",
+             (const W_CHAR*)filename);
+  }
+  free((void*)data);
+  return ok ? data_size : 0;
+}
+
+static void RescalePlane(uint8_t* plane, int width, int height,
+                         int x_stride, int y_stride, int max) {
+  const uint32_t factor = (max > 0) ? (255u << 16) / max : 0;
+  int x, y;
+  for (y = 0; y < height; ++y) {
+    uint8_t* const ptr = plane + y * y_stride;
+    for (x = 0; x < width * x_stride; x += x_stride) {
+      const uint32_t diff = (ptr[x] * factor + (1 << 15)) >> 16;
+      ptr[x] = diff;
+    }
+  }
+}
+
+// Return the max absolute difference.
+static int DiffScaleChannel(uint8_t* src1, int stride1,
+                            const uint8_t* src2, int stride2,
+                            int x_stride, int w, int h, int do_scaling) {
+  int x, y;
+  int max = 0;
+  for (y = 0; y < h; ++y) {
+    uint8_t* const ptr1 = src1 + y * stride1;
+    const uint8_t* const ptr2 = src2 + y * stride2;
+    for (x = 0; x < w * x_stride; x += x_stride) {
+      const int diff = abs(ptr1[x] - ptr2[x]);
+      if (diff > max) max = diff;
+      ptr1[x] = diff;
+    }
+  }
+
+  if (do_scaling) RescalePlane(src1, w, h, x_stride, stride1, max);
+  return max;
+}
+
+//------------------------------------------------------------------------------
+// SSIM calculation. We re-implement these functions here, out of dsp/, to avoid
+// breaking the library's hidden visibility. This code duplication avoids the
+// bigger annoyance of having to open up internal details of libdsp...
+
+#define SSIM_KERNEL 3   // total size of the kernel: 2 * SSIM_KERNEL + 1
+
+// struct for accumulating statistical moments
+typedef struct {
+  uint32_t w;              // sum(w_i) : sum of weights
+  uint32_t xm, ym;         // sum(w_i * x_i), sum(w_i * y_i)
+  uint32_t xxm, xym, yym;  // sum(w_i * x_i * x_i), etc.
+} DistoStats;
+
+// hat-shaped filter. Sum of coefficients is equal to 16.
+static const uint32_t kWeight[2 * SSIM_KERNEL + 1] = { 1, 2, 3, 4, 3, 2, 1 };
+
+static WEBP_INLINE double SSIMCalculation(const DistoStats* const stats) {
+  const uint32_t N = stats->w;
+  const uint32_t w2 =  N * N;
+  const uint32_t C1 = 20 * w2;
+  const uint32_t C2 = 60 * w2;
+  const uint32_t C3 = 8 * 8 * w2;   // 'dark' limit ~= 6
+  const uint64_t xmxm = (uint64_t)stats->xm * stats->xm;
+  const uint64_t ymym = (uint64_t)stats->ym * stats->ym;
+  if (xmxm + ymym >= C3) {
+    const int64_t xmym = (int64_t)stats->xm * stats->ym;
+    const int64_t sxy = (int64_t)stats->xym * N - xmym;    // can be negative
+    const uint64_t sxx = (uint64_t)stats->xxm * N - xmxm;
+    const uint64_t syy = (uint64_t)stats->yym * N - ymym;
+    // we descale by 8 to prevent overflow during the fnum/fden multiply.
+    const uint64_t num_S = (2 * (uint64_t)(sxy < 0 ? 0 : sxy) + C2) >> 8;
+    const uint64_t den_S = (sxx + syy + C2) >> 8;
+    const uint64_t fnum = (2 * xmym + C1) * num_S;
+    const uint64_t fden = (xmxm + ymym + C1) * den_S;
+    const double r = (double)fnum / fden;
+    assert(r >= 0. && r <= 1.0);
+    return r;
+  }
+  return 1.;   // area is too dark to contribute meaningfully
+}
+
+static double SSIMGetClipped(const uint8_t* src1, int stride1,
+                             const uint8_t* src2, int stride2,
+                             int xo, int yo, int W, int H) {
+  DistoStats stats = { 0, 0, 0, 0, 0, 0 };
+  const int ymin = (yo - SSIM_KERNEL < 0) ? 0 : yo - SSIM_KERNEL;
+  const int ymax = (yo + SSIM_KERNEL > H - 1) ? H - 1 : yo + SSIM_KERNEL;
+  const int xmin = (xo - SSIM_KERNEL < 0) ? 0 : xo - SSIM_KERNEL;
+  const int xmax = (xo + SSIM_KERNEL > W - 1) ? W - 1 : xo + SSIM_KERNEL;
+  int x, y;
+  src1 += ymin * stride1;
+  src2 += ymin * stride2;
+  for (y = ymin; y <= ymax; ++y, src1 += stride1, src2 += stride2) {
+    for (x = xmin; x <= xmax; ++x) {
+      const uint32_t w = kWeight[SSIM_KERNEL + x - xo]
+                       * kWeight[SSIM_KERNEL + y - yo];
+      const uint32_t s1 = src1[x];
+      const uint32_t s2 = src2[x];
+      stats.w   += w;
+      stats.xm  += w * s1;
+      stats.ym  += w * s2;
+      stats.xxm += w * s1 * s1;
+      stats.xym += w * s1 * s2;
+      stats.yym += w * s2 * s2;
+    }
+  }
+  return SSIMCalculation(&stats);
+}
+
+// Compute SSIM-score map. Return -1 in case of error, max diff otherwise.
+static int SSIMScaleChannel(uint8_t* src1, int stride1,
+                            const uint8_t* src2, int stride2,
+                            int x_stride, int w, int h, int do_scaling) {
+  int x, y;
+  int max = 0;
+  uint8_t* const plane1 = (uint8_t*)malloc(2 * w * h * sizeof(*plane1));
+  uint8_t* const plane2 = plane1 + w * h;
+  if (plane1 == NULL) return -1;
+
+  // extract plane
+  for (y = 0; y < h; ++y) {
+    for (x = 0; x < w; ++x) {
+      plane1[x + y * w] = src1[x * x_stride + y * stride1];
+      plane2[x + y * w] = src2[x * x_stride + y * stride2];
+    }
+  }
+  for (y = 0; y < h; ++y) {
+    for (x = 0; x < w; ++x) {
+      const double ssim = SSIMGetClipped(plane1, w, plane2, w, x, y, w, h);
+      int diff = (int)(255 * (1. - ssim));
+      if (diff < 0) {
+        diff = 0;
+      } else if (diff > max) {
+        max = diff;
+      }
+      src1[x * x_stride + y * stride1] = (diff > 255) ? 255u : (uint8_t)diff;
+    }
+  }
+  free(plane1);
+
+  if (do_scaling) RescalePlane(src1, w, h, x_stride, stride1, max);
+  return max;
+}
+
+// Convert an argb picture to luminance.
+static void ConvertToGray(WebPPicture* const pic) {
+  int x, y;
+  assert(pic != NULL);
+  assert(pic->use_argb);
+  for (y = 0; y < pic->height; ++y) {
+    uint32_t* const row = &pic->argb[y * pic->argb_stride];
+    for (x = 0; x < pic->width; ++x) {
+      const uint32_t argb = row[x];
+      const uint32_t r = (argb >> 16) & 0xff;
+      const uint32_t g = (argb >>  8) & 0xff;
+      const uint32_t b = (argb >>  0) & 0xff;
+      // We use BT.709 for converting to luminance.
+      const uint32_t Y = (uint32_t)(0.2126 * r + 0.7152 * g + 0.0722 * b + .5);
+      row[x] = (argb & 0xff000000u) | (Y * 0x010101u);
+    }
+  }
+}
+
+static void Help(void) {
+  fprintf(stderr,
+          "Usage: get_disto [-ssim][-psnr][-alpha] compressed.webp orig.webp\n"
+          "  -ssim ..... print SSIM distortion\n"
+          "  -psnr ..... print PSNR distortion (default)\n"
+          "  -alpha .... preserve alpha plane\n"
+          "  -h ........ this message\n"
+          "  -o <file> . save the diff map as a WebP lossless file\n"
+          "  -scale .... scale the difference map to fit [0..255] range\n"
+          "  -gray ..... use grayscale for difference map (-scale)\n"
+          "\nSupported input formats:\n  %s\n",
+          WebPGetEnabledInputFileFormats());
+}
+
+int main(int argc, const char* argv[]) {
+  WebPPicture pic1, pic2;
+  size_t size1 = 0, size2 = 0;
+  int ret = 1;
+  float disto[5];
+  int type = 0;
+  int c;
+  int help = 0;
+  int keep_alpha = 0;
+  int scale = 0;
+  int use_gray = 0;
+  const char* name1 = NULL;
+  const char* name2 = NULL;
+  const char* output = NULL;
+
+  INIT_WARGV(argc, argv);
+
+  if (!WebPPictureInit(&pic1) || !WebPPictureInit(&pic2)) {
+    fprintf(stderr, "Can't init pictures\n");
+    FREE_WARGV_AND_RETURN(1);
+  }
+
+  for (c = 1; c < argc; ++c) {
+    if (!strcmp(argv[c], "-ssim")) {
+      type = 1;
+    } else if (!strcmp(argv[c], "-psnr")) {
+      type = 0;
+    } else if (!strcmp(argv[c], "-alpha")) {
+      keep_alpha = 1;
+    } else if (!strcmp(argv[c], "-scale")) {
+      scale = 1;
+    } else if (!strcmp(argv[c], "-gray")) {
+      use_gray = 1;
+    } else if (!strcmp(argv[c], "-h")) {
+      help = 1;
+      ret = 0;
+    } else if (!strcmp(argv[c], "-o")) {
+      if (++c == argc) {
+        fprintf(stderr, "missing file name after %s option.\n", argv[c - 1]);
+        goto End;
+      }
+      output = (const char*)GET_WARGV(argv, c);
+    } else if (name1 == NULL) {
+      name1 = (const char*)GET_WARGV(argv, c);
+    } else {
+      name2 = (const char*)GET_WARGV(argv, c);
+    }
+  }
+  if (help || name1 == NULL || name2 == NULL) {
+    if (!help) {
+      fprintf(stderr, "Error: missing arguments.\n");
+    }
+    Help();
+    goto End;
+  }
+  size1 = ReadPicture(name1, &pic1, 1);
+  size2 = ReadPicture(name2, &pic2, 1);
+  if (size1 == 0 || size2 == 0) goto End;
+
+  if (!keep_alpha) {
+    WebPBlendAlpha(&pic1, 0x00000000);
+    WebPBlendAlpha(&pic2, 0x00000000);
+  }
+
+  if (!WebPPictureDistortion(&pic1, &pic2, type, disto)) {
+    fprintf(stderr, "Error while computing the distortion.\n");
+    goto End;
+  }
+  printf("%u %.2f    %.2f %.2f %.2f %.2f [ %.2f bpp ]\n",
+         (unsigned int)size1,
+         disto[4], disto[0], disto[1], disto[2], disto[3],
+         8.f * size1 / pic1.width / pic1.height);
+
+  if (output != NULL) {
+    uint8_t* data = NULL;
+    size_t data_size = 0;
+    if (pic1.use_argb != pic2.use_argb) {
+      fprintf(stderr, "Pictures are not in the same argb format. "
+                      "Can't save the difference map.\n");
+      goto End;
+    }
+    if (pic1.use_argb) {
+      int n;
+      fprintf(stderr, "max differences per channel: ");
+      for (n = 0; n < 3; ++n) {    // skip the alpha channel
+        const int range = (type == 1) ?
+          SSIMScaleChannel((uint8_t*)pic1.argb + n, pic1.argb_stride * 4,
+                           (const uint8_t*)pic2.argb + n, pic2.argb_stride * 4,
+                           4, pic1.width, pic1.height, scale) :
+          DiffScaleChannel((uint8_t*)pic1.argb + n, pic1.argb_stride * 4,
+                           (const uint8_t*)pic2.argb + n, pic2.argb_stride * 4,
+                           4, pic1.width, pic1.height, scale);
+        if (range < 0) fprintf(stderr, "\nError computing diff map\n");
+        fprintf(stderr, "[%d]", range);
+      }
+      fprintf(stderr, "\n");
+      if (use_gray) ConvertToGray(&pic1);
+    } else {
+      fprintf(stderr, "Can only compute the difference map in ARGB format.\n");
+      goto End;
+    }
+#if !defined(WEBP_REDUCE_CSP)
+    data_size = WebPEncodeLosslessBGRA((const uint8_t*)pic1.argb,
+                                       pic1.width, pic1.height,
+                                       pic1.argb_stride * 4,
+                                       &data);
+    if (data_size == 0) {
+      fprintf(stderr, "Error during lossless encoding.\n");
+      goto End;
+    }
+    ret = ImgIoUtilWriteFile(output, data, data_size) ? 0 : 1;
+    WebPFree(data);
+    if (ret) goto End;
+#else
+    (void)data;
+    (void)data_size;
+    fprintf(stderr, "Cannot save the difference map. Please recompile "
+                    "without the WEBP_REDUCE_CSP flag.\n");
+#endif  // WEBP_REDUCE_CSP
+  }
+  ret = 0;
+
+ End:
+  WebPPictureFree(&pic1);
+  WebPPictureFree(&pic2);
+  FREE_WARGV_AND_RETURN(ret);
+}

extras/quality_estimate.c

@@ -0,0 +1,129 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  VP8EstimateQuality(): rough encoding quality estimate
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "extras/extras.h"
+#include "webp/decode.h"
+
+#include <math.h>
+
+//------------------------------------------------------------------------------
+
+#define INVALID_BIT_POS (1ull << 63)
+
+// In most cases, we don't need to use a full arithmetic decoder, since
+// all the header's bits are written using a uniform probability of 128.
+// We can just parse the header as if it was bits (works in 99.999% cases).
+static WEBP_INLINE uint32_t GetBit(const uint8_t* const data, size_t nb,
+                                   uint64_t max_size, uint64_t* const bit_pos) {
+  uint32_t val = 0;
+  if (*bit_pos + nb <= 8 * max_size) {
+    while (nb-- > 0) {
+      const uint64_t p = (*bit_pos)++;
+      const int bit = !!(data[p >> 3] & (128 >> ((p & 7))));
+      val = (val << 1) | bit;
+    }
+  } else {
+    *bit_pos = INVALID_BIT_POS;
+  }
+  return val;
+}
+
+#define GET_BIT(n) GetBit(data, (n), size, &bit_pos)
+#define CONDITIONAL_SKIP(n) (GET_BIT(1) ? GET_BIT((n)) : 0)
+
+int VP8EstimateQuality(const uint8_t* const data, size_t size) {
+  size_t pos = 0;
+  uint64_t bit_pos;
+  uint64_t sig = 0x00;
+  int ok = 0;
+  int Q = -1;
+  WebPBitstreamFeatures features;
+
+  if (data == NULL) return -1;
+
+  if (WebPGetFeatures(data, size, &features) != VP8_STATUS_OK) {
+    return -1;   // invalid file
+  }
+  if (features.format == 2) return 101;  // lossless
+  if (features.format == 0 || features.has_animation) return -1;   // mixed
+
+  while (pos < size) {
+    sig = (sig >> 8) | ((uint64_t)data[pos++] << 40);
+    if ((sig >> 24) == 0x2a019dull) {
+      ok = 1;
+      break;
+    }
+  }
+  if (!ok) return -1;
+  if (pos + 4 > size) return -1;
+
+  // Skip main Header
+  // width  = (data[pos + 0] | (data[pos + 1] << 8)) & 0x3fff;
+  // height = (data[pos + 2] | (data[pos + 3] << 8)) & 0x3fff;
+  pos += 4;
+  bit_pos = pos * 8;
+
+  GET_BIT(2);  // colorspace + clamp type
+
+  // Segment header
+  if (GET_BIT(1)) {       // use_segment_
+    int s;
+    const int update_map = GET_BIT(1);
+    if (GET_BIT(1)) {     // update data
+      const int absolute_delta = GET_BIT(1);
+      int q[4]  = { 0, 0, 0, 0 };
+      for (s = 0; s < 4; ++s) {
+        if (GET_BIT(1)) {
+          q[s] = GET_BIT(7);
+          if (GET_BIT(1)) q[s] = -q[s];   // sign
+        }
+      }
+      if (absolute_delta) Q = q[0];  // just use the first segment's quantizer
+      for (s = 0; s < 4; ++s) CONDITIONAL_SKIP(7);   //  filter strength
+    }
+    if (update_map) {
+      for (s = 0; s < 3; ++s) CONDITIONAL_SKIP(8);
+    }
+  }
+  // Filter header
+  GET_BIT(1 + 6 + 3);     // simple + level + sharpness
+  if (GET_BIT(1)) {       // use_lf_delta
+    if (GET_BIT(1)) {     // update lf_delta?
+      int n;
+      for (n = 0; n < 4 + 4; ++n) CONDITIONAL_SKIP(6);
+    }
+  }
+  // num partitions
+  GET_BIT(2);
+
+  // ParseQuant
+  {
+    const int base_q = GET_BIT(7);
+    /* dqy1_dc = */ CONDITIONAL_SKIP(5);
+    /* dqy2_dc = */ CONDITIONAL_SKIP(5);
+    /* dqy2_ac = */ CONDITIONAL_SKIP(5);
+    /* dquv_dc = */ CONDITIONAL_SKIP(5);
+    /* dquv_ac = */ CONDITIONAL_SKIP(5);
+
+    if (Q < 0) Q = base_q;
+  }
+  if (bit_pos == INVALID_BIT_POS) return -1;
+
+  // base mapping
+  Q = (127 - Q) * 100 / 127;
+  // correction for power-law behavior in low range
+  if (Q < 80) {
+    Q = (int)(pow(Q / 80., 1. / 0.38) * 80);
+  }
+  return Q;
+}

extras/vwebp_sdl.c

@@ -0,0 +1,101 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Simple SDL-based WebP file viewer.
+// Does not support animation, just static images.
+//
+// Press 'q' to exit.
+//
+// Author: James Zern (jzern@google.com)
+
+#include <stdio.h>
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#if defined(WEBP_HAVE_SDL)
+
+#include "webp_to_sdl.h"
+#include "webp/decode.h"
+#include "imageio/imageio_util.h"
+#include "../examples/unicode.h"
+
+#if defined(WEBP_HAVE_JUST_SDL_H)
+#include <SDL.h>
+#else
+#include <SDL/SDL.h>
+#endif
+
+static void ProcessEvents(void) {
+  int done = 0;
+  SDL_Event event;
+  while (!done && SDL_WaitEvent(&event)) {
+    switch (event.type) {
+      case SDL_KEYUP:
+        switch (event.key.keysym.sym) {
+          case SDLK_q: done = 1; break;
+          default: break;
+        }
+        break;
+      default: break;
+    }
+  }
+}
+
+int main(int argc, char* argv[]) {
+  int c;
+  int ok = 0;
+
+  INIT_WARGV(argc, argv);
+
+  for (c = 1; c < argc; ++c) {
+    const char* file = NULL;
+    const uint8_t* webp = NULL;
+    size_t webp_size = 0;
+    if (!strcmp(argv[c], "-h")) {
+      printf("Usage: %s [-h] image.webp [more_files.webp...]\n", argv[0]);
+      FREE_WARGV_AND_RETURN(0);
+    } else {
+      file = (const char*)GET_WARGV(argv, c);
+    }
+    if (file == NULL) continue;
+    if (!ImgIoUtilReadFile(file, &webp, &webp_size)) {
+      WFPRINTF(stderr, "Error opening file: %s\n", (const W_CHAR*)file);
+      goto Error;
+    }
+    if (webp_size != (size_t)(int)webp_size) {
+      free((void*)webp);
+      fprintf(stderr, "File too large.\n");
+      goto Error;
+    }
+    ok = WebpToSDL((const char*)webp, (int)webp_size);
+    free((void*)webp);
+    if (!ok) {
+      WFPRINTF(stderr, "Error decoding file %s\n", (const W_CHAR*)file);
+      goto Error;
+    }
+    ProcessEvents();
+  }
+  ok = 1;
+
+ Error:
+  SDL_Quit();
+  FREE_WARGV_AND_RETURN(ok ? 0 : 1);
+}
+
+#else  // !WEBP_HAVE_SDL
+
+int main(int argc, const char* argv[]) {
+  fprintf(stderr, "SDL support not enabled in %s.\n", argv[0]);
+  (void)argc;
+  return 0;
+}
+
+#endif

extras/webp_quality.c

@@ -0,0 +1,54 @@
+// Simple tool to roughly evaluate the quality encoding of a webp bitstream
+//
+// Result is a *rough* estimation of the quality. You should just consider
+// the bucket it's in (q > 80? > 50? > 20?) and not take it for face value.
+/*
+ gcc -o webp_quality webp_quality.c -O3 -I../ -L. -L../imageio \
+    -limageio_util -lwebpextras -lwebp -lm -lpthread
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "extras/extras.h"
+#include "imageio/imageio_util.h"
+#include "../examples/unicode.h"
+
+int main(int argc, const char* argv[]) {
+  int c;
+  int quiet = 0;
+  int ok = 1;
+
+  INIT_WARGV(argc, argv);
+
+  for (c = 1; ok && c < argc; ++c) {
+    if (!strcmp(argv[c], "-quiet")) {
+      quiet = 1;
+    } else if (!strcmp(argv[c], "-help") || !strcmp(argv[c], "-h")) {
+      printf("webp_quality [-h][-quiet] webp_files...\n");
+      FREE_WARGV_AND_RETURN(0);
+    } else {
+      const char* const filename = (const char*)GET_WARGV(argv, c);
+      const uint8_t* data = NULL;
+      size_t data_size = 0;
+      int q;
+      ok = ImgIoUtilReadFile(filename, &data, &data_size);
+      if (!ok) break;
+      q = VP8EstimateQuality(data, data_size);
+      if (!quiet) WPRINTF("[%s] ", (const W_CHAR*)filename);
+      if (q < 0) {
+        fprintf(stderr, "Not a WebP file, or not a lossy WebP file.\n");
+        ok = 0;
+      } else {
+        if (!quiet) {
+          printf("Estimated quality factor: %d\n", q);
+        } else {
+          printf("%d\n", q);   // just print the number
+        }
+      }
+      free((void*)data);
+    }
+  }
+  FREE_WARGV_AND_RETURN(ok ? 0 : 1);
+}

extras/webp_to_sdl.c

@@ -0,0 +1,110 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  Simple WebP-to-SDL wrapper. Useful for emscripten.
+//
+// Author: James Zern (jzern@google.com)
+
+#ifdef HAVE_CONFIG_H
+#include "src/webp/config.h"
+#endif
+
+#if defined(WEBP_HAVE_SDL)
+
+#include "webp_to_sdl.h"
+
+#include <stdio.h>
+#include "src/webp/decode.h"
+
+#if defined(WEBP_HAVE_JUST_SDL_H)
+#include <SDL.h>
+#else
+#include <SDL/SDL.h>
+#endif
+
+static int init_ok = 0;
+int WebpToSDL(const char* data, unsigned int data_size) {
+  int ok = 0;
+  VP8StatusCode status;
+  WebPDecoderConfig config;
+  WebPBitstreamFeatures* const input = &config.input;
+  WebPDecBuffer* const output = &config.output;
+  SDL_Surface* screen = NULL;
+  SDL_Surface* surface = NULL;
+
+  if (!WebPInitDecoderConfig(&config)) {
+    fprintf(stderr, "Library version mismatch!\n");
+    return 0;
+  }
+
+  if (!init_ok) {
+    SDL_Init(SDL_INIT_VIDEO);
+    init_ok = 1;
+  }
+
+  status = WebPGetFeatures((uint8_t*)data, (size_t)data_size, &config.input);
+  if (status != VP8_STATUS_OK) goto Error;
+
+  screen = SDL_SetVideoMode(input->width, input->height, 32, SDL_SWSURFACE);
+  if (screen == NULL) {
+    fprintf(stderr, "Unable to set video mode (32bpp %dx%d)!\n",
+            input->width, input->height);
+    goto Error;
+  }
+
+  surface = SDL_CreateRGBSurface(SDL_SWSURFACE,
+                                 input->width, input->height, 32,
+                                 0x000000ffu,   // R mask
+                                 0x0000ff00u,   // G mask
+                                 0x00ff0000u,   // B mask
+                                 0xff000000u);  // A mask
+
+  if (surface == NULL) {
+    fprintf(stderr, "Unable to create %dx%d RGBA surface!\n",
+            input->width, input->height);
+    goto Error;
+  }
+  if (SDL_MUSTLOCK(surface)) SDL_LockSurface(surface);
+
+#if SDL_BYTEORDER == SDL_BIG_ENDIAN
+  output->colorspace = MODE_BGRA;
+#else
+  output->colorspace = MODE_RGBA;
+#endif
+  output->width  = surface->w;
+  output->height = surface->h;
+  output->u.RGBA.rgba   = surface->pixels;
+  output->u.RGBA.stride = surface->pitch;
+  output->u.RGBA.size   = surface->pitch * surface->h;
+  output->is_external_memory = 1;
+
+  status = WebPDecode((const uint8_t*)data, (size_t)data_size, &config);
+  if (status != VP8_STATUS_OK) {
+    fprintf(stderr, "Error decoding image (%d)\n", status);
+    goto Error;
+  }
+
+  if (SDL_MUSTLOCK(surface)) SDL_UnlockSurface(surface);
+  if (SDL_BlitSurface(surface, NULL, screen, NULL) ||
+      SDL_Flip(screen)) {
+    goto Error;
+  }
+
+  ok = 1;
+
+ Error:
+  SDL_FreeSurface(surface);
+  SDL_FreeSurface(screen);
+  WebPFreeDecBuffer(output);
+  return ok;
+}
+
+//------------------------------------------------------------------------------
+
+#endif  // WEBP_HAVE_SDL

extras/webp_to_sdl.h

@@ -0,0 +1,22 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  Simple WebP-to-SDL wrapper. Useful for emscripten.
+//
+// Author: James Zern (jzern@google.com)
+
+#ifndef WEBP_EXTRAS_WEBP_TO_SDL_H_
+#define WEBP_EXTRAS_WEBP_TO_SDL_H_
+
+// Exports the method WebpToSDL(const char* data, int data_size) which decodes
+// a WebP bitstream into an RGBA SDL surface.
+// Return false on failure.
+extern int WebpToSDL(const char* data, unsigned int data_size);
+
+#endif  // WEBP_EXTRAS_WEBP_TO_SDL_H_

gradle.properties

@@ -0,0 +1,14 @@
+# Project-wide Gradle settings.
+
+# IDE (e.g. Android Studio) users:
+# Gradle settings configured through the IDE *will override*
+# any settings specified in this file.
+
+# For more details on how to configure your build environment visit
+# http://www.gradle.org/docs/current/userguide/build_environment.html
+
+# Versions for gradle
+BUILD_TOOLS_VERSION=23.0.3
+COMPILE_SDK_VERSION=23
+ANDROID_GRADLE_PLUGIN_VERSION=1.5.0
+GRADLE_DOWNLOAD_TASK_VERSION=2.1.0

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.1.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

@@ -0,0 +1,183 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"

gradlew.bat

@@ -0,0 +1,100 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

imageio/Android.mk

@@ -0,0 +1,54 @@
+LOCAL_PATH := $(call my-dir)
+
+################################################################################
+# libimageio_util
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    imageio_util.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
+
+LOCAL_MODULE := imageio_util
+
+include $(BUILD_STATIC_LIBRARY)
+
+################################################################################
+# libimagedec
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    image_dec.c \
+    jpegdec.c \
+    metadata.c \
+    pngdec.c \
+    pnmdec.c \
+    tiffdec.c \
+    webpdec.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
+LOCAL_STATIC_LIBRARIES := imageio_util
+
+LOCAL_MODULE := imagedec
+
+include $(BUILD_STATIC_LIBRARY)
+
+################################################################################
+# libimageenc
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+    image_enc.c \
+
+LOCAL_CFLAGS := $(WEBP_CFLAGS)
+LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
+LOCAL_STATIC_LIBRARIES := imageio_util
+
+LOCAL_MODULE := imageenc
+
+include $(BUILD_STATIC_LIBRARY)

imageio/Makefile.am

@@ -0,0 +1,32 @@
+AM_CPPFLAGS += -I$(top_builddir)/src -I$(top_srcdir)/src
+noinst_LTLIBRARIES =
+noinst_LTLIBRARIES += libimageio_util.la
+if BUILD_DEMUX
+  noinst_LTLIBRARIES += libimagedec.la
+endif
+noinst_LTLIBRARIES += libimageenc.la
+
+noinst_HEADERS =
+noinst_HEADERS += ../src/webp/decode.h
+noinst_HEADERS += ../src/webp/types.h
+
+libimageio_util_la_SOURCES =
+libimageio_util_la_SOURCES += imageio_util.c imageio_util.h
+
+libimagedec_la_SOURCES  =
+libimagedec_la_SOURCES += image_dec.c image_dec.h
+libimagedec_la_SOURCES += jpegdec.c jpegdec.h
+libimagedec_la_SOURCES += metadata.c metadata.h
+libimagedec_la_SOURCES += pngdec.c pngdec.h
+libimagedec_la_SOURCES += pnmdec.c pnmdec.h
+libimagedec_la_SOURCES += tiffdec.c tiffdec.h
+libimagedec_la_SOURCES += webpdec.c webpdec.h
+libimagedec_la_SOURCES += wicdec.c wicdec.h
+libimagedec_la_CPPFLAGS = $(JPEG_INCLUDES) $(PNG_INCLUDES) $(TIFF_INCLUDES)
+libimagedec_la_CPPFLAGS += $(AM_CPPFLAGS)
+libimagedec_la_LIBADD = ../src/demux/libwebpdemux.la
+
+libimageenc_la_SOURCES  =
+libimageenc_la_SOURCES += image_enc.c image_enc.h
+libimageenc_la_CPPFLAGS = $(JPEG_INCLUDES) $(PNG_INCLUDES) $(TIFF_INCLUDES)
+libimageenc_la_CPPFLAGS += $(AM_CPPFLAGS)

imageio/image_dec.c

@@ -0,0 +1,84 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Generic image-type guessing.
+
+#include "./image_dec.h"
+
+const char* WebPGetEnabledInputFileFormats(void) {
+  return "WebP"
+#ifdef WEBP_HAVE_JPEG
+         ", JPEG"
+#endif
+#ifdef WEBP_HAVE_PNG
+         ", PNG"
+#endif
+         ", PNM (PGM, PPM, PAM)"
+#ifdef WEBP_HAVE_TIFF
+         ", TIFF"
+#endif
+#ifdef HAVE_WINCODEC_H
+         ", Windows Imaging Component (WIC)"
+#endif
+         "";
+}
+
+static WEBP_INLINE uint32_t GetBE32(const uint8_t buf[]) {
+  return ((uint32_t)buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | buf[3];
+}
+
+WebPInputFileFormat WebPGuessImageType(const uint8_t* const data,
+                                       size_t data_size) {
+  WebPInputFileFormat format = WEBP_UNSUPPORTED_FORMAT;
+  if (data != NULL && data_size >= 12) {
+    const uint32_t magic1 = GetBE32(data + 0);
+    const uint32_t magic2 = GetBE32(data + 8);
+    if (magic1 == 0x89504E47U) {
+      format = WEBP_PNG_FORMAT;
+    } else if (magic1 >= 0xFFD8FF00U && magic1 <= 0xFFD8FFFFU) {
+      format = WEBP_JPEG_FORMAT;
+    } else if (magic1 == 0x49492A00 || magic1 == 0x4D4D002A) {
+      format = WEBP_TIFF_FORMAT;
+    } else if (magic1 == 0x52494646 && magic2 == 0x57454250) {
+      format = WEBP_WEBP_FORMAT;
+    } else if (((magic1 >> 24) & 0xff) == 'P') {
+      const int type = (magic1 >> 16) & 0xff;
+      // we only support 'P5 -> P7' for now.
+      if (type >= '5' && type <= '7') format = WEBP_PNM_FORMAT;
+    }
+  }
+  return format;
+}
+
+static int FailReader(const uint8_t* const data, size_t data_size,
+                      struct WebPPicture* const pic,
+                      int keep_alpha, struct Metadata* const metadata) {
+  (void)data;
+  (void)data_size;
+  (void)pic;
+  (void)keep_alpha;
+  (void)metadata;
+  return 0;
+}
+
+WebPImageReader WebPGetImageReader(WebPInputFileFormat format) {
+  switch (format) {
+    case WEBP_PNG_FORMAT: return ReadPNG;
+    case WEBP_JPEG_FORMAT: return ReadJPEG;
+    case WEBP_TIFF_FORMAT: return ReadTIFF;
+    case WEBP_WEBP_FORMAT: return ReadWebP;
+    case WEBP_PNM_FORMAT: return ReadPNM;
+    default: return FailReader;
+  }
+}
+
+WebPImageReader WebPGuessImageReader(const uint8_t* const data,
+                                     size_t data_size) {
+  return WebPGetImageReader(WebPGuessImageType(data, data_size));
+}

imageio/image_dec.h

@@ -0,0 +1,70 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  All-in-one library to decode PNG/JPEG/WebP/TIFF/WIC input images.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifndef WEBP_IMAGEIO_IMAGE_DEC_H_
+#define WEBP_IMAGEIO_IMAGE_DEC_H_
+
+#include "webp/types.h"
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#include "./metadata.h"
+#include "./jpegdec.h"
+#include "./pngdec.h"
+#include "./pnmdec.h"
+#include "./tiffdec.h"
+#include "./webpdec.h"
+#include "./wicdec.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum {
+  WEBP_PNG_FORMAT = 0,
+  WEBP_JPEG_FORMAT,
+  WEBP_TIFF_FORMAT,
+  WEBP_WEBP_FORMAT,
+  WEBP_PNM_FORMAT,
+  WEBP_UNSUPPORTED_FORMAT
+} WebPInputFileFormat;
+
+// Returns a comma separated list of enabled input formats.
+const char* WebPGetEnabledInputFileFormats(void);
+
+// Try to infer the image format. 'data_size' should be larger than 12.
+// Returns WEBP_UNSUPPORTED_FORMAT if format can't be guess safely.
+WebPInputFileFormat WebPGuessImageType(const uint8_t* const data,
+                                       size_t data_size);
+
+// Signature for common image-reading functions (ReadPNG, ReadJPEG, ...)
+typedef int (*WebPImageReader)(const uint8_t* const data, size_t data_size,
+                               struct WebPPicture* const pic,
+                               int keep_alpha, struct Metadata* const metadata);
+
+// Return the reader associated to a given file format.
+WebPImageReader WebPGetImageReader(WebPInputFileFormat format);
+
+// This function is similar to WebPGuessImageType(), but returns a
+// suitable reader function. The returned reader is never NULL, but
+// unknown formats will return an always-failing valid reader.
+WebPImageReader WebPGuessImageReader(const uint8_t* const data,
+                                     size_t data_size);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_IMAGEIO_IMAGE_DEC_H_

imageio/image_enc.c

@@ -0,0 +1,615 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Save image
+
+#include "./image_enc.h"
+
+#include <assert.h>
+#include <string.h>
+
+#ifdef WEBP_HAVE_PNG
+#include <png.h>
+#include <setjmp.h>   // note: this must be included *after* png.h
+#endif
+
+#ifdef HAVE_WINCODEC_H
+#ifdef __MINGW32__
+#define INITGUID  // Without this GUIDs are declared extern and fail to link
+#endif
+#define CINTERFACE
+#define COBJMACROS
+#define _WIN32_IE 0x500  // Workaround bug in shlwapi.h when compiling C++
+                         // code with COBJMACROS.
+#include <ole2.h>  // CreateStreamOnHGlobal()
+#include <shlwapi.h>
+#include <tchar.h>
+#include <windows.h>
+#include <wincodec.h>
+#endif
+
+#include "./imageio_util.h"
+#include "../examples/unicode.h"
+
+//------------------------------------------------------------------------------
+// PNG
+
+#ifdef HAVE_WINCODEC_H
+
+#define IFS(fn)                                                     \
+  do {                                                              \
+    if (SUCCEEDED(hr)) {                                            \
+      hr = (fn);                                                    \
+      if (FAILED(hr)) fprintf(stderr, #fn " failed %08lx\n", hr);   \
+    }                                                               \
+  } while (0)
+
+#ifdef __cplusplus
+#define MAKE_REFGUID(x) (x)
+#else
+#define MAKE_REFGUID(x) &(x)
+#endif
+
+static HRESULT CreateOutputStream(const char* out_file_name,
+                                  int write_to_mem, IStream** stream) {
+  HRESULT hr = S_OK;
+  if (write_to_mem) {
+    // Output to a memory buffer. This is freed when 'stream' is released.
+    IFS(CreateStreamOnHGlobal(NULL, TRUE, stream));
+  } else {
+    IFS(SHCreateStreamOnFile((const LPTSTR)out_file_name,
+                             STGM_WRITE | STGM_CREATE, stream));
+  }
+  if (FAILED(hr)) {
+    _ftprintf(stderr, _T("Error opening output file %s (%08lx)\n"),
+              (const LPTSTR)out_file_name, hr);
+  }
+  return hr;
+}
+
+static HRESULT WriteUsingWIC(const char* out_file_name, int use_stdout,
+                             REFGUID container_guid,
+                             uint8_t* rgb, int stride,
+                             uint32_t width, uint32_t height, int has_alpha) {
+  HRESULT hr = S_OK;
+  IWICImagingFactory* factory = NULL;
+  IWICBitmapFrameEncode* frame = NULL;
+  IWICBitmapEncoder* encoder = NULL;
+  IStream* stream = NULL;
+  WICPixelFormatGUID pixel_format = has_alpha ? GUID_WICPixelFormat32bppBGRA
+                                              : GUID_WICPixelFormat24bppBGR;
+
+  if (out_file_name == NULL || rgb == NULL) return E_INVALIDARG;
+
+  IFS(CoInitialize(NULL));
+  IFS(CoCreateInstance(MAKE_REFGUID(CLSID_WICImagingFactory), NULL,
+                       CLSCTX_INPROC_SERVER,
+                       MAKE_REFGUID(IID_IWICImagingFactory),
+                       (LPVOID*)&factory));
+  if (hr == REGDB_E_CLASSNOTREG) {
+    fprintf(stderr,
+            "Couldn't access Windows Imaging Component (are you running "
+            "Windows XP SP3 or newer?). PNG support not available. "
+            "Use -ppm or -pgm for available PPM and PGM formats.\n");
+  }
+  IFS(CreateOutputStream(out_file_name, use_stdout, &stream));
+  IFS(IWICImagingFactory_CreateEncoder(factory, container_guid, NULL,
+                                       &encoder));
+  IFS(IWICBitmapEncoder_Initialize(encoder, stream,
+                                   WICBitmapEncoderNoCache));
+  IFS(IWICBitmapEncoder_CreateNewFrame(encoder, &frame, NULL));
+  IFS(IWICBitmapFrameEncode_Initialize(frame, NULL));
+  IFS(IWICBitmapFrameEncode_SetSize(frame, width, height));
+  IFS(IWICBitmapFrameEncode_SetPixelFormat(frame, &pixel_format));
+  IFS(IWICBitmapFrameEncode_WritePixels(frame, height, stride,
+                                        height * stride, rgb));
+  IFS(IWICBitmapFrameEncode_Commit(frame));
+  IFS(IWICBitmapEncoder_Commit(encoder));
+
+  if (SUCCEEDED(hr) && use_stdout) {
+    HGLOBAL image;
+    IFS(GetHGlobalFromStream(stream, &image));
+    if (SUCCEEDED(hr)) {
+      HANDLE std_output = GetStdHandle(STD_OUTPUT_HANDLE);
+      DWORD mode;
+      const BOOL update_mode = GetConsoleMode(std_output, &mode);
+      const void* const image_mem = GlobalLock(image);
+      DWORD bytes_written = 0;
+
+      // Clear output processing if necessary, then output the image.
+      if (update_mode) SetConsoleMode(std_output, 0);
+      if (!WriteFile(std_output, image_mem, (DWORD)GlobalSize(image),
+                     &bytes_written, NULL) ||
+          bytes_written != GlobalSize(image)) {
+        hr = E_FAIL;
+      }
+      if (update_mode) SetConsoleMode(std_output, mode);
+      GlobalUnlock(image);
+    }
+  }
+
+  if (frame != NULL) IUnknown_Release(frame);
+  if (encoder != NULL) IUnknown_Release(encoder);
+  if (factory != NULL) IUnknown_Release(factory);
+  if (stream != NULL) IUnknown_Release(stream);
+  return hr;
+}
+
+int WebPWritePNG(const char* out_file_name, int use_stdout,
+                 const WebPDecBuffer* const buffer) {
+  const uint32_t width = buffer->width;
+  const uint32_t height = buffer->height;
+  uint8_t* const rgb = buffer->u.RGBA.rgba;
+  const int stride = buffer->u.RGBA.stride;
+  const int has_alpha = WebPIsAlphaMode(buffer->colorspace);
+
+  return SUCCEEDED(WriteUsingWIC(out_file_name, use_stdout,
+                                 MAKE_REFGUID(GUID_ContainerFormatPng),
+                                 rgb, stride, width, height, has_alpha));
+}
+
+#elif defined(WEBP_HAVE_PNG)    // !HAVE_WINCODEC_H
+static void PNGAPI PNGErrorFunction(png_structp png, png_const_charp unused) {
+  (void)unused;  // remove variable-unused warning
+  longjmp(png_jmpbuf(png), 1);
+}
+
+int WebPWritePNG(FILE* out_file, const WebPDecBuffer* const buffer) {
+  volatile png_structp png;
+  volatile png_infop info;
+
+  if (out_file == NULL || buffer == NULL) return 0;
+
+  png = png_create_write_struct(PNG_LIBPNG_VER_STRING,
+                                NULL, PNGErrorFunction, NULL);
+  if (png == NULL) {
+    return 0;
+  }
+  info = png_create_info_struct(png);
+  if (info == NULL) {
+    png_destroy_write_struct((png_structpp)&png, NULL);
+    return 0;
+  }
+  if (setjmp(png_jmpbuf(png))) {
+    png_destroy_write_struct((png_structpp)&png, (png_infopp)&info);
+    return 0;
+  }
+  png_init_io(png, out_file);
+  {
+    const uint32_t width = buffer->width;
+    const uint32_t height = buffer->height;
+    png_bytep row = buffer->u.RGBA.rgba;
+    const int stride = buffer->u.RGBA.stride;
+    const int has_alpha = WebPIsAlphaMode(buffer->colorspace);
+    uint32_t y;
+
+    png_set_IHDR(png, info, width, height, 8,
+                 has_alpha ? PNG_COLOR_TYPE_RGBA : PNG_COLOR_TYPE_RGB,
+                 PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
+                 PNG_FILTER_TYPE_DEFAULT);
+    png_write_info(png, info);
+    for (y = 0; y < height; ++y) {
+      png_write_rows(png, &row, 1);
+      row += stride;
+    }
+  }
+  png_write_end(png, info);
+  png_destroy_write_struct((png_structpp)&png, (png_infopp)&info);
+  return 1;
+}
+#else    // !HAVE_WINCODEC_H && !WEBP_HAVE_PNG
+int WebPWritePNG(FILE* fout, const WebPDecBuffer* const buffer) {
+  if (fout == NULL || buffer == NULL) return 0;
+
+  fprintf(stderr, "PNG support not compiled. Please install the libpng "
+          "development package before building.\n");
+  fprintf(stderr, "You can run with -ppm flag to decode in PPM format.\n");
+  return 0;
+}
+#endif
+
+//------------------------------------------------------------------------------
+// PPM / PAM
+
+static int WritePPMPAM(FILE* fout, const WebPDecBuffer* const buffer,
+                       int alpha) {
+  if (fout == NULL || buffer == NULL) {
+    return 0;
+  } else {
+    const uint32_t width = buffer->width;
+    const uint32_t height = buffer->height;
+    const uint8_t* row = buffer->u.RGBA.rgba;
+    const int stride = buffer->u.RGBA.stride;
+    const size_t bytes_per_px = alpha ? 4 : 3;
+    uint32_t y;
+
+    if (row == NULL) return 0;
+
+    if (alpha) {
+      fprintf(fout, "P7\nWIDTH %u\nHEIGHT %u\nDEPTH 4\nMAXVAL 255\n"
+                    "TUPLTYPE RGB_ALPHA\nENDHDR\n", width, height);
+    } else {
+      fprintf(fout, "P6\n%u %u\n255\n", width, height);
+    }
+    for (y = 0; y < height; ++y) {
+      if (fwrite(row, width, bytes_per_px, fout) != bytes_per_px) {
+        return 0;
+      }
+      row += stride;
+    }
+  }
+  return 1;
+}
+
+int WebPWritePPM(FILE* fout, const WebPDecBuffer* const buffer) {
+  return WritePPMPAM(fout, buffer, 0);
+}
+
+int WebPWritePAM(FILE* fout, const WebPDecBuffer* const buffer) {
+  return WritePPMPAM(fout, buffer, 1);
+}
+
+//------------------------------------------------------------------------------
+// Raw PGM
+
+// Save 16b mode (RGBA4444, RGB565, ...) for debugging purpose.
+int WebPWrite16bAsPGM(FILE* fout, const WebPDecBuffer* const buffer) {
+  const uint32_t width = buffer->width;
+  const uint32_t height = buffer->height;
+  const uint8_t* rgba = buffer->u.RGBA.rgba;
+  const int stride = buffer->u.RGBA.stride;
+  const uint32_t bytes_per_px = 2;
+  uint32_t y;
+
+  if (fout == NULL || buffer == NULL || rgba == NULL) return 0;
+
+  fprintf(fout, "P5\n%u %u\n255\n", width * bytes_per_px, height);
+  for (y = 0; y < height; ++y) {
+    if (fwrite(rgba, width, bytes_per_px, fout) != bytes_per_px) {
+      return 0;
+    }
+    rgba += stride;
+  }
+  return 1;
+}
+
+//------------------------------------------------------------------------------
+// BMP (see https://en.wikipedia.org/wiki/BMP_file_format#Pixel_storage)
+
+static void PutLE16(uint8_t* const dst, uint32_t value) {
+  dst[0] = (value >> 0) & 0xff;
+  dst[1] = (value >> 8) & 0xff;
+}
+
+static void PutLE32(uint8_t* const dst, uint32_t value) {
+  PutLE16(dst + 0, (value >>  0) & 0xffff);
+  PutLE16(dst + 2, (value >> 16) & 0xffff);
+}
+
+#define BMP_HEADER_SIZE 54
+#define BMP_HEADER_ALPHA_EXTRA_SIZE 16  // for alpha info
+int WebPWriteBMP(FILE* fout, const WebPDecBuffer* const buffer) {
+  const int has_alpha = WebPIsAlphaMode(buffer->colorspace);
+  const int header_size =
+      BMP_HEADER_SIZE + (has_alpha ? BMP_HEADER_ALPHA_EXTRA_SIZE : 0);
+  const uint32_t width = buffer->width;
+  const uint32_t height = buffer->height;
+  const uint8_t* rgba = buffer->u.RGBA.rgba;
+  const int stride = buffer->u.RGBA.stride;
+  const uint32_t bytes_per_px = has_alpha ? 4 : 3;
+  uint32_t y;
+  const uint32_t line_size = bytes_per_px * width;
+  const uint32_t bmp_stride = (line_size + 3) & ~3;   // pad to 4
+  const uint32_t image_size = bmp_stride * height;
+  const uint32_t total_size =  image_size + header_size;
+  uint8_t bmp_header[BMP_HEADER_SIZE + BMP_HEADER_ALPHA_EXTRA_SIZE] = { 0 };
+
+  if (fout == NULL || buffer == NULL || rgba == NULL) return 0;
+
+  // bitmap file header
+  PutLE16(bmp_header + 0, 0x4d42);                // signature 'BM'
+  PutLE32(bmp_header + 2, total_size);            // size including header
+  PutLE32(bmp_header + 6, 0);                     // reserved
+  PutLE32(bmp_header + 10, header_size);          // offset to pixel array
+  // bitmap info header
+  PutLE32(bmp_header + 14, header_size - 14);     // DIB header size
+  PutLE32(bmp_header + 18, width);                // dimensions
+  PutLE32(bmp_header + 22, height);               // no vertical flip
+  PutLE16(bmp_header + 26, 1);                    // number of planes
+  PutLE16(bmp_header + 28, bytes_per_px * 8);     // bits per pixel
+  PutLE32(bmp_header + 30, has_alpha ? 3 : 0);    // BI_BITFIELDS or BI_RGB
+  PutLE32(bmp_header + 34, image_size);
+  PutLE32(bmp_header + 38, 2400);                 // x pixels/meter
+  PutLE32(bmp_header + 42, 2400);                 // y pixels/meter
+  PutLE32(bmp_header + 46, 0);                    // number of palette colors
+  PutLE32(bmp_header + 50, 0);                    // important color count
+  if (has_alpha) {  // BITMAPV3INFOHEADER complement
+    PutLE32(bmp_header + 54, 0x00ff0000);         // red mask
+    PutLE32(bmp_header + 58, 0x0000ff00);         // green mask
+    PutLE32(bmp_header + 62, 0x000000ff);         // blue mask
+    PutLE32(bmp_header + 66, 0xff000000);         // alpha mask
+  }
+
+  // TODO(skal): color profile
+
+  // write header
+  if (fwrite(bmp_header, header_size, 1, fout) != 1) {
+    return 0;
+  }
+
+  // write pixel array, bottom to top
+  for (y = 0; y < height; ++y) {
+    const uint8_t* const src = &rgba[(uint64_t)(height - 1 - y) * stride];
+    if (fwrite(src, line_size, 1, fout) != 1) {
+      return 0;
+    }
+    // write padding zeroes
+    if (bmp_stride != line_size) {
+      const uint8_t zeroes[3] = { 0 };
+      if (fwrite(zeroes, bmp_stride - line_size, 1, fout) != 1) {
+        return 0;
+      }
+    }
+  }
+  return 1;
+}
+#undef BMP_HEADER_SIZE
+#undef BMP_HEADER_ALPHA_EXTRA_SIZE
+
+//------------------------------------------------------------------------------
+// TIFF
+
+#define NUM_IFD_ENTRIES 15
+#define EXTRA_DATA_SIZE 16
+// 10b for signature/header + n * 12b entries + 4b for IFD terminator:
+#define EXTRA_DATA_OFFSET (10 + 12 * NUM_IFD_ENTRIES + 4)
+#define TIFF_HEADER_SIZE (EXTRA_DATA_OFFSET + EXTRA_DATA_SIZE)
+
+int WebPWriteTIFF(FILE* fout, const WebPDecBuffer* const buffer) {
+  const int has_alpha = WebPIsAlphaMode(buffer->colorspace);
+  const uint32_t width = buffer->width;
+  const uint32_t height = buffer->height;
+  const uint8_t* rgba = buffer->u.RGBA.rgba;
+  const int stride = buffer->u.RGBA.stride;
+  const uint8_t bytes_per_px = has_alpha ? 4 : 3;
+  const uint8_t assoc_alpha =
+      WebPIsPremultipliedMode(buffer->colorspace) ? 1 : 2;
+  // For non-alpha case, we omit tag 0x152 (ExtraSamples).
+  const uint8_t num_ifd_entries = has_alpha ? NUM_IFD_ENTRIES
+                                            : NUM_IFD_ENTRIES - 1;
+  uint8_t tiff_header[TIFF_HEADER_SIZE] = {
+    0x49, 0x49, 0x2a, 0x00,   // little endian signature
+    8, 0, 0, 0,               // offset to the unique IFD that follows
+    // IFD (offset = 8). Entries must be written in increasing tag order.
+    num_ifd_entries, 0,       // Number of entries in the IFD (12 bytes each).
+    0x00, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0,    //  10: Width  (TBD)
+    0x01, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0,    //  22: Height (TBD)
+    0x02, 0x01, 3, 0, bytes_per_px, 0, 0, 0,     //  34: BitsPerSample: 8888
+        EXTRA_DATA_OFFSET + 0, 0, 0, 0,
+    0x03, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0,    //  46: Compression: none
+    0x06, 0x01, 3, 0, 1, 0, 0, 0, 2, 0, 0, 0,    //  58: Photometric: RGB
+    0x11, 0x01, 4, 0, 1, 0, 0, 0,                //  70: Strips offset:
+        TIFF_HEADER_SIZE, 0, 0, 0,               //      data follows header
+    0x12, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0,    //  82: Orientation: topleft
+    0x15, 0x01, 3, 0, 1, 0, 0, 0,                //  94: SamplesPerPixels
+        bytes_per_px, 0, 0, 0,
+    0x16, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0,    // 106: Rows per strip (TBD)
+    0x17, 0x01, 4, 0, 1, 0, 0, 0, 0, 0, 0, 0,    // 118: StripByteCount (TBD)
+    0x1a, 0x01, 5, 0, 1, 0, 0, 0,                // 130: X-resolution
+        EXTRA_DATA_OFFSET + 8, 0, 0, 0,
+    0x1b, 0x01, 5, 0, 1, 0, 0, 0,                // 142: Y-resolution
+        EXTRA_DATA_OFFSET + 8, 0, 0, 0,
+    0x1c, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0,    // 154: PlanarConfiguration
+    0x28, 0x01, 3, 0, 1, 0, 0, 0, 2, 0, 0, 0,    // 166: ResolutionUnit (inch)
+    0x52, 0x01, 3, 0, 1, 0, 0, 0,
+        assoc_alpha, 0, 0, 0,                    // 178: ExtraSamples: rgbA/RGBA
+    0, 0, 0, 0,                                  // 190: IFD terminator
+    // EXTRA_DATA_OFFSET:
+    8, 0, 8, 0, 8, 0, 8, 0,      // BitsPerSample
+    72, 0, 0, 0, 1, 0, 0, 0      // 72 pixels/inch, for X/Y-resolution
+  };
+  uint32_t y;
+
+  if (fout == NULL || buffer == NULL || rgba == NULL) return 0;
+
+  // Fill placeholders in IFD:
+  PutLE32(tiff_header + 10 + 8, width);
+  PutLE32(tiff_header + 22 + 8, height);
+  PutLE32(tiff_header + 106 + 8, height);
+  PutLE32(tiff_header + 118 + 8, width * bytes_per_px * height);
+  if (!has_alpha) PutLE32(tiff_header + 178, 0);  // IFD terminator
+
+  // write header
+  if (fwrite(tiff_header, sizeof(tiff_header), 1, fout) != 1) {
+    return 0;
+  }
+  // write pixel values
+  for (y = 0; y < height; ++y) {
+    if (fwrite(rgba, bytes_per_px, width, fout) != width) {
+      return 0;
+    }
+    rgba += stride;
+  }
+
+  return 1;
+}
+
+#undef TIFF_HEADER_SIZE
+#undef EXTRA_DATA_OFFSET
+#undef EXTRA_DATA_SIZE
+#undef NUM_IFD_ENTRIES
+
+//------------------------------------------------------------------------------
+// Raw Alpha
+
+int WebPWriteAlphaPlane(FILE* fout, const WebPDecBuffer* const buffer) {
+  if (fout == NULL || buffer == NULL) {
+    return 0;
+  } else {
+    const uint32_t width = buffer->width;
+    const uint32_t height = buffer->height;
+    const uint8_t* a = buffer->u.YUVA.a;
+    const int a_stride = buffer->u.YUVA.a_stride;
+    uint32_t y;
+
+    if (a == NULL) return 0;
+
+    fprintf(fout, "P5\n%u %u\n255\n", width, height);
+    for (y = 0; y < height; ++y) {
+      if (fwrite(a, width, 1, fout) != 1) return 0;
+      a += a_stride;
+    }
+    return 1;
+  }
+}
+
+//------------------------------------------------------------------------------
+// PGM with IMC4 layout
+
+int WebPWritePGM(FILE* fout, const WebPDecBuffer* const buffer) {
+  if (fout == NULL || buffer == NULL) {
+    return 0;
+  } else {
+    const int width = buffer->width;
+    const int height = buffer->height;
+    const WebPYUVABuffer* const yuv = &buffer->u.YUVA;
+    const uint8_t* src_y = yuv->y;
+    const uint8_t* src_u = yuv->u;
+    const uint8_t* src_v = yuv->v;
+    const uint8_t* src_a = yuv->a;
+    const int uv_width = (width + 1) / 2;
+    const int uv_height = (height + 1) / 2;
+    const int a_height = (src_a != NULL) ? height : 0;
+    int ok = 1;
+    int y;
+
+    if (src_y == NULL || src_u == NULL || src_v == NULL) return 0;
+
+    fprintf(fout, "P5\n%d %d\n255\n",
+            (width + 1) & ~1, height + uv_height + a_height);
+    for (y = 0; ok && y < height; ++y) {
+      ok &= (fwrite(src_y, width, 1, fout) == 1);
+      if (width & 1) fputc(0, fout);    // padding byte
+      src_y += yuv->y_stride;
+    }
+    for (y = 0; ok && y < uv_height; ++y) {
+      ok &= (fwrite(src_u, uv_width, 1, fout) == 1);
+      ok &= (fwrite(src_v, uv_width, 1, fout) == 1);
+      src_u += yuv->u_stride;
+      src_v += yuv->v_stride;
+    }
+    for (y = 0; ok && y < a_height; ++y) {
+      ok &= (fwrite(src_a, width, 1, fout) == 1);
+      if (width & 1) fputc(0, fout);    // padding byte
+      src_a += yuv->a_stride;
+    }
+    return ok;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Raw YUV(A) planes
+
+int WebPWriteYUV(FILE* fout, const WebPDecBuffer* const buffer) {
+  if (fout == NULL || buffer == NULL) {
+    return 0;
+  } else {
+    const int width = buffer->width;
+    const int height = buffer->height;
+    const WebPYUVABuffer* const yuv = &buffer->u.YUVA;
+    const uint8_t* src_y = yuv->y;
+    const uint8_t* src_u = yuv->u;
+    const uint8_t* src_v = yuv->v;
+    const uint8_t* src_a = yuv->a;
+    const int uv_width = (width + 1) / 2;
+    const int uv_height = (height + 1) / 2;
+    const int a_height = (src_a != NULL) ? height : 0;
+    int ok = 1;
+    int y;
+
+    if (src_y == NULL || src_u == NULL || src_v == NULL) return 0;
+
+    for (y = 0; ok && y < height; ++y) {
+      ok &= (fwrite(src_y, width, 1, fout) == 1);
+      src_y += yuv->y_stride;
+    }
+    for (y = 0; ok && y < uv_height; ++y) {
+      ok &= (fwrite(src_u, uv_width, 1, fout) == 1);
+      src_u += yuv->u_stride;
+    }
+    for (y = 0; ok && y < uv_height; ++y) {
+      ok &= (fwrite(src_v, uv_width, 1, fout) == 1);
+      src_v += yuv->v_stride;
+    }
+    for (y = 0; ok && y < a_height; ++y) {
+      ok &= (fwrite(src_a, width, 1, fout) == 1);
+      src_a += yuv->a_stride;
+    }
+    return ok;
+  }
+}
+
+//------------------------------------------------------------------------------
+// Generic top-level call
+
+int WebPSaveImage(const WebPDecBuffer* const buffer,
+                  WebPOutputFileFormat format,
+                  const char* const out_file_name) {
+  FILE* fout = NULL;
+  int needs_open_file = 1;
+  const int use_stdout =
+      (out_file_name != NULL) && !WSTRCMP(out_file_name, "-");
+  int ok = 1;
+
+  if (buffer == NULL || out_file_name == NULL) return 0;
+
+#ifdef HAVE_WINCODEC_H
+  needs_open_file = (format != PNG);
+#endif
+
+  if (needs_open_file) {
+    fout = use_stdout ? ImgIoUtilSetBinaryMode(stdout)
+                      : WFOPEN(out_file_name, "wb");
+    if (fout == NULL) {
+      WFPRINTF(stderr, "Error opening output file %s\n",
+               (const W_CHAR*)out_file_name);
+      return 0;
+    }
+  }
+
+  if (format == PNG ||
+      format == RGBA || format == BGRA || format == ARGB ||
+      format == rgbA || format == bgrA || format == Argb) {
+#ifdef HAVE_WINCODEC_H
+    ok &= WebPWritePNG(out_file_name, use_stdout, buffer);
+#else
+    ok &= WebPWritePNG(fout, buffer);
+#endif
+  } else if (format == PAM) {
+    ok &= WebPWritePAM(fout, buffer);
+  } else if (format == PPM || format == RGB || format == BGR) {
+    ok &= WebPWritePPM(fout, buffer);
+  } else if (format == RGBA_4444 || format == RGB_565 || format == rgbA_4444) {
+    ok &= WebPWrite16bAsPGM(fout, buffer);
+  } else if (format == BMP) {
+    ok &= WebPWriteBMP(fout, buffer);
+  } else if (format == TIFF) {
+    ok &= WebPWriteTIFF(fout, buffer);
+  } else if (format == RAW_YUV) {
+    ok &= WebPWriteYUV(fout, buffer);
+  } else if (format == PGM || format == YUV || format == YUVA) {
+    ok &= WebPWritePGM(fout, buffer);
+  } else if (format == ALPHA_PLANE_ONLY) {
+    ok &= WebPWriteAlphaPlane(fout, buffer);
+  }
+  if (fout != NULL && fout != stdout) {
+    fclose(fout);
+  }
+  return ok;
+}

imageio/image_enc.h

@@ -0,0 +1,96 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  All-in-one library to save PNG/JPEG/WebP/TIFF/WIC images.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#ifndef WEBP_IMAGEIO_IMAGE_ENC_H_
+#define WEBP_IMAGEIO_IMAGE_ENC_H_
+
+#include <stdio.h>
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#include "webp/types.h"
+#include "webp/decode.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Output types
+typedef enum {
+  PNG = 0,
+  PAM,
+  PPM,
+  PGM,
+  BMP,
+  TIFF,
+  RAW_YUV,
+  ALPHA_PLANE_ONLY,  // this is for experimenting only
+  // forced colorspace output (for testing, mostly)
+  RGB, RGBA, BGR, BGRA, ARGB,
+  RGBA_4444, RGB_565,
+  rgbA, bgrA, Argb, rgbA_4444,
+  YUV, YUVA
+} WebPOutputFileFormat;
+
+// General all-purpose call.
+// Most formats expect a 'buffer' containing RGBA-like samples, except
+// RAW_YUV, YUV and YUVA formats.
+// If 'out_file_name' is "-", data is saved to stdout.
+// Returns false if an error occurred, true otherwise.
+int WebPSaveImage(const WebPDecBuffer* const buffer,
+                  WebPOutputFileFormat format, const char* const out_file_name);
+
+// Save to PNG.
+#ifdef HAVE_WINCODEC_H
+int WebPWritePNG(const char* out_file_name, int use_stdout,
+                 const struct WebPDecBuffer* const buffer);
+#else
+int WebPWritePNG(FILE* out_file, const WebPDecBuffer* const buffer);
+#endif
+
+// Save to PPM format (RGB, no alpha)
+int WebPWritePPM(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save to PAM format (= PPM + alpha)
+int WebPWritePAM(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save 16b mode (RGBA4444, RGB565, ...) for debugging purposes.
+int WebPWrite16bAsPGM(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save as BMP
+int WebPWriteBMP(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save as TIFF
+int WebPWriteTIFF(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save the ALPHA plane (only) as a PGM
+int WebPWriteAlphaPlane(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save as YUV samples as PGM format (using IMC4 layout).
+// See: https://www.fourcc.org/yuv.php#IMC4.
+// (very convenient format for viewing the samples, esp. for odd dimensions).
+int WebPWritePGM(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save YUV(A) planes sequentially (raw dump)
+int WebPWriteYUV(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+// Save 16b mode (RGBA4444, RGB565, ...) as PGM format, for debugging purposes.
+int WebPWrite16bAsPGM(FILE* fout, const struct WebPDecBuffer* const buffer);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_IMAGEIO_IMAGE_ENC_H_

imageio/imageio_util.c

@@ -0,0 +1,162 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  Utility functions used by the image decoders.
+//
+
+#include "./imageio_util.h"
+
+#if defined(_WIN32)
+#include <fcntl.h>   // for _O_BINARY
+#include <io.h>      // for _setmode()
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include "../examples/unicode.h"
+
+// -----------------------------------------------------------------------------
+// File I/O
+
+FILE* ImgIoUtilSetBinaryMode(FILE* file) {
+#if defined(_WIN32)
+  if (_setmode(_fileno(file), _O_BINARY) == -1) {
+    fprintf(stderr, "Failed to reopen file in O_BINARY mode.\n");
+    return NULL;
+  }
+#endif
+  return file;
+}
+
+int ImgIoUtilReadFromStdin(const uint8_t** data, size_t* data_size) {
+  static const size_t kBlockSize = 16384;  // default initial size
+  size_t max_size = 0;
+  size_t size = 0;
+  uint8_t* input = NULL;
+
+  if (data == NULL || data_size == NULL) return 0;
+  *data = NULL;
+  *data_size = 0;
+
+  if (!ImgIoUtilSetBinaryMode(stdin)) return 0;
+
+  while (!feof(stdin)) {
+    // We double the buffer size each time and read as much as possible.
+    const size_t extra_size = (max_size == 0) ? kBlockSize : max_size;
+    // we allocate one extra byte for the \0 terminator
+    void* const new_data = realloc(input, max_size + extra_size + 1);
+    if (new_data == NULL) goto Error;
+    input = (uint8_t*)new_data;
+    max_size += extra_size;
+    size += fread(input + size, 1, extra_size, stdin);
+    if (size < max_size) break;
+  }
+  if (ferror(stdin)) goto Error;
+  if (input != NULL) input[size] = '\0';  // convenient 0-terminator
+  *data = input;
+  *data_size = size;
+  return 1;
+
+ Error:
+  free(input);
+  fprintf(stderr, "Could not read from stdin\n");
+  return 0;
+}
+
+int ImgIoUtilReadFile(const char* const file_name,
+                      const uint8_t** data, size_t* data_size) {
+  int ok;
+  uint8_t* file_data;
+  size_t file_size;
+  FILE* in;
+  const int from_stdin = (file_name == NULL) || !WSTRCMP(file_name, "-");
+
+  if (from_stdin) return ImgIoUtilReadFromStdin(data, data_size);
+
+  if (data == NULL || data_size == NULL) return 0;
+  *data = NULL;
+  *data_size = 0;
+
+  in = WFOPEN(file_name, "rb");
+  if (in == NULL) {
+    WFPRINTF(stderr, "cannot open input file '%s'\n", (const W_CHAR*)file_name);
+    return 0;
+  }
+  fseek(in, 0, SEEK_END);
+  file_size = ftell(in);
+  fseek(in, 0, SEEK_SET);
+  // we allocate one extra byte for the \0 terminator
+  file_data = (uint8_t*)WebPMalloc(file_size + 1);
+  if (file_data == NULL) {
+    fclose(in);
+    WFPRINTF(stderr, "memory allocation failure when reading file %s\n",
+             (const W_CHAR*)file_name);
+    return 0;
+  }
+  ok = (fread(file_data, file_size, 1, in) == 1);
+  fclose(in);
+
+  if (!ok) {
+    WFPRINTF(stderr, "Could not read %d bytes of data from file %s\n",
+             (int)file_size, (const W_CHAR*)file_name);
+    WebPFree(file_data);
+    return 0;
+  }
+  file_data[file_size] = '\0';  // convenient 0-terminator
+  *data = file_data;
+  *data_size = file_size;
+  return 1;
+}
+
+// -----------------------------------------------------------------------------
+
+int ImgIoUtilWriteFile(const char* const file_name,
+                       const uint8_t* data, size_t data_size) {
+  int ok;
+  FILE* out;
+  const int to_stdout = (file_name == NULL) || !WSTRCMP(file_name, "-");
+
+  if (data == NULL) {
+    return 0;
+  }
+  out = to_stdout ? ImgIoUtilSetBinaryMode(stdout) : WFOPEN(file_name, "wb");
+  if (out == NULL) {
+    WFPRINTF(stderr, "Error! Cannot open output file '%s'\n",
+             (const W_CHAR*)file_name);
+    return 0;
+  }
+  ok = (fwrite(data, data_size, 1, out) == 1);
+  if (out != stdout) fclose(out);
+  return ok;
+}
+
+// -----------------------------------------------------------------------------
+
+void ImgIoUtilCopyPlane(const uint8_t* src, int src_stride,
+                        uint8_t* dst, int dst_stride, int width, int height) {
+  while (height-- > 0) {
+    memcpy(dst, src, width * sizeof(*dst));
+    src += src_stride;
+    dst += dst_stride;
+  }
+}
+
+// -----------------------------------------------------------------------------
+
+int ImgIoUtilCheckSizeArgumentsOverflow(uint64_t stride, size_t height) {
+  const uint64_t total_size = stride * height;
+  int ok = (total_size == (size_t)total_size);
+  // check that 'stride' is representable as int:
+  ok = ok && ((uint64_t)(int)stride == stride);
+#if defined(WEBP_MAX_IMAGE_SIZE)
+  ok = ok && (total_size <= (uint64_t)WEBP_MAX_IMAGE_SIZE);
+#endif
+  return ok;
+}
+
+// -----------------------------------------------------------------------------

imageio/imageio_util.h

@@ -0,0 +1,64 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+//  Utility functions used by the image decoders.
+//
+
+#ifndef WEBP_IMAGEIO_IMAGEIO_UTIL_H_
+#define WEBP_IMAGEIO_IMAGEIO_UTIL_H_
+
+#include <stdio.h>
+#include "webp/types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//------------------------------------------------------------------------------
+// File I/O
+
+// Reopen file in binary (O_BINARY) mode.
+// Returns 'file' on success, NULL otherwise.
+FILE* ImgIoUtilSetBinaryMode(FILE* file);
+
+// Allocates storage for entire file 'file_name' and returns contents and size
+// in 'data' and 'data_size'. Returns 1 on success, 0 otherwise. '*data' should
+// be deleted using WebPFree().
+// Note: for convenience, the data will be null-terminated with an extra byte
+// (not accounted for in *data_size), in case the file is text and intended
+// to be used as a C-string.
+// If 'file_name' is NULL or equal to "-", input is read from stdin by calling
+// the function ImgIoUtilReadFromStdin().
+int ImgIoUtilReadFile(const char* const file_name,
+                      const uint8_t** data, size_t* data_size);
+
+// Same as ImgIoUtilReadFile(), but reads until EOF from stdin instead.
+int ImgIoUtilReadFromStdin(const uint8_t** data, size_t* data_size);
+
+// Write a data segment into a file named 'file_name'. Returns true if ok.
+// If 'file_name' is NULL or equal to "-", output is written to stdout.
+int ImgIoUtilWriteFile(const char* const file_name,
+                       const uint8_t* data, size_t data_size);
+
+//------------------------------------------------------------------------------
+
+// Copy width x height pixels from 'src' to 'dst' honoring the strides.
+void ImgIoUtilCopyPlane(const uint8_t* src, int src_stride,
+                        uint8_t* dst, int dst_stride, int width, int height);
+
+//------------------------------------------------------------------------------
+
+// Returns 0 in case of overflow, memory over-allocation or excessive dimension.
+int ImgIoUtilCheckSizeArgumentsOverflow(uint64_t stride, size_t height);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_IMAGEIO_IMAGEIO_UTIL_H_

imageio/jpegdec.c

@@ -12,18 +12,20 @@
 #include "./jpegdec.h"
 
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include "webp/config.h"
 #endif
 
 #include <stdio.h>
 
 #ifdef WEBP_HAVE_JPEG
 #include <jpeglib.h>
+#include <jerror.h>
 #include <setjmp.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "webp/encode.h"
+#include "./imageio_util.h"
 #include "./metadata.h"
 
 // -----------------------------------------------------------------------------
@@ -204,37 +206,94 @@ struct my_error_mgr {
 
 static void my_error_exit(j_common_ptr dinfo) {
   struct my_error_mgr* myerr = (struct my_error_mgr*)dinfo->err;
+  fprintf(stderr, "libjpeg error: ");
   dinfo->err->output_message(dinfo);
   longjmp(myerr->setjmp_buffer, 1);
 }
 
-int ReadJPEG(FILE* in_file, WebPPicture* const pic, Metadata* const metadata) {
-  int ok = 0;
-  int stride, width, height;
-  struct jpeg_decompress_struct dinfo;
-  struct my_error_mgr jerr;
-  uint8_t* rgb = NULL;
-  JSAMPROW buffer[1];
+typedef struct {
+  struct jpeg_source_mgr pub;
+  const uint8_t* data;
+  size_t data_size;
+} JPEGReadContext;
 
+static void ContextInit(j_decompress_ptr cinfo) {
+  JPEGReadContext* const ctx = (JPEGReadContext*)cinfo->src;
+  ctx->pub.next_input_byte = ctx->data;
+  ctx->pub.bytes_in_buffer = ctx->data_size;
+}
+
+static boolean ContextFill(j_decompress_ptr cinfo) {
+  // we shouldn't get here.
+  ERREXIT(cinfo, JERR_FILE_READ);
+  return FALSE;
+}
+
+static void ContextSkip(j_decompress_ptr cinfo, long jump_size) {
+  JPEGReadContext* const ctx = (JPEGReadContext*)cinfo->src;
+  size_t jump = (size_t)jump_size;
+  if (jump > ctx->pub.bytes_in_buffer) {  // Don't overflow the buffer.
+    jump = ctx->pub.bytes_in_buffer;
+  }
+  ctx->pub.bytes_in_buffer -= jump;
+  ctx->pub.next_input_byte += jump;
+}
+
+static void ContextTerm(j_decompress_ptr cinfo) {
+  (void)cinfo;
+}
+
+static void ContextSetup(volatile struct jpeg_decompress_struct* const cinfo,
+                         JPEGReadContext* const ctx) {
+  cinfo->src = (struct jpeg_source_mgr*)ctx;
+  ctx->pub.init_source = ContextInit;
+  ctx->pub.fill_input_buffer = ContextFill;
+  ctx->pub.skip_input_data = ContextSkip;
+  ctx->pub.resync_to_restart = jpeg_resync_to_restart;
+  ctx->pub.term_source = ContextTerm;
+  ctx->pub.bytes_in_buffer = 0;
+  ctx->pub.next_input_byte = NULL;
+}
+
+int ReadJPEG(const uint8_t* const data, size_t data_size,
+             WebPPicture* const pic, int keep_alpha,
+             Metadata* const metadata) {
+  volatile int ok = 0;
+  int width, height;
+  int64_t stride;
+  volatile struct jpeg_decompress_struct dinfo;
+  struct my_error_mgr jerr;
+  uint8_t* volatile rgb = NULL;
+  JSAMPROW buffer[1];
+  JPEGReadContext ctx;
+
+  if (data == NULL || data_size == 0 || pic == NULL) return 0;
+
+  (void)keep_alpha;
+  memset(&ctx, 0, sizeof(ctx));
+  ctx.data = data;
+  ctx.data_size = data_size;
+
+  memset((j_decompress_ptr)&dinfo, 0, sizeof(dinfo));   // for setjmp safety
   dinfo.err = jpeg_std_error(&jerr.pub);
   jerr.pub.error_exit = my_error_exit;
 
   if (setjmp(jerr.setjmp_buffer)) {
  Error:
     MetadataFree(metadata);
-    jpeg_destroy_decompress(&dinfo);
+    jpeg_destroy_decompress((j_decompress_ptr)&dinfo);
     goto End;
   }
 
-  jpeg_create_decompress(&dinfo);
-  jpeg_stdio_src(&dinfo, in_file);
-  if (metadata != NULL) SaveMetadataMarkers(&dinfo);
-  jpeg_read_header(&dinfo, TRUE);
+  jpeg_create_decompress((j_decompress_ptr)&dinfo);
+  ContextSetup(&dinfo, &ctx);
+  if (metadata != NULL) SaveMetadataMarkers((j_decompress_ptr)&dinfo);
+  jpeg_read_header((j_decompress_ptr)&dinfo, TRUE);
 
   dinfo.out_color_space = JCS_RGB;
   dinfo.do_fancy_upsampling = TRUE;
 
-  jpeg_start_decompress(&dinfo);
+  jpeg_start_decompress((j_decompress_ptr)&dinfo);
 
   if (dinfo.output_components != 3) {
     goto Error;
@@ -242,47 +301,59 @@ int ReadJPEG(FILE* in_file, WebPPicture* const pic, Metadata* const metadata) {
 
   width = dinfo.output_width;
   height = dinfo.output_height;
-  stride = dinfo.output_width * dinfo.output_components * sizeof(*rgb);
+  stride = (int64_t)dinfo.output_width * dinfo.output_components * sizeof(*rgb);
 
-  rgb = (uint8_t*)malloc(stride * height);
+  if (stride != (int)stride ||
+      !ImgIoUtilCheckSizeArgumentsOverflow(stride, height)) {
+    goto Error;
+  }
+
+  rgb = (uint8_t*)malloc((size_t)stride * height);
   if (rgb == NULL) {
-    goto End;
+    goto Error;
   }
   buffer[0] = (JSAMPLE*)rgb;
 
   while (dinfo.output_scanline < dinfo.output_height) {
-    if (jpeg_read_scanlines(&dinfo, buffer, 1) != 1) {
-      goto End;
+    if (jpeg_read_scanlines((j_decompress_ptr)&dinfo, buffer, 1) != 1) {
+      goto Error;
     }
     buffer[0] += stride;
   }
 
   if (metadata != NULL) {
-    ok = ExtractMetadataFromJPEG(&dinfo, metadata);
+    ok = ExtractMetadataFromJPEG((j_decompress_ptr)&dinfo, metadata);
     if (!ok) {
       fprintf(stderr, "Error extracting JPEG metadata!\n");
       goto Error;
     }
   }
 
-  jpeg_finish_decompress(&dinfo);
-  jpeg_destroy_decompress(&dinfo);
+  jpeg_finish_decompress((j_decompress_ptr)&dinfo);
+  jpeg_destroy_decompress((j_decompress_ptr)&dinfo);
 
   // WebP conversion.
   pic->width = width;
   pic->height = height;
-  ok = WebPPictureImportRGB(pic, rgb, stride);
-  if (!ok) goto Error;
+  ok = WebPPictureImportRGB(pic, rgb, (int)stride);
+  if (!ok) {
+    pic->width = 0;   // WebPPictureImportRGB() barely touches 'pic' on failure.
+    pic->height = 0;  // Just reset dimensions but keep any 'custom_ptr' etc.
+    MetadataFree(metadata);  // In case the caller forgets to free it on error.
+  }
 
  End:
   free(rgb);
   return ok;
 }
 #else  // !WEBP_HAVE_JPEG
-int ReadJPEG(FILE* in_file, struct WebPPicture* const pic,
+int ReadJPEG(const uint8_t* const data, size_t data_size,
+             struct WebPPicture* const pic, int keep_alpha,
              struct Metadata* const metadata) {
-  (void)in_file;
+  (void)data;
+  (void)data_size;
   (void)pic;
+  (void)keep_alpha;
   (void)metadata;
   fprintf(stderr, "JPEG support not compiled. Please install the libjpeg "
           "development package before building.\n");

imageio/jpegdec.h

@@ -9,10 +9,9 @@
 //
 // JPEG decode.
 
-#ifndef WEBP_EXAMPLES_JPEGDEC_H_
-#define WEBP_EXAMPLES_JPEGDEC_H_
+#ifndef WEBP_IMAGEIO_JPEGDEC_H_
+#define WEBP_IMAGEIO_JPEGDEC_H_
 
-#include <stdio.h>
 #include "webp/types.h"
 
 #ifdef __cplusplus
@@ -22,14 +21,17 @@ extern "C" {
 struct Metadata;
 struct WebPPicture;
 
-// Reads a JPEG from 'in_file', returning the decoded output in 'pic'.
-// The output is RGB.
+// Reads a JPEG from 'data', returning the decoded output in 'pic'.
+// The output is RGB or YUV depending on pic->use_argb value.
 // Returns true on success.
-int ReadJPEG(FILE* in_file, struct WebPPicture* const pic,
+// 'keep_alpha' has no effect, but is kept for coherence with other signatures
+// for image readers.
+int ReadJPEG(const uint8_t* const data, size_t data_size,
+             struct WebPPicture* const pic, int keep_alpha,
              struct Metadata* const metadata);
 
 #ifdef __cplusplus
 }    // extern "C"
 #endif
 
-#endif  // WEBP_EXAMPLES_JPEGDEC_H_
+#endif  // WEBP_IMAGEIO_JPEGDEC_H_

imageio/metadata.h

@@ -10,8 +10,8 @@
 //  Metadata types and functions.
 //
 
-#ifndef WEBP_EXAMPLES_METADATA_H_
-#define WEBP_EXAMPLES_METADATA_H_
+#ifndef WEBP_IMAGEIO_METADATA_H_
+#define WEBP_IMAGEIO_METADATA_H_
 
 #include "webp/types.h"
 
@@ -44,4 +44,4 @@ int MetadataCopy(const char* metadata, size_t metadata_len,
 }    // extern "C"
 #endif
 
-#endif  // WEBP_EXAMPLES_METADATA_H_
+#endif  // WEBP_IMAGEIO_METADATA_H_

imageio/pngdec.c

@@ -12,25 +12,51 @@
 #include "./pngdec.h"
 
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include "webp/config.h"
 #endif
 
 #include <stdio.h>
 
 #ifdef WEBP_HAVE_PNG
+#ifndef PNG_USER_MEM_SUPPORTED
+#define PNG_USER_MEM_SUPPORTED  // for png_create_read_struct_2
+#endif
 #include <png.h>
 #include <setjmp.h>   // note: this must be included *after* png.h
 #include <stdlib.h>
 #include <string.h>
 
 #include "webp/encode.h"
+#include "./imageio_util.h"
 #include "./metadata.h"
 
+#define LOCAL_PNG_VERSION ((PNG_LIBPNG_VER_MAJOR << 8) | PNG_LIBPNG_VER_MINOR)
+#define LOCAL_PNG_PREREQ(maj, min) \
+   (LOCAL_PNG_VERSION >= (((maj) << 8) | (min)))
+
 static void PNGAPI error_function(png_structp png, png_const_charp error) {
   if (error != NULL) fprintf(stderr, "libpng error: %s\n", error);
   longjmp(png_jmpbuf(png), 1);
 }
 
+#if LOCAL_PNG_PREREQ(1,4)
+typedef png_alloc_size_t LocalPngAllocSize;
+#else
+typedef png_size_t LocalPngAllocSize;
+#endif
+
+static png_voidp MallocFunc(png_structp png_ptr, LocalPngAllocSize size) {
+  (void)png_ptr;
+  if (size != (size_t)size) return NULL;
+  if (!ImgIoUtilCheckSizeArgumentsOverflow(size, 1)) return NULL;
+  return (png_voidp)malloc((size_t)size);
+}
+
+static void FreeFunc(png_structp png_ptr, png_voidp ptr) {
+  (void)png_ptr;
+  free(ptr);
+}
+
 // Converts the NULL terminated 'hexstring' which contains 2-byte character
 // representations of hex values to raw data.
 // 'hexstring' may contain values consisting of [A-F][a-f][0-9] in pairs,
@@ -107,7 +133,7 @@ static const struct {
                  MetadataPayload* const payload);
   size_t storage_offset;
 } kPNGMetadataMap[] = {
-  // http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/PNG.html#TextualData
+  // https://exiftool.org/TagNames/PNG.html#TextualData
   // See also: ExifTool on CPAN.
   { "Raw profile type exif", ProcessRawProfile, METADATA_OFFSET(exif) },
   { "Raw profile type xmp",  ProcessRawProfile, METADATA_OFFSET(xmp) },
@@ -131,8 +157,8 @@ static int ExtractMetadataFromPNG(png_structp png,
   for (p = 0; p < 2; ++p)  {
     png_infop const info = (p == 0) ? head_info : end_info;
     png_textp text = NULL;
-    const int num = png_get_text(png, info, &text, NULL);
-    int i;
+    const png_uint_32 num = png_get_text(png, info, &text, NULL);
+    png_uint_32 i;
     // Look for EXIF / XMP metadata.
     for (i = 0; i < num; ++i, ++text) {
       int j;
@@ -170,11 +196,10 @@ static int ExtractMetadataFromPNG(png_structp png,
     {
       png_charp name;
       int comp_type;
-#if ((PNG_LIBPNG_VER_MAJOR << 8) | PNG_LIBPNG_VER_MINOR << 0) < \
-    ((1 << 8) | (5 << 0))
-      png_charp profile;
-#else  // >= libpng 1.5.0
+#if LOCAL_PNG_PREREQ(1,5)
       png_bytep profile;
+#else
+      png_charp profile;
 #endif
       png_uint_32 len;
 
@@ -184,43 +209,71 @@ static int ExtractMetadataFromPNG(png_structp png,
       }
     }
   }
-
   return 1;
 }
 
-int ReadPNG(FILE* in_file, WebPPicture* const pic, int keep_alpha,
-            Metadata* const metadata) {
-  png_structp png;
-  png_infop info = NULL;
-  png_infop end_info = NULL;
+typedef struct {
+  const uint8_t* data;
+  size_t data_size;
+  png_size_t offset;
+} PNGReadContext;
+
+static void ReadFunc(png_structp png_ptr, png_bytep data, png_size_t length) {
+  PNGReadContext* const ctx = (PNGReadContext*)png_get_io_ptr(png_ptr);
+  if (ctx->data_size - ctx->offset < length) {
+    png_error(png_ptr, "ReadFunc: invalid read length (overflow)!");
+  }
+  memcpy(data, ctx->data + ctx->offset, length);
+  ctx->offset += length;
+}
+
+int ReadPNG(const uint8_t* const data, size_t data_size,
+            struct WebPPicture* const pic,
+            int keep_alpha, struct Metadata* const metadata) {
+  volatile png_structp png = NULL;
+  volatile png_infop info = NULL;
+  volatile png_infop end_info = NULL;
+  PNGReadContext context = { NULL, 0, 0 };
   int color_type, bit_depth, interlaced;
   int has_alpha;
   int num_passes;
   int p;
-  int ok = 0;
+  volatile int ok = 0;
   png_uint_32 width, height, y;
-  int stride;
-  uint8_t* rgb = NULL;
+  int64_t stride;
+  uint8_t* volatile rgb = NULL;
 
-  png = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
-  if (png == NULL) {
-    goto End;
-  }
+  if (data == NULL || data_size == 0 || pic == NULL) return 0;
+
+  context.data = data;
+  context.data_size = data_size;
+
+  png = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL,
+                                 NULL, MallocFunc, FreeFunc);
+  if (png == NULL) goto End;
 
   png_set_error_fn(png, 0, error_function, NULL);
   if (setjmp(png_jmpbuf(png))) {
  Error:
     MetadataFree(metadata);
-    png_destroy_read_struct(&png, &info, &end_info);
     goto End;
   }
 
+#if LOCAL_PNG_PREREQ(1,5) || \
+    (LOCAL_PNG_PREREQ(1,4) && PNG_LIBPNG_VER_RELEASE >= 1)
+  // If it looks like the bitstream is going to need more memory than libpng's
+  // internal limit (default: 8M), try to (reasonably) raise it.
+  if (data_size > png_get_chunk_malloc_max(png) && data_size < (1u << 24)) {
+    png_set_chunk_malloc_max(png, data_size);
+  }
+#endif
+
   info = png_create_info_struct(png);
   if (info == NULL) goto Error;
   end_info = png_create_info_struct(png);
   if (end_info == NULL) goto Error;
 
-  png_init_io(png, in_file);
+  png_set_read_fn(png, &context, ReadFunc);
   png_read_info(png, info);
   if (!png_get_IHDR(png, info,
                     &width, &height, &bit_depth, &color_type, &interlaced,
@@ -228,7 +281,9 @@ int ReadPNG(FILE* in_file, WebPPicture* const pic, int keep_alpha,
 
   png_set_strip_16(png);
   png_set_packing(png);
-  if (color_type == PNG_COLOR_TYPE_PALETTE) png_set_palette_to_rgb(png);
+  if (color_type == PNG_COLOR_TYPE_PALETTE) {
+    png_set_palette_to_rgb(png);
+  }
   if (color_type == PNG_COLOR_TYPE_GRAY ||
       color_type == PNG_COLOR_TYPE_GRAY_ALPHA) {
     if (bit_depth < 8) {
@@ -243,6 +298,16 @@ int ReadPNG(FILE* in_file, WebPPicture* const pic, int keep_alpha,
     has_alpha = !!(color_type & PNG_COLOR_MASK_ALPHA);
   }
 
+  // Apply gamma correction if needed.
+  {
+    double image_gamma = 1 / 2.2, screen_gamma = 2.2;
+    int srgb_intent;
+    if (png_get_sRGB(png, info, &srgb_intent) ||
+        png_get_gAMA(png, info, &image_gamma)) {
+      png_set_gamma(png, screen_gamma, image_gamma);
+    }
+  }
+
   if (!keep_alpha) {
     png_set_strip_alpha(png);
     has_alpha = 0;
@@ -250,13 +315,20 @@ int ReadPNG(FILE* in_file, WebPPicture* const pic, int keep_alpha,
 
   num_passes = png_set_interlace_handling(png);
   png_read_update_info(png, info);
-  stride = (has_alpha ? 4 : 3) * width * sizeof(*rgb);
-  rgb = (uint8_t*)malloc(stride * height);
+
+  stride = (int64_t)(has_alpha ? 4 : 3) * width * sizeof(*rgb);
+  if (stride != (int)stride ||
+      !ImgIoUtilCheckSizeArgumentsOverflow(stride, height)) {
+    goto Error;
+  }
+
+  rgb = (uint8_t*)malloc((size_t)stride * height);
   if (rgb == NULL) goto Error;
   for (p = 0; p < num_passes; ++p) {
+    png_bytep row = rgb;
     for (y = 0; y < height; ++y) {
-      png_bytep row = rgb + y * stride;
       png_read_rows(png, &row, NULL, 1);
+      row += stride;
     }
   }
   png_read_end(png, end_info);
@@ -267,26 +339,29 @@ int ReadPNG(FILE* in_file, WebPPicture* const pic, int keep_alpha,
     goto Error;
   }
 
-  png_destroy_read_struct(&png, &info, &end_info);
-
-  pic->width = width;
-  pic->height = height;
-  pic->use_argb = 1;
-  ok = has_alpha ? WebPPictureImportRGBA(pic, rgb, stride)
-                 : WebPPictureImportRGB(pic, rgb, stride);
+  pic->width = (int)width;
+  pic->height = (int)height;
+  ok = has_alpha ? WebPPictureImportRGBA(pic, rgb, (int)stride)
+                 : WebPPictureImportRGB(pic, rgb, (int)stride);
 
   if (!ok) {
     goto Error;
   }
 
  End:
+  if (png != NULL) {
+    png_destroy_read_struct((png_structpp)&png,
+                            (png_infopp)&info, (png_infopp)&end_info);
+  }
   free(rgb);
   return ok;
 }
 #else  // !WEBP_HAVE_PNG
-int ReadPNG(FILE* in_file, struct WebPPicture* const pic, int keep_alpha,
-            struct Metadata* const metadata) {
-  (void)in_file;
+int ReadPNG(const uint8_t* const data, size_t data_size,
+            struct WebPPicture* const pic,
+            int keep_alpha, struct Metadata* const metadata) {
+  (void)data;
+  (void)data_size;
   (void)pic;
   (void)keep_alpha;
   (void)metadata;

imageio/pngdec.h

@@ -9,10 +9,10 @@
 //
 // PNG decode.
 
-#ifndef WEBP_EXAMPLES_PNGDEC_H_
-#define WEBP_EXAMPLES_PNGDEC_H_
+#ifndef WEBP_IMAGEIO_PNGDEC_H_
+#define WEBP_IMAGEIO_PNGDEC_H_
 
-#include <stdio.h>
+#include "webp/types.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -21,15 +21,17 @@ extern "C" {
 struct Metadata;
 struct WebPPicture;
 
-// Reads a PNG from 'in_file', returning the decoded output in 'pic'.
+// Reads a PNG from 'data', returning the decoded output in 'pic'.
+// Output is RGBA or YUVA, depending on pic->use_argb value.
 // If 'keep_alpha' is true and the PNG has an alpha channel, the output is RGBA
-// otherwise it will be RGB.
+// or YUVA. Otherwise, alpha channel is dropped and output is RGB or YUV.
 // Returns true on success.
-int ReadPNG(FILE* in_file, struct WebPPicture* const pic, int keep_alpha,
-            struct Metadata* const metadata);
+int ReadPNG(const uint8_t* const data, size_t data_size,
+            struct WebPPicture* const pic,
+            int keep_alpha, struct Metadata* const metadata);
 
 #ifdef __cplusplus
 }    // extern "C"
 #endif
 
-#endif  // WEBP_EXAMPLES_PNGDEC_H_
+#endif  // WEBP_IMAGEIO_PNGDEC_H_

imageio/pnmdec.c

@@ -0,0 +1,296 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// (limited) PNM decoder
+
+#include "./pnmdec.h"
+
+#include <assert.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "webp/encode.h"
+#include "./imageio_util.h"
+
+typedef enum {
+  WIDTH_FLAG      = 1 << 0,
+  HEIGHT_FLAG     = 1 << 1,
+  DEPTH_FLAG      = 1 << 2,
+  MAXVAL_FLAG     = 1 << 3,
+  TUPLE_FLAG      = 1 << 4,
+  ALL_NEEDED_FLAGS = WIDTH_FLAG | HEIGHT_FLAG | DEPTH_FLAG | MAXVAL_FLAG
+} PNMFlags;
+
+typedef struct {
+  const uint8_t* data;
+  size_t data_size;
+  int width, height;
+  int bytes_per_px;
+  int depth;          // 1 (grayscale), 2 (grayscale + alpha), 3 (rgb), 4 (rgba)
+  int max_value;
+  int type;           // 5, 6 or 7
+  int seen_flags;
+} PNMInfo;
+
+// -----------------------------------------------------------------------------
+// PNM decoding
+
+#define MAX_LINE_SIZE 1024
+static const size_t kMinPNMHeaderSize = 3;
+
+static size_t ReadLine(const uint8_t* const data, size_t off, size_t data_size,
+                       char out[MAX_LINE_SIZE + 1], size_t* const out_size) {
+  size_t i = 0;
+  *out_size = 0;
+ redo:
+  for (i = 0; i < MAX_LINE_SIZE && off < data_size; ++i) {
+    out[i] = data[off++];
+    if (out[i] == '\n') break;
+  }
+  if (off < data_size) {
+    if (i == 0) goto redo;         // empty line
+    if (out[0] == '#') goto redo;  // skip comment
+  }
+  out[i] = 0;   // safety sentinel
+  *out_size = i;
+  return off;
+}
+
+static size_t FlagError(const char flag[]) {
+  fprintf(stderr, "PAM header error: flags '%s' already seen.\n", flag);
+  return 0;
+}
+
+// inspired from http://netpbm.sourceforge.net/doc/pam.html
+static size_t ReadPAMFields(PNMInfo* const info, size_t off) {
+  char out[MAX_LINE_SIZE + 1];
+  size_t out_size;
+  int tmp;
+  int expected_depth = -1;
+  assert(info != NULL);
+  while (1) {
+    off = ReadLine(info->data, off, info->data_size, out, &out_size);
+    if (off == 0) return 0;
+    if (sscanf(out, "WIDTH %d", &tmp) == 1) {
+      if (info->seen_flags & WIDTH_FLAG) return FlagError("WIDTH");
+      info->seen_flags |= WIDTH_FLAG;
+      info->width = tmp;
+    } else if (sscanf(out, "HEIGHT %d", &tmp) == 1) {
+      if (info->seen_flags & HEIGHT_FLAG) return FlagError("HEIGHT");
+      info->seen_flags |= HEIGHT_FLAG;
+      info->height = tmp;
+    } else if (sscanf(out, "DEPTH %d", &tmp) == 1) {
+      if (info->seen_flags & DEPTH_FLAG) return FlagError("DEPTH");
+      info->seen_flags |= DEPTH_FLAG;
+      info->depth = tmp;
+    } else if (sscanf(out, "MAXVAL %d", &tmp) == 1) {
+      if (info->seen_flags & MAXVAL_FLAG) return FlagError("MAXVAL");
+      info->seen_flags |= MAXVAL_FLAG;
+      info->max_value = tmp;
+    } else if (!strcmp(out, "TUPLTYPE RGB_ALPHA")) {
+      expected_depth = 4;
+      info->seen_flags |= TUPLE_FLAG;
+    } else if (!strcmp(out, "TUPLTYPE RGB")) {
+      expected_depth = 3;
+      info->seen_flags |= TUPLE_FLAG;
+    } else if (!strcmp(out, "TUPLTYPE GRAYSCALE_ALPHA")) {
+      expected_depth = 2;
+      info->seen_flags |= TUPLE_FLAG;
+    } else if (!strcmp(out, "TUPLTYPE GRAYSCALE")) {
+      expected_depth = 1;
+      info->seen_flags |= TUPLE_FLAG;
+    } else if (!strcmp(out, "ENDHDR")) {
+      break;
+    } else {
+      static const char kEllipsis[] = " ...";
+      int i;
+      if (out_size > 20) sprintf(out + 20 - strlen(kEllipsis), kEllipsis);
+      for (i = 0; i < (int)strlen(out); ++i) {
+        // isprint() might trigger a "char-subscripts" warning if given a char.
+        if (!isprint((int)out[i])) out[i] = ' ';
+      }
+      fprintf(stderr, "PAM header error: unrecognized entry [%s]\n", out);
+      return 0;
+    }
+  }
+  if (!(info->seen_flags & ALL_NEEDED_FLAGS)) {
+    fprintf(stderr, "PAM header error: missing tags%s%s%s%s\n",
+            (info->seen_flags & WIDTH_FLAG) ? "" : " WIDTH",
+            (info->seen_flags & HEIGHT_FLAG) ? "" : " HEIGHT",
+            (info->seen_flags & DEPTH_FLAG) ? "" : " DEPTH",
+            (info->seen_flags & MAXVAL_FLAG) ? "" : " MAXVAL");
+    return 0;
+  }
+  if (expected_depth != -1 && info->depth != expected_depth) {
+    fprintf(stderr, "PAM header error: expected DEPTH %d but got DEPTH %d\n",
+            expected_depth, info->depth);
+    return 0;
+  }
+  return off;
+}
+
+static size_t ReadHeader(PNMInfo* const info) {
+  size_t off = 0;
+  char out[MAX_LINE_SIZE + 1];
+  size_t out_size;
+  if (info == NULL) return 0;
+  if (info->data == NULL || info->data_size < kMinPNMHeaderSize) return 0;
+
+  info->width = info->height = 0;
+  info->type = -1;
+  info->seen_flags = 0;
+  info->bytes_per_px = 0;
+  info->depth = 0;
+  info->max_value = 0;
+
+  off = ReadLine(info->data, off, info->data_size, out, &out_size);
+  if (off == 0 || sscanf(out, "P%d", &info->type) != 1) return 0;
+  if (info->type == 7) {
+    off = ReadPAMFields(info, off);
+  } else {
+    off = ReadLine(info->data, off, info->data_size, out, &out_size);
+    if (off == 0 || sscanf(out, "%d %d", &info->width, &info->height) != 2) {
+      return 0;
+    }
+    off = ReadLine(info->data, off, info->data_size, out, &out_size);
+    if (off == 0 || sscanf(out, "%d", &info->max_value) != 1) return 0;
+
+    // finish initializing missing fields
+    info->depth = (info->type == 5) ? 1 : 3;
+  }
+  // perform some basic numerical validation
+  if (info->width <= 0 || info->height <= 0 ||
+      info->type <= 0 || info->type >= 9 ||
+      info->depth <= 0 || info->depth > 4 ||
+      info->max_value <= 0 || info->max_value >= 65536) {
+    return 0;
+  }
+  info->bytes_per_px = info->depth * (info->max_value > 255 ? 2 : 1);
+  return off;
+}
+
+int ReadPNM(const uint8_t* const data, size_t data_size,
+            WebPPicture* const pic, int keep_alpha,
+            struct Metadata* const metadata) {
+  int ok = 0;
+  int i, j;
+  uint64_t stride, pixel_bytes, sample_size, depth;
+  uint8_t* rgb = NULL, *tmp_rgb;
+  size_t offset;
+  PNMInfo info;
+
+  info.data = data;
+  info.data_size = data_size;
+  offset = ReadHeader(&info);
+  if (offset == 0) {
+    fprintf(stderr, "Error parsing PNM header.\n");
+    goto End;
+  }
+
+  if (info.type < 5 || info.type > 7) {
+    fprintf(stderr, "Unsupported P%d PNM format.\n", info.type);
+    goto End;
+  }
+
+  // Some basic validations.
+  if (pic == NULL) goto End;
+  if (info.width > WEBP_MAX_DIMENSION || info.height > WEBP_MAX_DIMENSION) {
+    fprintf(stderr, "Invalid %dx%d dimension for PNM\n",
+                    info.width, info.height);
+    goto End;
+  }
+
+  pixel_bytes = (uint64_t)info.width * info.height * info.bytes_per_px;
+  if (data_size < offset + pixel_bytes) {
+    fprintf(stderr, "Truncated PNM file (P%d).\n", info.type);
+    goto End;
+  }
+  sample_size = (info.max_value > 255) ? 2 : 1;
+  // final depth
+  depth = (info.depth == 1 || info.depth == 3 || !keep_alpha) ? 3 : 4;
+  stride = depth * info.width;
+  if (stride != (size_t)stride ||
+      !ImgIoUtilCheckSizeArgumentsOverflow(stride, info.height)) {
+    goto End;
+  }
+
+  rgb = (uint8_t*)malloc((size_t)stride * info.height);
+  if (rgb == NULL) goto End;
+
+  // Convert input.
+  // We only optimize for the sample_size=1, max_value=255, depth=1 case.
+  tmp_rgb = rgb;
+  for (j = 0; j < info.height; ++j) {
+    const uint8_t* in = data + offset;
+    offset += info.bytes_per_px * info.width;
+    assert(offset <= data_size);
+    if (info.max_value == 255 && info.depth >= 3) {
+      // RGB or RGBA
+      if (info.depth == 3 || keep_alpha) {
+        memcpy(tmp_rgb, in, info.depth * info.width * sizeof(*in));
+      } else {
+        assert(info.depth == 4 && !keep_alpha);
+        for (i = 0; i < info.width; ++i) {
+          tmp_rgb[3 * i + 0] = in[4 * i + 0];
+          tmp_rgb[3 * i + 1] = in[4 * i + 1];
+          tmp_rgb[3 * i + 2] = in[4 * i + 2];
+        }
+      }
+    } else {
+      // Unoptimized case, we need to handle non-trivial operations:
+      //   * convert 16b to 8b (if max_value > 255)
+      //   * rescale to [0..255] range (if max_value != 255)
+      //   * drop the alpha channel (if keep_alpha is false)
+      const uint32_t round = info.max_value / 2;
+      int k = 0;
+      for (i = 0; i < info.width * info.depth; ++i) {
+        uint32_t v = (sample_size == 2) ? 256u * in[2 * i + 0] + in[2 * i + 1]
+                   : in[i];
+        if (info.max_value != 255) v = (v * 255u + round) / info.max_value;
+        if (v > 255u) v = 255u;
+        if (info.depth > 2) {
+          if (!keep_alpha && info.depth == 4 && (i % 4) == 3) {
+            // skip alpha
+          } else {
+            tmp_rgb[k] = v;
+            k += 1;
+          }
+        } else if (info.depth == 1 || (i % 2) == 0) {
+          tmp_rgb[k + 0] = tmp_rgb[k + 1] = tmp_rgb[k + 2] = v;
+          k += 3;
+        } else if (keep_alpha && info.depth == 2) {
+          tmp_rgb[k] = v;
+          k += 1;
+        } else {
+          // skip alpha
+        }
+      }
+    }
+    tmp_rgb += stride;
+  }
+
+  // WebP conversion.
+  pic->width = info.width;
+  pic->height = info.height;
+  ok = (depth == 4) ? WebPPictureImportRGBA(pic, rgb, (int)stride)
+                    : WebPPictureImportRGB(pic, rgb, (int)stride);
+  if (!ok) goto End;
+
+  ok = 1;
+ End:
+  free((void*)rgb);
+
+  (void)metadata;
+  (void)keep_alpha;
+  return ok;
+}
+
+// -----------------------------------------------------------------------------

imageio/pnmdec.h

@@ -0,0 +1,37 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// partial PNM format decoder (ppm/pgm)
+
+#ifndef WEBP_IMAGEIO_PNMDEC_H_
+#define WEBP_IMAGEIO_PNMDEC_H_
+
+#include "webp/types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct Metadata;
+struct WebPPicture;
+
+// Reads a PNM file from 'data', returning the decoded output in 'pic'.
+// The output is RGB or YUV depending on pic->use_argb value.
+// Returns true on success.
+// 'metadata' has no effect, but is kept for coherence with other signatures
+// for image readers.
+int ReadPNM(const uint8_t* const data, size_t data_size,
+            struct WebPPicture* const pic, int keep_alpha,
+            struct Metadata* const metadata);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_IMAGEIO_PNMDEC_H_

imageio/tiffdec.c

@@ -0,0 +1,293 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// TIFF decode.
+
+#include "./tiffdec.h"
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+
+#ifdef WEBP_HAVE_TIFF
+#include <tiffio.h>
+
+#include "webp/encode.h"
+#include "./imageio_util.h"
+#include "./metadata.h"
+
+static const struct {
+  ttag_t tag;
+  size_t storage_offset;
+} kTIFFMetadataMap[] = {
+  { TIFFTAG_ICCPROFILE, METADATA_OFFSET(iccp) },
+  { TIFFTAG_XMLPACKET,  METADATA_OFFSET(xmp) },
+  { 0, 0 },
+};
+
+// Returns true on success. The caller must use MetadataFree() on 'metadata' in
+// all cases.
+static int ExtractMetadataFromTIFF(TIFF* const tif, Metadata* const metadata) {
+  int i;
+  toff_t exif_ifd_offset;
+
+  for (i = 0; kTIFFMetadataMap[i].tag != 0; ++i) {
+    MetadataPayload* const payload =
+        (MetadataPayload*)((uint8_t*)metadata +
+                           kTIFFMetadataMap[i].storage_offset);
+    void* tag_data;
+    uint32_t tag_data_len;
+
+    if (TIFFGetField(tif, kTIFFMetadataMap[i].tag, &tag_data_len, &tag_data) &&
+        !MetadataCopy((const char*)tag_data, tag_data_len, payload)) {
+      return 0;
+    }
+  }
+
+  // TODO(jzern): To extract the raw EXIF directory some parsing of it would be
+  // necessary to determine the overall size. In addition, value offsets in
+  // individual directory entries may need to be updated as, depending on the
+  // type, they are file based.
+  // Exif 2.2 Section 4.6.2 Tag Structure
+  // TIFF Revision 6.0 Part 1 Section 2 TIFF Structure #Image File Directory
+  if (TIFFGetField(tif, TIFFTAG_EXIFIFD, &exif_ifd_offset)) {
+    fprintf(stderr, "Warning: EXIF extraction from TIFF is unsupported.\n");
+  }
+  return 1;
+}
+
+// Ad-hoc structure to supply read-from-memory functionalities.
+typedef struct {
+  const uint8_t* data;
+  toff_t size;
+  toff_t pos;
+} MyData;
+
+static int MyClose(thandle_t opaque) {
+  (void)opaque;
+  return 0;
+}
+
+static toff_t MySize(thandle_t opaque) {
+  const MyData* const my_data = (MyData*)opaque;
+  return my_data->size;
+}
+
+static toff_t MySeek(thandle_t opaque, toff_t offset, int whence) {
+  MyData* const my_data = (MyData*)opaque;
+  offset += (whence == SEEK_CUR) ? my_data->pos
+          : (whence == SEEK_SET) ? 0
+          : my_data->size;
+  if (offset > my_data->size) return (toff_t)-1;
+  my_data->pos = offset;
+  return offset;
+}
+
+static int MyMapFile(thandle_t opaque, void** base, toff_t* size) {
+  (void)opaque;
+  (void)base;
+  (void)size;
+  return 0;
+}
+static void MyUnmapFile(thandle_t opaque, void* base, toff_t size) {
+  (void)opaque;
+  (void)base;
+  (void)size;
+}
+
+static tsize_t MyRead(thandle_t opaque, void* dst, tsize_t size) {
+  MyData* const my_data = (MyData*)opaque;
+  if (my_data->pos + size > my_data->size) {
+    size = (tsize_t)(my_data->size - my_data->pos);
+  }
+  if (size > 0) {
+    memcpy(dst, my_data->data + my_data->pos, size);
+    my_data->pos += size;
+  }
+  return size;
+}
+
+// Unmultiply Argb data. Taken from dsp/alpha_processing
+// (we don't want to force a dependency to a libdspdec library).
+#define MFIX 24    // 24bit fixed-point arithmetic
+#define HALF ((1u << MFIX) >> 1)
+
+static uint32_t Unmult(uint8_t x, uint32_t mult) {
+  const uint32_t v = (x * mult + HALF) >> MFIX;
+  return (v > 255u) ? 255u : v;
+}
+
+static WEBP_INLINE uint32_t GetScale(uint32_t a) {
+  return (255u << MFIX) / a;
+}
+
+#undef MFIX
+#undef HALF
+
+static void MultARGBRow(uint8_t* ptr, int width) {
+  int x;
+  for (x = 0; x < width; ++x, ptr += 4) {
+    const uint32_t alpha = ptr[3];
+    if (alpha < 255) {
+      if (alpha == 0) {   // alpha == 0
+        ptr[0] = ptr[1] = ptr[2] = 0;
+      } else {
+        const uint32_t scale = GetScale(alpha);
+        ptr[0] = Unmult(ptr[0], scale);
+        ptr[1] = Unmult(ptr[1], scale);
+        ptr[2] = Unmult(ptr[2], scale);
+      }
+    }
+  }
+}
+
+int ReadTIFF(const uint8_t* const data, size_t data_size,
+             WebPPicture* const pic, int keep_alpha,
+             Metadata* const metadata) {
+  MyData my_data = { data, (toff_t)data_size, 0 };
+  TIFF* tif;
+  uint32_t image_width, image_height, tile_width, tile_height;
+  uint64_t stride;
+  uint16_t samples_per_px = 0;
+  uint16_t extra_samples = 0;
+  uint16_t* extra_samples_ptr = NULL;
+  uint32_t* raster;
+  int64_t alloc_size;
+  int ok = 0;
+  tdir_t dircount;
+
+  if (data == NULL || data_size == 0 || data_size > INT_MAX || pic == NULL) {
+    return 0;
+  }
+
+  tif = TIFFClientOpen("Memory", "r", &my_data,
+                       MyRead, MyRead, MySeek, MyClose,
+                       MySize, MyMapFile, MyUnmapFile);
+  if (tif == NULL) {
+    fprintf(stderr, "Error! Cannot parse TIFF file\n");
+    return 0;
+  }
+
+  dircount = TIFFNumberOfDirectories(tif);
+  if (dircount > 1) {
+    fprintf(stderr, "Warning: multi-directory TIFF files are not supported.\n"
+                    "Only the first will be used, %d will be ignored.\n",
+                    dircount - 1);
+  }
+  if (!TIFFGetFieldDefaulted(tif, TIFFTAG_SAMPLESPERPIXEL, &samples_per_px)) {
+    fprintf(stderr, "Error! Cannot retrieve TIFF samples-per-pixel info.\n");
+    goto End;
+  }
+  if (!(samples_per_px == 1 || samples_per_px == 3 || samples_per_px == 4)) {
+    goto End;  // not supported
+  }
+
+  if (!(TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &image_width) &&
+        TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &image_height))) {
+    fprintf(stderr, "Error! Cannot retrieve TIFF image dimensions.\n");
+    goto End;
+  }
+  stride = (uint64_t)image_width * sizeof(*raster);
+  if (!ImgIoUtilCheckSizeArgumentsOverflow(stride, image_height)) {
+    fprintf(stderr, "Error! TIFF image dimension (%d x %d) is too large.\n",
+            image_width, image_height);
+    goto End;
+  }
+
+  // According to spec, a tile can be bigger than the image. However it should
+  // be a multiple of 16 and not way too large, so check that it's not more
+  // than twice the image size, for dimensions above some arbitrary minimum
+  // 32. We also check that they respect WebP's dimension and memory limit.
+  // Note that a tile can be 6byte/px in some cases. Here we assume
+  // 4byte/px with sizeof(*raster), to be conservative.
+  if (TIFFGetField(tif, TIFFTAG_TILEWIDTH, &tile_width) &&
+      TIFFGetField(tif, TIFFTAG_TILELENGTH, &tile_height)) {
+    if ((tile_width > 32 && tile_width / 2 > image_width) ||
+        (tile_height > 32 && tile_height / 2 > image_height) ||
+        !ImgIoUtilCheckSizeArgumentsOverflow(
+            (uint64_t)tile_width * sizeof(*raster), tile_height)) {
+      fprintf(stderr, "Error! TIFF tile dimension (%d x %d) is too large.\n",
+              tile_width, tile_height);
+      goto End;
+    }
+  }
+
+  if (samples_per_px > 3 && !TIFFGetField(tif, TIFFTAG_EXTRASAMPLES,
+                                          &extra_samples, &extra_samples_ptr)) {
+    fprintf(stderr, "Error! Cannot retrieve TIFF ExtraSamples info.\n");
+    goto End;
+  }
+
+  // _Tiffmalloc uses a signed type for size.
+  alloc_size = (int64_t)(stride * image_height);
+  if (alloc_size < 0 || alloc_size != (tsize_t)alloc_size) goto End;
+
+  raster = (uint32_t*)_TIFFmalloc((tsize_t)alloc_size);
+  if (raster != NULL) {
+    if (TIFFReadRGBAImageOriented(tif, image_width, image_height, raster,
+                                  ORIENTATION_TOPLEFT, 1)) {
+      pic->width = image_width;
+      pic->height = image_height;
+      // TIFF data is ABGR
+#ifdef WORDS_BIGENDIAN
+      TIFFSwabArrayOfLong(raster, image_width * image_height);
+#endif
+      // if we have an alpha channel, we must un-multiply from rgbA to RGBA
+      if (extra_samples == 1 && extra_samples_ptr != NULL &&
+          extra_samples_ptr[0] == EXTRASAMPLE_ASSOCALPHA) {
+        uint32_t y;
+        uint8_t* tmp = (uint8_t*)raster;
+        for (y = 0; y < image_height; ++y) {
+          MultARGBRow(tmp, image_width);
+          tmp += stride;
+        }
+      }
+      ok = keep_alpha
+         ? WebPPictureImportRGBA(pic, (const uint8_t*)raster, (int)stride)
+         : WebPPictureImportRGBX(pic, (const uint8_t*)raster, (int)stride);
+    }
+    _TIFFfree(raster);
+  } else {
+    fprintf(stderr, "Error allocating TIFF RGBA memory!\n");
+  }
+
+  if (ok) {
+    if (metadata != NULL) {
+      ok = ExtractMetadataFromTIFF(tif, metadata);
+      if (!ok) {
+        fprintf(stderr, "Error extracting TIFF metadata!\n");
+        MetadataFree(metadata);
+        WebPPictureFree(pic);
+      }
+    }
+  }
+ End:
+  TIFFClose(tif);
+  return ok;
+}
+#else  // !WEBP_HAVE_TIFF
+int ReadTIFF(const uint8_t* const data, size_t data_size,
+             struct WebPPicture* const pic, int keep_alpha,
+             struct Metadata* const metadata) {
+  (void)data;
+  (void)data_size;
+  (void)pic;
+  (void)keep_alpha;
+  (void)metadata;
+  fprintf(stderr, "TIFF support not compiled. Please install the libtiff "
+          "development package before building.\n");
+  return 0;
+}
+#endif  // WEBP_HAVE_TIFF
+
+// -----------------------------------------------------------------------------

imageio/tiffdec.h

@@ -9,8 +9,10 @@
 //
 // TIFF decode.
 
-#ifndef WEBP_EXAMPLES_TIFFDEC_H_
-#define WEBP_EXAMPLES_TIFFDEC_H_
+#ifndef WEBP_IMAGEIO_TIFFDEC_H_
+#define WEBP_IMAGEIO_TIFFDEC_H_
+
+#include "webp/types.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -19,11 +21,12 @@ extern "C" {
 struct Metadata;
 struct WebPPicture;
 
-// Reads a TIFF from 'filename', returning the decoded output in 'pic'.
+// Reads a TIFF from 'data', returning the decoded output in 'pic'.
+// Output is RGBA or YUVA, depending on pic->use_argb value.
 // If 'keep_alpha' is true and the TIFF has an alpha channel, the output is RGBA
-// otherwise it will be RGB.
+// or YUVA. Otherwise, alpha channel is dropped and output is RGB or YUV.
 // Returns true on success.
-int ReadTIFF(const char* const filename,
+int ReadTIFF(const uint8_t* const data, size_t data_size,
              struct WebPPicture* const pic, int keep_alpha,
              struct Metadata* const metadata);
 
@@ -31,4 +34,4 @@ int ReadTIFF(const char* const filename,
 }    // extern "C"
 #endif
 
-#endif  // WEBP_EXAMPLES_TIFFDEC_H_
+#endif  // WEBP_IMAGEIO_TIFFDEC_H_

imageio/webpdec.c

@@ -0,0 +1,244 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebP decode.
+
+#ifdef HAVE_CONFIG_H
+#include "webp/config.h"
+#endif
+
+#include "./webpdec.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "webp/decode.h"
+#include "webp/demux.h"
+#include "webp/encode.h"
+#include "../examples/unicode.h"
+#include "./imageio_util.h"
+#include "./metadata.h"
+
+//------------------------------------------------------------------------------
+// WebP decoding
+
+static const char* const kStatusMessages[VP8_STATUS_NOT_ENOUGH_DATA + 1] = {
+  "OK", "OUT_OF_MEMORY", "INVALID_PARAM", "BITSTREAM_ERROR",
+  "UNSUPPORTED_FEATURE", "SUSPENDED", "USER_ABORT", "NOT_ENOUGH_DATA"
+};
+
+static void PrintAnimationWarning(const WebPDecoderConfig* const config) {
+  if (config->input.has_animation) {
+    fprintf(stderr,
+            "Error! Decoding of an animated WebP file is not supported.\n"
+            "       Use webpmux to extract the individual frames or\n"
+            "       vwebp to view this image.\n");
+  }
+}
+
+void PrintWebPError(const char* const in_file, int status) {
+  WFPRINTF(stderr, "Decoding of %s failed.\n", (const W_CHAR*)in_file);
+  fprintf(stderr, "Status: %d", status);
+  if (status >= VP8_STATUS_OK && status <= VP8_STATUS_NOT_ENOUGH_DATA) {
+    fprintf(stderr, "(%s)", kStatusMessages[status]);
+  }
+  fprintf(stderr, "\n");
+}
+
+int LoadWebP(const char* const in_file,
+             const uint8_t** data, size_t* data_size,
+             WebPBitstreamFeatures* bitstream) {
+  VP8StatusCode status;
+  WebPBitstreamFeatures local_features;
+  if (!ImgIoUtilReadFile(in_file, data, data_size)) return 0;
+
+  if (bitstream == NULL) {
+    bitstream = &local_features;
+  }
+
+  status = WebPGetFeatures(*data, *data_size, bitstream);
+  if (status != VP8_STATUS_OK) {
+    WebPFree((void*)*data);
+    *data = NULL;
+    *data_size = 0;
+    PrintWebPError(in_file, status);
+    return 0;
+  }
+  return 1;
+}
+
+//------------------------------------------------------------------------------
+
+VP8StatusCode DecodeWebP(const uint8_t* const data, size_t data_size,
+                         WebPDecoderConfig* const config) {
+  if (config == NULL) return VP8_STATUS_INVALID_PARAM;
+  PrintAnimationWarning(config);
+  return WebPDecode(data, data_size, config);
+}
+
+VP8StatusCode DecodeWebPIncremental(
+    const uint8_t* const data, size_t data_size,
+    WebPDecoderConfig* const config) {
+  VP8StatusCode status = VP8_STATUS_OK;
+  if (config == NULL) return VP8_STATUS_INVALID_PARAM;
+
+  PrintAnimationWarning(config);
+
+  // Decoding call.
+  {
+    WebPIDecoder* const idec = WebPIDecode(data, data_size, config);
+    if (idec == NULL) {
+      fprintf(stderr, "Failed during WebPIDecode().\n");
+      return VP8_STATUS_OUT_OF_MEMORY;
+    } else {
+      status = WebPIUpdate(idec, data, data_size);
+      WebPIDelete(idec);
+    }
+  }
+  return status;
+}
+
+// -----------------------------------------------------------------------------
+// Metadata
+
+static int ExtractMetadata(const uint8_t* const data, size_t data_size,
+                           Metadata* const metadata) {
+  WebPData webp_data = { data, data_size };
+  WebPDemuxer* const demux = WebPDemux(&webp_data);
+  WebPChunkIterator chunk_iter;
+  uint32_t flags;
+
+  if (demux == NULL) return 0;
+  assert(metadata != NULL);
+
+  flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
+
+  if ((flags & ICCP_FLAG) && WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter)) {
+    MetadataCopy((const char*)chunk_iter.chunk.bytes, chunk_iter.chunk.size,
+                 &metadata->iccp);
+    WebPDemuxReleaseChunkIterator(&chunk_iter);
+  }
+  if ((flags & EXIF_FLAG) && WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter)) {
+    MetadataCopy((const char*)chunk_iter.chunk.bytes, chunk_iter.chunk.size,
+                 &metadata->exif);
+    WebPDemuxReleaseChunkIterator(&chunk_iter);
+  }
+  if ((flags & XMP_FLAG) && WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter)) {
+    MetadataCopy((const char*)chunk_iter.chunk.bytes, chunk_iter.chunk.size,
+                 &metadata->xmp);
+    WebPDemuxReleaseChunkIterator(&chunk_iter);
+  }
+  WebPDemuxDelete(demux);
+  return 1;
+}
+
+// -----------------------------------------------------------------------------
+
+int ReadWebP(const uint8_t* const data, size_t data_size,
+             WebPPicture* const pic,
+             int keep_alpha, Metadata* const metadata) {
+  int ok = 0;
+  VP8StatusCode status = VP8_STATUS_OK;
+  WebPDecoderConfig config;
+  WebPDecBuffer* const output_buffer = &config.output;
+  WebPBitstreamFeatures* const bitstream = &config.input;
+
+  if (data == NULL || data_size == 0 || pic == NULL) return 0;
+
+  if (!WebPInitDecoderConfig(&config)) {
+    fprintf(stderr, "Library version mismatch!\n");
+    return 0;
+  }
+
+  status = WebPGetFeatures(data, data_size, bitstream);
+  if (status != VP8_STATUS_OK) {
+    PrintWebPError("input data", status);
+    return 0;
+  }
+
+  do {
+    const int has_alpha = keep_alpha && bitstream->has_alpha;
+    uint64_t stride;
+    pic->width = bitstream->width;
+    pic->height = bitstream->height;
+    if (pic->use_argb) {
+      stride = (uint64_t)bitstream->width * 4;
+    } else {
+      stride = (uint64_t)bitstream->width * (has_alpha ? 5 : 3) / 2;
+      pic->colorspace = has_alpha ? WEBP_YUV420A : WEBP_YUV420;
+    }
+
+    if (!ImgIoUtilCheckSizeArgumentsOverflow(stride, bitstream->height)) {
+      status = VP8_STATUS_OUT_OF_MEMORY;
+      break;
+    }
+
+    ok = WebPPictureAlloc(pic);
+    if (!ok) {
+      status = VP8_STATUS_OUT_OF_MEMORY;
+      break;
+    }
+    if (pic->use_argb) {
+#ifdef WORDS_BIGENDIAN
+      output_buffer->colorspace = MODE_ARGB;
+#else
+      output_buffer->colorspace = MODE_BGRA;
+#endif
+      output_buffer->u.RGBA.rgba = (uint8_t*)pic->argb;
+      output_buffer->u.RGBA.stride = pic->argb_stride * sizeof(uint32_t);
+      output_buffer->u.RGBA.size = output_buffer->u.RGBA.stride * pic->height;
+    } else {
+      output_buffer->colorspace = has_alpha ? MODE_YUVA : MODE_YUV;
+      output_buffer->u.YUVA.y = pic->y;
+      output_buffer->u.YUVA.u = pic->u;
+      output_buffer->u.YUVA.v = pic->v;
+      output_buffer->u.YUVA.a = has_alpha ? pic->a : NULL;
+      output_buffer->u.YUVA.y_stride = pic->y_stride;
+      output_buffer->u.YUVA.u_stride = pic->uv_stride;
+      output_buffer->u.YUVA.v_stride = pic->uv_stride;
+      output_buffer->u.YUVA.a_stride = has_alpha ? pic->a_stride : 0;
+      output_buffer->u.YUVA.y_size = pic->height * pic->y_stride;
+      output_buffer->u.YUVA.u_size = (pic->height + 1) / 2 * pic->uv_stride;
+      output_buffer->u.YUVA.v_size = (pic->height + 1) / 2 * pic->uv_stride;
+      output_buffer->u.YUVA.a_size = pic->height * pic->a_stride;
+    }
+    output_buffer->is_external_memory = 1;
+
+    status = DecodeWebP(data, data_size, &config);
+    ok = (status == VP8_STATUS_OK);
+    if (ok && !keep_alpha && pic->use_argb) {
+      // Need to wipe out the alpha value, as requested.
+      int x, y;
+      uint32_t* argb = pic->argb;
+      for (y = 0; y < pic->height; ++y) {
+        for (x = 0; x < pic->width; ++x) argb[x] |= 0xff000000u;
+        argb += pic->argb_stride;
+      }
+    }
+  } while (0);   // <- so we can 'break' out of the loop
+
+  if (status != VP8_STATUS_OK) {
+    PrintWebPError("input data", status);
+    ok = 0;
+  }
+
+  WebPFreeDecBuffer(output_buffer);
+
+  if (ok && metadata != NULL) {
+    ok = ExtractMetadata(data, data_size, metadata);
+    if (!ok) {
+      PrintWebPError("metadata", VP8_STATUS_BITSTREAM_ERROR);
+    }
+  }
+  if (!ok) WebPPictureFree(pic);
+  return ok;
+}
+
+// -----------------------------------------------------------------------------

imageio/webpdec.h

@@ -0,0 +1,67 @@
+// Copyright 2014 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// WebP decode.
+
+#ifndef WEBP_IMAGEIO_WEBPDEC_H_
+#define WEBP_IMAGEIO_WEBPDEC_H_
+
+#include "webp/decode.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct Metadata;
+struct WebPPicture;
+
+//------------------------------------------------------------------------------
+// WebP decoding
+
+// Prints an informative error message regarding decode failure of 'in_file'.
+// 'status' is treated as a VP8StatusCode and if valid will be printed as a
+// text string.
+void PrintWebPError(const char* const in_file, int status);
+
+// Reads a WebP from 'in_file', returning the contents and size in 'data' and
+// 'data_size'. If not NULL, 'bitstream' is populated using WebPGetFeatures().
+// Returns true on success.
+int LoadWebP(const char* const in_file,
+             const uint8_t** data, size_t* data_size,
+             WebPBitstreamFeatures* bitstream);
+
+// Decodes the WebP contained in 'data'.
+// 'config' is a structure previously initialized by WebPInitDecoderConfig().
+// 'config->output' should have the desired colorspace selected.
+// Returns the decoder status. On success 'config->output' will contain the
+// decoded picture.
+VP8StatusCode DecodeWebP(const uint8_t* const data, size_t data_size,
+                         WebPDecoderConfig* const config);
+
+// Same as DecodeWebP(), but using the incremental decoder.
+VP8StatusCode DecodeWebPIncremental(
+    const uint8_t* const data, size_t data_size,
+    WebPDecoderConfig* const config);
+
+//------------------------------------------------------------------------------
+
+// Decodes a WebP contained in 'data', returning the decoded output in 'pic'.
+// Output is RGBA or YUVA, depending on pic->use_argb value.
+// If 'keep_alpha' is true and the WebP has an alpha channel, the output is RGBA
+// or YUVA. Otherwise, alpha channel is dropped and output is RGB or YUV.
+// Returns true on success.
+int ReadWebP(const uint8_t* const data, size_t data_size,
+             struct WebPPicture* const pic,
+             int keep_alpha, struct Metadata* const metadata);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_IMAGEIO_WEBPDEC_H_

imageio/wicdec.c

@@ -12,10 +12,12 @@
 #include "./wicdec.h"
 
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include "webp/config.h"
 #endif
 
+#include <assert.h>
 #include <stdio.h>
+#include <string.h>
 
 #ifdef HAVE_WINCODEC_H
 #ifdef __MINGW32__
@@ -25,12 +27,16 @@
 #define COBJMACROS
 #define _WIN32_IE 0x500  // Workaround bug in shlwapi.h when compiling C++
                          // code with COBJMACROS.
+#include <ole2.h>  // CreateStreamOnHGlobal()
 #include <shlwapi.h>
+#include <tchar.h>
 #include <windows.h>
 #include <wincodec.h>
 
-#include "webp/encode.h"
+#include "../examples/unicode.h"
+#include "./imageio_util.h"
 #include "./metadata.h"
+#include "webp/encode.h"
 
 #define IFS(fn)                                                     \
   do {                                                              \
@@ -72,12 +78,44 @@ WEBP_DEFINE_GUID(GUID_WICPixelFormat32bppBGRA_,
 WEBP_DEFINE_GUID(GUID_WICPixelFormat32bppRGBA_,
                  0xf5c7ad2d, 0x6a8d, 0x43dd,
                  0xa7, 0xa8, 0xa2, 0x99, 0x35, 0x26, 0x1a, 0xe9);
+WEBP_DEFINE_GUID(GUID_WICPixelFormat64bppBGRA_,
+                 0x1562ff7c, 0xd352, 0x46f9,
+                 0x97, 0x9e, 0x42, 0x97, 0x6b, 0x79, 0x22, 0x46);
+WEBP_DEFINE_GUID(GUID_WICPixelFormat64bppRGBA_,
+                 0x6fddc324, 0x4e03, 0x4bfe,
+                 0xb1, 0x85, 0x3d, 0x77, 0x76, 0x8d, 0xc9, 0x16);
 
 static HRESULT OpenInputStream(const char* filename, IStream** stream) {
   HRESULT hr = S_OK;
-  IFS(SHCreateStreamOnFileA(filename, STGM_READ, stream));
+  if (!WSTRCMP(filename, "-")) {
+    const uint8_t* data = NULL;
+    size_t data_size = 0;
+    const int ok = ImgIoUtilReadFile(filename, &data, &data_size);
+    if (ok) {
+      HGLOBAL image = GlobalAlloc(GMEM_MOVEABLE, data_size);
+      if (image != NULL) {
+        void* const image_mem = GlobalLock(image);
+        if (image_mem != NULL) {
+          memcpy(image_mem, data, data_size);
+          GlobalUnlock(image);
+          IFS(CreateStreamOnHGlobal(image, TRUE, stream));
+        } else {
+          hr = E_FAIL;
+        }
+      } else {
+        hr = E_OUTOFMEMORY;
+      }
+      free((void*)data);
+    } else {
+      hr = E_FAIL;
+    }
+  } else {
+    IFS(SHCreateStreamOnFile((const LPTSTR)filename, STGM_READ, stream));
+  }
+
   if (FAILED(hr)) {
-    fprintf(stderr, "Error opening input file %s (%08lx)\n", filename, hr);
+    _ftprintf(stderr, _T("Error opening input file %s (%08lx)\n"),
+              (const LPTSTR)filename, hr);
   }
   return hr;
 }
@@ -96,7 +134,10 @@ static HRESULT ExtractICCP(IWICImagingFactory* const factory,
   IWICColorContext** color_contexts;
 
   IFS(IWICBitmapFrameDecode_GetColorContexts(frame, 0, NULL, &count));
-  if (FAILED(hr) || count == 0) return hr;
+  if (FAILED(hr) || count == 0) {
+    // Treat unsupported operation as a non-fatal error. See crbug.com/webp/506.
+    return (hr == WINCODEC_ERR_UNSUPPORTEDOPERATION) ? S_OK : hr;
+  }
 
   color_contexts = (IWICColorContext**)calloc(count, sizeof(*color_contexts));
   if (color_contexts == NULL) return E_OUTOFMEMORY;
@@ -109,6 +150,7 @@ static HRESULT ExtractICCP(IWICImagingFactory* const factory,
     IFS(IWICBitmapFrameDecode_GetColorContexts(frame,
                                                count, color_contexts,
                                                &num_color_contexts));
+    assert(FAILED(hr) || num_color_contexts <= count);
     for (i = 0; SUCCEEDED(hr) && i < num_color_contexts; ++i) {
       WICColorContextType type;
       IFS(IWICColorContext_GetType(color_contexts[i], &type));
@@ -116,7 +158,7 @@ static HRESULT ExtractICCP(IWICImagingFactory* const factory,
         UINT size;
         IFS(IWICColorContext_GetProfileBytes(color_contexts[i],
                                              0, NULL, &size));
-        if (size > 0) {
+        if (SUCCEEDED(hr) && size > 0) {
           iccp->bytes = (uint8_t*)malloc(size);
           if (iccp->bytes == NULL) {
             hr = E_OUTOFMEMORY;
@@ -194,7 +236,11 @@ static int HasAlpha(IWICImagingFactory* const factory,
     has_alpha = IsEqualGUID(MAKE_REFGUID(pixel_format),
                             MAKE_REFGUID(GUID_WICPixelFormat32bppRGBA_)) ||
                 IsEqualGUID(MAKE_REFGUID(pixel_format),
-                            MAKE_REFGUID(GUID_WICPixelFormat32bppBGRA_));
+                            MAKE_REFGUID(GUID_WICPixelFormat32bppBGRA_)) ||
+                IsEqualGUID(MAKE_REFGUID(pixel_format),
+                            MAKE_REFGUID(GUID_WICPixelFormat64bppRGBA_)) ||
+                IsEqualGUID(MAKE_REFGUID(pixel_format),
+                            MAKE_REFGUID(GUID_WICPixelFormat64bppBGRA_));
   }
   return has_alpha;
 }
@@ -227,14 +273,21 @@ int ReadPictureWithWIC(const char* const filename,
   WICPixelFormatGUID src_pixel_format = GUID_WICPixelFormatUndefined;
   const WICFormatImporter* importer = NULL;
   GUID src_container_format = GUID_NULL_;
+  // From Windows Kits\10\Include\10.0.19041.0\um\wincodec.h
+  WEBP_DEFINE_GUID(GUID_ContainerFormatWebp_,
+                   0xe094b0e2, 0x67f2, 0x45b3,
+                   0xb0, 0xea, 0x11, 0x53, 0x37, 0xca, 0x7c, 0xf3);
   static const GUID* kAlphaContainers[] = {
     &GUID_ContainerFormatBmp,
     &GUID_ContainerFormatPng,
     &GUID_ContainerFormatTiff,
+    &GUID_ContainerFormatWebp_,
     NULL
   };
   int has_alpha = 0;
-  int stride;
+  int64_t stride;
+
+  if (filename == NULL || pic == NULL) return 0;
 
   IFS(CoInitialize(NULL));
   IFS(CoCreateInstance(MAKE_REFGUID(CLSID_WICImagingFactory), NULL,
@@ -253,15 +306,21 @@ int ReadPictureWithWIC(const char* const filename,
           factory, stream, NULL,
           WICDecodeMetadataCacheOnDemand, &decoder));
   IFS(IWICBitmapDecoder_GetFrameCount(decoder, &frame_count));
-  if (SUCCEEDED(hr) && frame_count == 0) {
-    fprintf(stderr, "No frame found in input file.\n");
-    hr = E_FAIL;
+  if (SUCCEEDED(hr)) {
+    if (frame_count == 0) {
+      fprintf(stderr, "No frame found in input file.\n");
+      hr = E_FAIL;
+    } else if (frame_count > 1) {
+      // WIC will be tried before native WebP decoding so avoid duplicating the
+      // error message.
+      hr = E_FAIL;
+    }
   }
   IFS(IWICBitmapDecoder_GetFrame(decoder, 0, &frame));
   IFS(IWICBitmapFrameDecode_GetPixelFormat(frame, &src_pixel_format));
   IFS(IWICBitmapDecoder_GetContainerFormat(decoder, &src_container_format));
 
-  if (keep_alpha) {
+  if (SUCCEEDED(hr) && keep_alpha) {
     const GUID** guid;
     for (guid = kAlphaContainers; *guid != NULL; ++guid) {
       if (IsEqualGUID(MAKE_REFGUID(src_container_format),
@@ -294,22 +353,27 @@ int ReadPictureWithWIC(const char* const filename,
 
   // Decode.
   IFS(IWICFormatConverter_GetSize(converter, &width, &height));
-  stride = importer->bytes_per_pixel * width * sizeof(*rgb);
+  stride = (int64_t)importer->bytes_per_pixel * width * sizeof(*rgb);
+  if (stride != (int)stride ||
+      !ImgIoUtilCheckSizeArgumentsOverflow(stride, height)) {
+    hr = E_FAIL;
+  }
+
   if (SUCCEEDED(hr)) {
-    rgb = (BYTE*)malloc(stride * height);
+    rgb = (BYTE*)malloc((size_t)stride * height);
     if (rgb == NULL)
       hr = E_OUTOFMEMORY;
   }
   IFS(IWICFormatConverter_CopyPixels(converter, NULL,
-                                     stride, stride * height, rgb));
+                                     (UINT)stride, (UINT)stride * height, rgb));
 
   // WebP conversion.
   if (SUCCEEDED(hr)) {
     int ok;
     pic->width = width;
     pic->height = height;
-    pic->use_argb = 1;
-    ok = importer->import(pic, rgb, stride);
+    pic->use_argb = 1;    // For WIC, we always force to argb
+    ok = importer->import(pic, rgb, (int)stride);
     if (!ok) hr = E_FAIL;
   }
   if (SUCCEEDED(hr)) {

imageio/wicdec.h

@@ -9,8 +9,8 @@
 //
 // Windows Imaging Component (WIC) decode.
 
-#ifndef WEBP_EXAMPLES_WICDEC_H_
-#define WEBP_EXAMPLES_WICDEC_H_
+#ifndef WEBP_IMAGEIO_WICDEC_H_
+#define WEBP_IMAGEIO_WICDEC_H_
 
 #ifdef __cplusplus
 extern "C" {
@@ -21,7 +21,7 @@ struct WebPPicture;
 
 // Reads an image from 'filename', returning the decoded output in 'pic'.
 // If 'keep_alpha' is true and the image has an alpha channel, the output is
-// RGBA otherwise it will be RGB.
+// RGBA otherwise it will be RGB. pic->use_argb is always forced to true.
 // Returns true on success.
 int ReadPictureWithWIC(const char* const filename,
                        struct WebPPicture* const pic, int keep_alpha,
@@ -31,4 +31,4 @@ int ReadPictureWithWIC(const char* const filename,
 }    // extern "C"
 #endif
 
-#endif  // WEBP_EXAMPLES_WICDEC_H_
+#endif  // WEBP_IMAGEIO_WICDEC_H_

infra/common.sh

@@ -0,0 +1,106 @@
+# Copyright (c) 2021, Google Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#   * Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#
+#   * Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+#
+#   * Neither the name of Google nor the names of its contributors may
+#     be used to endorse or promote products derived from this software
+#     without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+log_err() {
+  echo "[$(date +'%Y-%m-%dT%H:%M:%S%z')]: $*" >&2
+}
+
+#######################################
+# Create build directory. Build directory will be deleted if it exists.
+# Arguments:
+#   None.
+# Returns:
+#   mkdir result.
+#######################################
+make_build_dir() {
+  if [[ "$#" -ne 1 ]]; then
+    return 1
+  fi
+
+  local build_dir
+  build_dir="$1"
+  rm -rf "${build_dir}"
+  mkdir -p "${build_dir}"
+}
+
+#######################################
+# Cleanup files from the build directory.
+# Globals:
+#   LIBWEBP_ROOT repository's root path.
+# Arguments:
+#   $1 build directory.
+#######################################
+cleanup() {
+  # $1 is not completely removed to allow for binary artifacts to be
+  # extracted.
+  find "${1:?"Build directory not defined"}" \
+    \( -name "*.[ao]" -o -name "*.l[ao]" \) -exec rm -f {} +
+}
+
+#######################################
+# Setup ccache for toolchain.
+# Globals:
+#   PATH
+# Arguments:
+#   None.
+#######################################
+setup_ccache() {
+  if [[ -x "$(command -v ccache)" ]]; then
+    export CCACHE_CPP2=yes
+    export PATH="/usr/lib/ccache:${PATH}"
+  fi
+}
+
+#######################################
+# Detects whether test block should be run in the current test shard.
+# Globals:
+#   TEST_TOTAL_SHARDS: Valid range: [1, N]. Defaults to 1.
+#   TEST_SHARD_INDEX: Valid range: [0, TEST_TOTAL_SHARDS). Defaults to 0.
+#   libwebp_test_id: current test number; incremented with each call.
+# Arguments:
+#   None
+# Returns:
+#   true if the shard is active
+#   false if the shard is inactive
+#######################################
+shard_should_run() {
+  TEST_TOTAL_SHARDS=${TEST_TOTAL_SHARDS:=1}
+  TEST_SHARD_INDEX=${TEST_SHARD_INDEX:=0}
+  libwebp_test_id=${libwebp_test_id:=-1}
+  : $((libwebp_test_id += 1))
+
+  if [[ "${TEST_SHARD_INDEX}" -lt 0 ||
+    "${TEST_SHARD_INDEX}" -ge "${TEST_TOTAL_SHARDS}" ]]; then
+    log_err "Invalid TEST_SHARD_INDEX (${TEST_SHARD_INDEX})!" \
+      "Expected [0, ${TEST_TOTAL_SHARDS})."
+  fi
+
+  [[ "$((libwebp_test_id % TEST_TOTAL_SHARDS))" -eq "${TEST_SHARD_INDEX}" ]]
+}

infra/compile.sh

@@ -0,0 +1,401 @@
+#!/bin/bash
+# Copyright (c) 2021, Google Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#   * Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#
+#   * Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+#
+#   * Neither the name of Google nor the names of its contributors may
+#     be used to endorse or promote products derived from this software
+#     without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+set -xe
+LIBWEBP_ROOT="$(realpath "$(dirname "$0")/..")"
+WORKSPACE=${WORKSPACE:-"$(mktemp -d -t webp.XXX)"}
+
+# shellcheck source=infra/common.sh
+source "${LIBWEBP_ROOT}/infra/common.sh"
+
+usage() {
+  cat << EOF
+Usage: compile.sh BUILD_TYPE TARGET
+Options:
+BUILD_TYPE  supported build type: (shared, static, static-debug)
+TARGET      supported target platforms:
+              aarch64-linux-clang
+              aarch64-linux-gnu
+              arm-linux-gnueabi
+              arm-neon-linux-gnueabi
+              cmake
+              cmake-aarch64
+              cmake-arm
+              cmake-clang
+              disable-near-lossless
+              disable-sse4.1
+              disable-stats
+              force-aligned-32
+              force-aligned-64
+              gradle
+              i686-linux-asan
+              i686-linux-clang
+              i686-linux-gnu
+              i686-w64-mingw32
+              mips2el-linux-gnu
+              mips32dspr2el-linux-gnu
+              mips32eb-linux-gnu
+              mips32el-linux-gnu
+              mips32r2el-linux-gnu
+              mips32r5el-linux-gnu
+              mips64r2el-linux-gnu
+              mips64r6el-linux-gnu
+              native
+              reduce-csp
+              reduce-size
+              reduce-size-disable-stats
+              visibility-default-gnu
+              visibility-hidden-clang
+              visibility-hidden-gnu
+              wasm
+              x86_64-linux-clang
+              x86_64-linux-gnu
+              x86_64-linux-msan
+              x86_64-w64-mingw32
+Environment variables:
+WORKSPACE   directory where the build is done
+EOF
+}
+
+################################################################################
+echo "Building libwebp in ${WORKSPACE}"
+
+if [[ ! -d "${WORKSPACE}" ]]; then
+  log_err "${WORKSPACE} directory does not exist"
+  exit 1
+fi
+
+BUILD_TYPE=${1:?"Build type not defined.$(
+  echo
+  usage
+)"}
+TARGET=${2:?"Target not defined.$(
+  echo
+  usage
+)"}
+readonly BUILD_DIR="${WORKSPACE}/build-${BUILD_TYPE}"
+
+trap 'cleanup ${BUILD_DIR}' EXIT
+make_build_dir "${BUILD_DIR}"
+
+config_flags=()
+case "${BUILD_TYPE}" in
+  shared*) ;;  # Valid BUILD_TYPE but no setup required
+  static*) config_flags+=("--disable-shared") ;;
+  experimental) config_flags+=("--enable-experimental") ;;
+  *)
+    log_err "Invalid BUILD_TYPE"
+    usage
+    exit 1
+    ;;
+esac
+
+if grep -m 1 -q "enable-asserts" "${LIBWEBP_ROOT}/configure.ac"; then
+  config_flags+=("--enable-asserts")
+fi
+
+case "${TARGET}" in
+  aarch64-linux-clang)
+    TARGET="aarch64-linux-gnu"
+    CC="clang"
+    CC="${CC} --target=aarch64-linux-gnu"
+    export CC
+    export CFLAGS="-isystem /usr/aarch64-linux-gnu/include"
+    ;;
+  arm-linux-gnueabi)
+    export CFLAGS="-O3 -march=armv7-a -mfloat-abi=softfp -ftree-vectorize"
+    ;;
+  arm-neon-linux-gnueabi)
+    TARGET="arm-linux-gnueabi"
+    CFLAGS="-O3 -march=armv7-a -mfpu=neon -mfloat-abi=softfp -ftree-vectorize"
+    export CFLAGS
+    ;;
+  mips2el-linux-gnu)
+    export CFLAGS="-EL -O2 -mips2"
+    TARGET="mipsel-linux-gnu"
+    ;;
+  mips32el-linux-gnu)
+    export CFLAGS="-EL -O2 -mips32"
+    TARGET="mipsel-linux-gnu"
+    ;;
+  mips32r2el-linux-gnu)
+    export CFLAGS="-EL -O2 -mips32r2"
+    TARGET="mipsel-linux-gnu"
+    ;;
+  mips32dspr2el-linux-gnu)
+    export CFLAGS="-EL -O2 -mdspr2"
+    TARGET="mipsel-linux-gnu"
+    ;;
+  mips32r5el-linux-gnu)
+    export CFLAGS="-EL -O2 -mips32r5 -mmsa"
+    TARGET="mipsel-linux-gnu"
+    ;;
+  mips32eb-linux-gnu)
+    export CFLAGS="-EB -O2 -mips32"
+    TARGET="mips-linux-gnu"
+    ;;
+  mips64r2el-linux-gnu)
+    export CFLAGS="-EL -O2 -mips64r2 -mabi=64"
+    TARGET="mips64el-linux-gnuabi64"
+    ;;
+  mips64r6el-linux-gnu)
+    export CFLAGS="-EL -O2 -mips64r6 -mabi=64 -mmsa"
+    TARGET="mips-img-linux-gnu"
+    ;;
+  i686-linux-gnu)
+    export CC="gcc -m32"
+    ;;
+  i686-linux-clang)
+    TARGET="i686-linux-gnu"
+    export CC="clang -m32"
+    ;;
+  i686-linux-asan)
+    TARGET="i686-linux-gnu"
+    export CC="clang -m32 -fsanitize=address"
+    ;;
+  i686-linux-msan)
+    TARGET="i686-linux-gnu"
+    export CC="clang -m32 -fsanitize=memory"
+    ;;
+  x86_64-linux-clang)
+    TARGET="x86_64-linux-gnu"
+    export CC=clang
+    ;;
+  x86_64-linux-msan)
+    TARGET="x86_64-linux-gnu"
+    export CC="clang -fsanitize=memory"
+    ;;
+  force-aligned-32)
+    config_flags+=("--enable-aligned")
+    TARGET="i686-linux-gnu"
+    export CC="gcc -m32"
+    ;;
+  force-aligned-64)
+    config_flags+=("--enable-aligned")
+    TARGET="x86_64-linux-gnu"
+    ;;
+  visibility-default-*)
+    export CFLAGS="-O2 -g -fvisibility=default"
+    TARGET="x86_64-linux-gnu"
+    ;;
+  visibility-hidden-*)
+    export CFLAGS="-O2 -g -fvisibility=hidden"
+    if [[ "${TARGET}" = "visibility-hidden-clang" ]]; then
+      export CC=clang
+    fi
+    TARGET="x86_64-linux-gnu"
+    ;;
+  disable-sse4.1)
+    grep "${TARGET}" "${LIBWEBP_ROOT}/configure.ac" || exit 0
+    config_flags+=("--${TARGET}")
+    TARGET="x86_64-linux-gnu"
+    ;;
+  disable-near-lossless)
+    grep "${TARGET}" "${LIBWEBP_ROOT}/configure.ac" || exit 0
+    config_flags+=("--${TARGET}")
+    TARGET="x86_64-linux-gnu"
+    ;;
+  disable-stats)
+    git -C "${LIBWEBP_ROOT}" grep WEBP_DISABLE_STATS || exit 0
+    export CFLAGS="-O2 -g -DWEBP_DISABLE_STATS"
+    TARGET="x86_64-linux-gnu"
+    ;;
+  reduce-size)
+    git -C "${LIBWEBP_ROOT}" grep WEBP_REDUCE_SIZE || exit 0
+    export CFLAGS="-O2 -g -DWEBP_REDUCE_SIZE"
+    TARGET="x86_64-linux-gnu"
+    ;;
+  reduce-size-disable-stats)
+    git -C "${LIBWEBP_ROOT}" grep -e WEBP_DISABLE_STATS -e WEBP_REDUCE_SIZE \
+      || exit 0
+    export CFLAGS="-O2 -g -DWEBP_DISABLE_STATS -DWEBP_REDUCE_SIZE"
+    TARGET="x86_64-linux-gnu"
+    ;;
+  reduce-csp)
+    git -C "${LIBWEBP_ROOT}" grep WEBP_REDUCE_CSP || exit 0
+    export CFLAGS="-O2 -g -DWEBP_REDUCE_CSP"
+    TARGET="x86_64-linux-gnu"
+    ;;
+  x86_64-linux-gnu | *mingw32 | aarch64*) ;;  # Default target configuration
+  # non-configure based builds
+  native)
+    setup_ccache
+    # exercise makefile.unix then quit
+    make -C "${LIBWEBP_ROOT}" -f makefile.unix -j all
+    for tgt in extras examples/anim_diff; do
+      grep -q -m 1 "${tgt}" "${LIBWEBP_ROOT}/makefile.unix" \
+        && make -C "${LIBWEBP_ROOT}" -f makefile.unix -j "${tgt}"
+    done
+    [[ -d "${LIBWEBP_ROOT}/tests/fuzzer" ]] \
+      && make -j -C "${LIBWEBP_ROOT}/tests/fuzzer" -f makefile.unix
+    exit 0
+    ;;
+  cmake*)
+    setup_ccache
+    # exercise cmake then quit
+    opts=()
+    case "${TARGET}" in
+      cmake-clang)
+        opts+=("-DCMAKE_C_COMPILER=clang")
+        ;;
+      cmake-arm)
+        opts+=("-DCMAKE_C_COMPILER=arm-linux-gnueabi-gcc")
+        case "${GERRIT_BRANCH:-}" in
+          portable-intrinsics | 0.6.1) exit 0 ;;
+          *) ;;  # Skip configuration
+        esac
+        ;;
+      cmake-aarch64)
+        opts+=("-DCMAKE_C_COMPILER=aarch64-linux-gnu-gcc")
+        case "${GERRIT_BRANCH:-}" in
+          portable-intrinsics | 0.6.1) exit 0 ;;
+          *) ;;  # Skip configuration
+        esac
+        ;;
+      *) ;;  # Skip configuration
+    esac
+    case "${BUILD_TYPE}" in
+      static*)
+        opts+=("-DBUILD_SHARED_LIBS=OFF")
+        ;;
+      experimental)
+        opts+=("-DWEBP_EXPERIMENTAL_FEATURES=ON" "-DBUILD_SHARED_LIBS=ON")
+        ;;
+      *)
+        opts+=("-DBUILD_SHARED_LIBS=ON")
+        ;;
+    esac
+    case "${BUILD_TYPE}" in
+      *debug) opts+=("-DCMAKE_BUILD_TYPE=Debug") ;;
+      *) opts+=("-DCMAKE_BUILD_TYPE=RelWithDebInfo") ;;
+    esac
+    cd "${BUILD_DIR}"
+    opts+=("-DWEBP_BUILD_CWEBP=ON" "-DWEBP_BUILD_DWEBP=ON")
+    grep -m 1 -q WEBP_BUILD_GIF2WEBP "${LIBWEBP_ROOT}/CMakeLists.txt" \
+      && opts+=("-DWEBP_BUILD_GIF2WEBP=ON")
+    grep -m 1 -q WEBP_BUILD_IMG2WEBP "${LIBWEBP_ROOT}/CMakeLists.txt" \
+      && opts+=("-DWEBP_BUILD_IMG2WEBP=ON")
+    cmake "${opts[@]}" "${LIBWEBP_ROOT}"
+    make VERBOSE=1 -j
+    case "${BUILD_TYPE}" in
+      static)
+        mkdir -p examples
+        cp [cd]webp examples
+        ;;
+      *) ;;  # Skip configuration.
+    esac
+
+    grep "install" "${LIBWEBP_ROOT}/CMakeLists.txt" || exit 0
+
+    make DESTDIR="${BUILD_DIR}/webp-install" install/strip
+    mkdir tmp
+    cd tmp
+    cat > CMakeLists.txt << EOF
+cmake_minimum_required(VERSION 2.8.7)
+
+project(libwebp C)
+
+find_package(WebP)
+if (NOT WebP_FOUND)
+  message(FATAL_ERROR "WebP package not found")
+endif ()
+message("WebP_FOUND: \${WebP_FOUND}")
+message("WebP_INCLUDE_DIRS: \${WebP_INCLUDE_DIRS}")
+message("WebP_LIBRARIES: \${WebP_LIBRARIES}")
+message("WEBP_INCLUDE_DIRS: \${WEBP_INCLUDE_DIRS}")
+message("WEBP_LIBRARIES: \${WEBP_LIBRARIES}")
+EOF
+    cmake . "${opts[@]}" \
+      "-DCMAKE_PREFIX_PATH=${BUILD_DIR}/webp-install/usr/local"
+    exit 0
+    ;;
+  gradle)
+    setup_ccache
+    # exercise gradle then quit
+    [[ -f "${LIBWEBP_ROOT}/gradlew" ]] || exit 0
+
+    cd "${BUILD_DIR}"
+    # TODO -g / --gradle-user-home could be used if there's a race between jobs
+    "${LIBWEBP_ROOT}/gradlew" -p "${LIBWEBP_ROOT}" buildAllExecutables
+    exit 0
+    ;;
+  wasm)
+    grep -m 1 -q WEBP_ENABLE_WASM "${LIBWEBP_ROOT}/CMakeLists.txt" || exit 0
+    opts+=("-DCMAKE_C_COMPILER=clang" "-DWEBP_ENABLE_WASM=ON")
+    opts+=("-DWEBP_BUILD_CWEBP=ON" "-DWEBP_BUILD_DWEBP=ON")
+    case "${BUILD_TYPE}" in
+      *debug) opts+=("-DCMAKE_BUILD_TYPE=Debug") ;;
+      *) opts+=("-DCMAKE_BUILD_TYPE=RelWithDebInfo") ;;
+    esac
+    cd "${BUILD_DIR}"
+    cmake "${opts[@]}" "${LIBWEBP_ROOT}"
+    make VERBOSE=1 -j
+    mkdir examples
+    case "${BUILD_TYPE}" in
+      static)
+        mkdir -p examples
+        cp [cd]webp examples
+        ;;
+      *) ;;  # Skip configuration
+    esac
+    exit 0
+    ;;
+  *)
+    log_err "Invalid TARGET"
+    usage
+    exit 1
+    ;;
+esac
+
+case "${TARGET}" in
+  *mingw32) ;;  # Skip configuration
+  *)
+    case "${TARGET}-${CC}" in
+      static-debug-gcc* | static-debug-)
+        CFLAGS="${CFLAGS} -fprofile-arcs -ftest-coverage -O0 -g"
+        CXXFLAGS="${CXXFLAGS} -fprofile-arcs -ftest-coverage -O0 -g"
+        export CFLAGS CXXFLAGS
+        ;;
+      *) ;;  # This case should not be reached.
+    esac
+    ;;
+esac
+
+setup_ccache
+
+cd "${LIBWEBP_ROOT}"
+./autogen.sh
+
+cd "${BUILD_DIR}"
+"${LIBWEBP_ROOT}/configure" \
+  --host "${TARGET}" --build "$("${LIBWEBP_ROOT}/config.guess")" \
+  --enable-everything "${config_flags[@]}"
+make -j V=1

infra/compile_android.sh

@@ -0,0 +1,224 @@
+#!/bin/bash
+# Copyright (c) 2021, Google Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#   * Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#
+#   * Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+#
+#   * Neither the name of Google nor the names of its contributors may
+#     be used to endorse or promote products derived from this software
+#     without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+set -xe
+LIBWEBP_ROOT="$(realpath "$(dirname "$0")/..")"
+readonly LIBWEBP_ROOT
+readonly WORKSPACE=${WORKSPACE:-"$(mktemp -d -t webp.android.XXX)"}
+# shellcheck source=infra/common.sh
+source "${LIBWEBP_ROOT}/infra/common.sh"
+
+usage() {
+  cat << EOF
+Usage: $(basename "$0") BUILD_TYPE APP_ABI
+Options:
+BUILD_TYPE  supported build types:
+              static
+              static-debug
+              shared
+              shared-debug
+APP_ABI     supported application binary interfaces:
+              armeabi-v7a
+              arm64-v8a
+              x86
+              x86_64
+Environment variables:
+WORKSPACE   directory where the build is done.
+ANDROID_NDK_DIR directory where the android ndk tools are.
+EOF
+}
+
+################################################################################
+echo "Building libwebp for Android in ${WORKSPACE}"
+
+if [[ ! -d "${WORKSPACE}" ]]; then
+  log_err "${WORKSPACE} directory does not exist."
+  exit 1
+fi
+
+readonly BUILD_TYPE=${1:?"BUILD_TYPE is not defined.$(
+  echo
+  usage
+)"}
+readonly APP_ABI=${2:?"APP_ABI not defined.$(
+  echo
+  usage
+)"}
+readonly ANDROID_NDK_DIR=${ANDROID_NDK_DIR:?"ANDROID_NDK_DIR is not defined.$(
+  echo
+  usage
+)"}
+readonly BUILD_DIR="${WORKSPACE}/build-${BUILD_TYPE}"
+readonly STANDALONE_ANDROID_DIR="${WORKSPACE}/android"
+
+if [[ ! -x "${ANDROID_NDK_DIR}/ndk-build" ]]; then
+  log_err "unable to find ndk-build in ANDROID_NDK_DIR: ${ANDROID_NDK_DIR}."
+  exit 1
+fi
+
+CFLAGS=
+LDFLAGS=
+opts=()
+case "${BUILD_TYPE}" in
+  *debug)
+    readonly APP_OPTIM="debug"
+    CFLAGS="-O0 -g"
+    opts+=("--enable-asserts")
+    ;;
+  static* | shared*)
+    readonly APP_OPTIM="release"
+    CFLAGS="-O2 -g"
+    ;;
+  *)
+    usage
+    exit 1
+    ;;
+esac
+
+case "${BUILD_TYPE}" in
+  shared*) readonly SHARED="1" ;;
+  *)
+    readonly SHARED="0"
+    CFLAGS="${CFLAGS} -fPIE"
+    LDFLAGS="${LDFLAGS} -Wl,-pie"
+    opts+=("--disable-shared")
+    ;;
+esac
+
+# Create a fresh build directory
+make_build_dir "${BUILD_DIR}"
+cd "${BUILD_DIR}"
+ln -s "${LIBWEBP_ROOT}" jni
+
+"${ANDROID_NDK_DIR}/ndk-build" -j2 \
+  APP_ABI="${APP_ABI}" \
+  APP_OPTIM="${APP_OPTIM}" \
+  ENABLE_SHARED="${SHARED}"
+
+cd "${LIBWEBP_ROOT}"
+./autogen.sh
+
+case "${APP_ABI}" in
+  armeabi*) arch="arm" ;;
+  arm64*) arch="arm64" ;;
+  *) arch="${APP_ABI}" ;;
+esac
+# TODO(b/185520507): remove this and use the binaries from
+# toolchains/llvm/prebuilt/ directly.
+rm -rf "${STANDALONE_ANDROID_DIR}"
+"${ANDROID_NDK_DIR}/build/tools/make_standalone_toolchain.py" \
+  --api 24 --arch "${arch}" --stl gnustl --install-dir \
+  "${STANDALONE_ANDROID_DIR}"
+export PATH="${STANDALONE_ANDROID_DIR}/bin:${PATH}"
+
+rm -rf "${BUILD_DIR}"
+make_build_dir "${BUILD_DIR}"
+cd "${BUILD_DIR}"
+
+case "${arch}" in
+  arm)
+    host="arm-linux-androideabi"
+    case "${APP_ABI}" in
+      armeabi) ;;
+      armeabi-v7a)
+        CFLAGS="${CFLAGS} -march=armv7-a -mfpu=neon -mfloat-abi=softfp"
+        ;;
+      *) ;;  # No configuration needed
+    esac
+    ;;
+  arm64)
+    host="aarch64-linux-android"
+    ;;
+  x86)
+    host="i686-linux-android"
+    ;;
+  x86_64)
+    host="x86_64-linux-android"
+    ;;
+  *) ;;  # Skip configuration
+esac
+
+setup_ccache
+CC="clang"
+
+"${LIBWEBP_ROOT}/configure" --host "${host}" --build \
+  "$("${LIBWEBP_ROOT}/config.guess")" CC="${CC}" CFLAGS="${CFLAGS}" \
+  LDFLAGS="${LDFLAGS}" "${opts[@]}"
+make -j
+
+if [[ "${GERRIT_REFSPEC:-}" = "refs/heads/portable-intrinsics" ]] \
+  || [[ "${GERRIT_BRANCH:-}" = "portable-intrinsics" ]]; then
+  cd "${WORKSPACE}"
+  rm -rf build && mkdir build
+  cd build
+  standalone="${WORKSPACE}/android"
+  cmake ../libwebp \
+    -DWEBP_BUILD_DWEBP=1 \
+    -DCMAKE_C_COMPILER="${standalone}/bin/clang" \
+    -DCMAKE_PREFIX_PATH="${standalone}/sysroot/usr/lib" \
+    -DCMAKE_C_FLAGS=-fPIE \
+    -DCMAKE_EXE_LINKER_FLAGS=-Wl,-pie \
+    -DCMAKE_BUILD_TYPE=Release \
+    -DWEBP_ENABLE_WASM=1
+  make -j2
+
+  cd "${WORKSPACE}"
+  make_build_dir "${BUILD_DIR}"
+  cd "${BUILD_DIR}"
+  case "${APP_ABI}" in
+    armeabi-v7a | arm64*)
+      cmake "${LIBWEBP_ROOT}" \
+        -DWEBP_BUILD_DWEBP=1 \
+        -DCMAKE_C_COMPILER="${standalone}/bin/clang" \
+        -DCMAKE_PREFIX_PATH="${standalone}/sysroot/usr/lib" \
+        -DCMAKE_C_FLAGS='-fPIE -DENABLE_NEON_BUILTIN_MULHI_INT16X8' \
+        -DCMAKE_EXE_LINKER_FLAGS=-Wl,-pie \
+        -DCMAKE_BUILD_TYPE=Release \
+        -DWEBP_ENABLE_WASM=1
+      make -j2
+      ;;
+    x86*)
+      cmake "${LIBWEBP_ROOT}" \
+        -DWEBP_BUILD_DWEBP=1 \
+        -DCMAKE_C_COMPILER="${standalone}/bin/clang" \
+        -DCMAKE_PREFIX_PATH="${standalone}/sysroot/usr/lib" \
+        -DCMAKE_C_FLAGS='-fPIE -DENABLE_X86_BUILTIN_MULHI_INT16X8' \
+        -DCMAKE_EXE_LINKER_FLAGS=-Wl,-pie \
+        -DCMAKE_BUILD_TYPE=Release \
+        -DWEBP_ENABLE_WASM=1
+      make -j2
+      ;;
+    *)
+      log_err "APP_ABI not supported."
+      exit 1
+      ;;
+  esac
+fi

infra/compile_js.sh

@@ -0,0 +1,75 @@
+#!/bin/bash
+# Copyright (c) 2021, Google Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#   * Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#
+#   * Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+#
+#   * Neither the name of Google nor the names of its contributors may
+#     be used to endorse or promote products derived from this software
+#     without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+set -ex
+
+readonly WORKSPACE="${WORKSPACE:-"$(mktemp -d -t webp.js.XXX)"}"
+readonly BUILD_DIR="${WORKSPACE}/webp_js/"
+readonly LIBWEBP_ROOT="$(realpath "$(dirname "$0")/..")"
+
+# shellcheck source=infra/common.sh
+source "${LIBWEBP_ROOT}/infra/common.sh"
+
+usage() {
+  cat << EOF
+Usage: $(basename "$0")
+Environment variables:
+WORKSPACE directory where the build is done
+EMSDK_DIR directory where emsdk is installed
+EOF
+}
+
+[[ -d "${EMSDK_DIR:?Not defined}" ]] \
+  || (log_err "${EMSDK_DIR} is not a valid directory." && exit 1)
+
+# shellcheck source=/opt/emsdk/emsdk_env.sh
+source "${EMSDK_DIR}/emsdk_env.sh"
+
+readonly EMSCRIPTEN=${EMSCRIPTEN:-"${EMSDK}/upstream/emscripten"}
+readonly \
+  EMSCRIPTEN_CMAKE_FILE="${EMSCRIPTEN}/cmake/Modules/Platform/Emscripten.cmake"
+make_build_dir "${BUILD_DIR}"
+
+pushd "${BUILD_DIR}"
+opts=("-GUnix Makefiles" "-DWEBP_BUILD_WEBP_JS=ON")
+if [[ -z "$(command -v emcmake)" ]]; then
+  opts+=("-DCMAKE_TOOLCHAIN_FILE=${EMSCRIPTEN_CMAKE_FILE}")
+  cmake \
+    "${opts[@]}" \
+    "${LIBWEBP_ROOT}"
+  make -j
+else
+  emcmake cmake \
+    "${opts[@]}" \
+    "${LIBWEBP_ROOT}"
+  emmake make -j
+fi
+popd

infra/run_static_analysis.sh

@@ -0,0 +1,98 @@
+#!/bin/bash
+# Copyright (c) 2021, Google Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#   * Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#
+#   * Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in
+#     the documentation and/or other materials provided with the
+#     distribution.
+#
+#   * Neither the name of Google nor the names of its contributors may
+#     be used to endorse or promote products derived from this software
+#     without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+set -xe
+
+LIBWEBP_ROOT="$(realpath "$(dirname "$0")/..")"
+readonly LIBWEBP_ROOT
+readonly WORKSPACE=${WORKSPACE:-"$(mktemp -d -t webp.scanbuild.XXX)"}
+
+# shellcheck source=infra/common.sh
+source "${LIBWEBP_ROOT}/infra/common.sh"
+
+usage() {
+  cat << EOF
+Usage: $(basename "$0") MODE
+Options:
+MODE supported scan modes: (shallow|deep)
+Environment variables:
+WORKSPACE directory where the build is done.
+EOF
+}
+
+#######################################
+# Wrap clang-tools scan-build.
+# Globals:
+#   OUTPUT_DIR target directory where scan-build report is generated.
+#   MODE scan-build mode
+# Arguments:
+#   $* scan-build additional args.
+# Returns:
+#   scan-build retcode
+#######################################
+scan_build() {
+  scan-build -o "${OUTPUT_DIR}" --use-analyzer="$(command -v clang)" \
+    -analyzer-config mode="${MODE}" "$*"
+}
+
+MODE=${1:?"MODE is not specified.$(
+  echo
+  usage
+)"}
+
+readonly OUTPUT_DIR="${WORKSPACE}/output-${MODE}"
+readonly BUILD_DIR="${WORKSPACE}/build"
+
+make_build_dir "${OUTPUT_DIR}"
+make_build_dir "${BUILD_DIR}"
+
+cd "${LIBWEBP_ROOT}"
+./autogen.sh
+
+cd "${BUILD_DIR}"
+grep -m 1 -q 'enable-asserts' "${LIBWEBP_ROOT}/configure.ac" \
+    && args='--enable-asserts'
+scan_build "${LIBWEBP_ROOT}/configure" --enable-everything "${args}"
+scan_build make -j4
+
+index="$(find "${OUTPUT_DIR}" -name index.html)"
+if [[ -f "${index}" ]]; then
+  mv "$(dirname "${index}")/"* "${OUTPUT_DIR}"
+else
+  # make a empty report to wipe out any old bug reports.
+  cat << EOT > "${OUTPUT_DIR}/index.html"
+<html>
+<body>
+No bugs reported.
+</body>
+</html>
+EOT
+fi

iosbuild.sh

@@ -1,56 +1,104 @@
 #!/bin/bash
 #
-# This script generates 'WebP.framework'. An iOS app can decode WebP images
-# by including 'WebP.framework'.
+# This script generates 'WebP.framework' and 'WebPDecoder.framework',
+# 'WebPDemux.framework' and 'WebPMux.framework'.
+# An iOS app can decode WebP images by including 'WebPDecoder.framework' and
+# both encode and decode WebP images by including 'WebP.framework'.
 #
-# Run ./iosbuild.sh to generate 'WebP.framework' under the current directory
-# (previous build will be erased if it exists).
+# Run ./iosbuild.sh to generate the frameworks under the current directory
+# (the previous build will be erased if it exists).
 #
 # This script is inspired by the build script written by Carson McDonald.
-# (http://www.ioncannon.net/programming/1483/using-webp-to-reduce-native-ios-app-size/).
+# (https://www.ioncannon.net/programming/1483/using-webp-to-reduce-native-ios-app-size/).
 
 set -e
 
+# Set this variable based on the desired minimum deployment target.
+readonly IOS_MIN_VERSION=6.0
+
 # Extract the latest SDK version from the final field of the form: iphoneosX.Y
-declare -r SDK=$(xcodebuild -showsdks \
+readonly SDK=$(xcodebuild -showsdks \
   | grep iphoneos | sort | tail -n 1 | awk '{print substr($NF, 9)}'
 )
 # Extract Xcode version.
-declare -r XCODE=$(xcodebuild -version | grep Xcode | cut -d " " -f2)
+readonly XCODE=$(xcodebuild -version | grep Xcode | cut -d " " -f2)
+if [[ -z "${XCODE}" ]]; then
+  echo "Xcode not available"
+  exit 1
+fi
 
-declare -r OLDPATH=${PATH}
+readonly OLDPATH=${PATH}
 
 # Add iPhoneOS-V6 to the list of platforms below if you need armv6 support.
 # Note that iPhoneOS-V6 support is not available with the iOS6 SDK.
-declare -r PLATFORMS="iPhoneSimulator iPhoneOS-V7 iPhoneOS-V7s"
-declare -r SRCDIR=$(dirname $0)
-declare -r TOPDIR=$(pwd)
-declare -r BUILDDIR="${TOPDIR}/iosbuild"
-declare -r TARGETDIR="${TOPDIR}/WebP.framework"
-declare -r DEVELOPER=$(xcode-select --print-path)
-declare -r PLATFORMSROOT="${DEVELOPER}/Platforms"
-declare -r LIPO=$(xcrun -sdk iphoneos${SDK} -find lipo)
+PLATFORMS="iPhoneSimulator iPhoneSimulator64"
+PLATFORMS+=" iPhoneOS-V7 iPhoneOS-V7s iPhoneOS-V7-arm64"
+readonly PLATFORMS
+readonly SRCDIR=$(dirname $0)
+readonly TOPDIR=$(pwd)
+readonly BUILDDIR="${TOPDIR}/iosbuild"
+readonly TARGETDIR="${TOPDIR}/WebP.framework"
+readonly DECTARGETDIR="${TOPDIR}/WebPDecoder.framework"
+readonly MUXTARGETDIR="${TOPDIR}/WebPMux.framework"
+readonly DEMUXTARGETDIR="${TOPDIR}/WebPDemux.framework"
+readonly DEVELOPER=$(xcode-select --print-path)
+readonly PLATFORMSROOT="${DEVELOPER}/Platforms"
+readonly LIPO=$(xcrun -sdk iphoneos${SDK} -find lipo)
 LIBLIST=''
+DECLIBLIST=''
+MUXLIBLIST=''
+DEMUXLIBLIST=''
 
 if [[ -z "${SDK}" ]]; then
   echo "iOS SDK not available"
   exit 1
-elif [[ ${SDK} < 4.0 ]]; then
-  echo "You need iOS SDK version 4.0 or above"
+elif [[ ${SDK%%.*} -gt 8 ]]; then
+  EXTRA_CFLAGS="-fembed-bitcode"
+elif [[ ${SDK%%.*} -le 6 ]]; then
+  echo "You need iOS SDK version 6.0 or above"
   exit 1
-else
-  echo "iOS SDK Version ${SDK}"
 fi
 
-rm -rf ${BUILDDIR}
-rm -rf ${TARGETDIR}
-mkdir -p ${BUILDDIR}
-mkdir -p ${TARGETDIR}/Headers/
+echo "Xcode Version: ${XCODE}"
+echo "iOS SDK Version: ${SDK}"
 
-[[ -e ${SRCDIR}/configure ]] || (cd ${SRCDIR} && sh autogen.sh)
+if [[ -e "${BUILDDIR}" || -e "${TARGETDIR}" || -e "${DECTARGETDIR}" \
+      || -e "${MUXTARGETDIR}" || -e "${DEMUXTARGETDIR}" ]]; then
+  cat << EOF
+WARNING: The following directories will be deleted:
+WARNING:   ${BUILDDIR}
+WARNING:   ${TARGETDIR}
+WARNING:   ${DECTARGETDIR}
+WARNING:   ${MUXTARGETDIR}
+WARNING:   ${DEMUXTARGETDIR}
+WARNING: The build will continue in 5 seconds...
+EOF
+  sleep 5
+fi
+rm -rf ${BUILDDIR} ${TARGETDIR} ${DECTARGETDIR} \
+    ${MUXTARGETDIR} ${DEMUXTARGETDIR}
+mkdir -p ${BUILDDIR} ${TARGETDIR}/Headers/ ${DECTARGETDIR}/Headers/ \
+    ${MUXTARGETDIR}/Headers/ ${DEMUXTARGETDIR}/Headers/
+
+if [[ ! -e ${SRCDIR}/configure ]]; then
+  if ! (cd ${SRCDIR} && sh autogen.sh); then
+    cat << EOF
+Error creating configure script!
+This script requires the autoconf/automake and libtool to build. MacPorts can
+be used to obtain these:
+https://www.macports.org/install.php
+EOF
+    exit 1
+  fi
+fi
 
 for PLATFORM in ${PLATFORMS}; do
-  if [[ "${PLATFORM}" == "iPhoneOS-V7s" ]]; then
+  ARCH2=""
+  if [[ "${PLATFORM}" == "iPhoneOS-V7-arm64" ]]; then
+    PLATFORM="iPhoneOS"
+    ARCH="aarch64"
+    ARCH2="arm64"
+  elif [[ "${PLATFORM}" == "iPhoneOS-V7s" ]]; then
     PLATFORM="iPhoneOS"
     ARCH="armv7s"
   elif [[ "${PLATFORM}" == "iPhoneOS-V7" ]]; then
@@ -59,6 +107,9 @@ for PLATFORM in ${PLATFORMS}; do
   elif [[ "${PLATFORM}" == "iPhoneOS-V6" ]]; then
     PLATFORM="iPhoneOS"
     ARCH="armv6"
+  elif [[ "${PLATFORM}" == "iPhoneSimulator64" ]]; then
+    PLATFORM="iPhoneSimulator"
+    ARCH="x86_64"
   else
     ARCH="i386"
   fi
@@ -66,43 +117,52 @@ for PLATFORM in ${PLATFORMS}; do
   ROOTDIR="${BUILDDIR}/${PLATFORM}-${SDK}-${ARCH}"
   mkdir -p "${ROOTDIR}"
 
-  SDKROOT="${PLATFORMSROOT}/${PLATFORM}.platform/Developer/SDKs/${PLATFORM}${SDK}.sdk/"
-  CFLAGS="-arch ${ARCH} -pipe -isysroot ${SDKROOT}"
-  LDFLAGS="-arch ${ARCH} -pipe -isysroot ${SDKROOT}"
+  DEVROOT="${DEVELOPER}/Toolchains/XcodeDefault.xctoolchain"
+  SDKROOT="${PLATFORMSROOT}/"
+  SDKROOT+="${PLATFORM}.platform/Developer/SDKs/${PLATFORM}${SDK}.sdk/"
+  CFLAGS="-arch ${ARCH2:-${ARCH}} -pipe -isysroot ${SDKROOT} -O3 -DNDEBUG"
+  CFLAGS+=" -miphoneos-version-min=${IOS_MIN_VERSION} ${EXTRA_CFLAGS}"
 
-  if [[ -z "${XCODE}" ]]; then
-    echo "XCODE not available"
-    exit 1
-  elif [[ ${SDK} < 5.0.0 ]]; then
-    DEVROOT="${PLATFORMSROOT}/${PLATFORM}.platform/Developer/"
-  else
-    DEVROOT="${DEVELOPER}/Toolchains/XcodeDefault.xctoolchain"
-    CFLAGS+=" -miphoneos-version-min=5.0"
-    LDFLAGS+=" -miphoneos-version-min=5.0"
-  fi
-
-  export CFLAGS
-  export LDFLAGS
-  export CXXFLAGS=${CFLAGS}
+  set -x
   export PATH="${DEVROOT}/usr/bin:${OLDPATH}"
-
   ${SRCDIR}/configure --host=${ARCH}-apple-darwin --prefix=${ROOTDIR} \
     --build=$(${SRCDIR}/config.guess) \
     --disable-shared --enable-static \
-    --enable-libwebpdecoder --enable-swap-16bit-csp
+    --enable-libwebpdecoder --enable-swap-16bit-csp \
+    --enable-libwebpmux \
+    CFLAGS="${CFLAGS}"
+  set +x
 
-  # run make only in the src/ directory to create libwebpdecoder.a
-  cd src/
-  make V=0
-  make install
+  # Build only the libraries, skip the examples.
+  make V=0 -C sharpyuv
+  make V=0 -C src install
 
-  LIBLIST+=" ${ROOTDIR}/lib/libwebpdecoder.a"
+  LIBLIST+=" ${ROOTDIR}/lib/libwebp.a"
+  DECLIBLIST+=" ${ROOTDIR}/lib/libwebpdecoder.a"
+  MUXLIBLIST+=" ${ROOTDIR}/lib/libwebpmux.a"
+  DEMUXLIBLIST+=" ${ROOTDIR}/lib/libwebpdemux.a"
 
   make clean
-  cd ..
 
   export PATH=${OLDPATH}
 done
 
-cp -a ${SRCDIR}/src/webp/* ${TARGETDIR}/Headers/
+echo "LIBLIST = ${LIBLIST}"
+cp -a ${SRCDIR}/src/webp/{decode,encode,types}.h ${TARGETDIR}/Headers/
 ${LIPO} -create ${LIBLIST} -output ${TARGETDIR}/WebP
+
+echo "DECLIBLIST = ${DECLIBLIST}"
+cp -a ${SRCDIR}/src/webp/{decode,types}.h ${DECTARGETDIR}/Headers/
+${LIPO} -create ${DECLIBLIST} -output ${DECTARGETDIR}/WebPDecoder
+
+echo "MUXLIBLIST = ${MUXLIBLIST}"
+cp -a ${SRCDIR}/src/webp/{types,mux,mux_types}.h \
+    ${MUXTARGETDIR}/Headers/
+${LIPO} -create ${MUXLIBLIST} -output ${MUXTARGETDIR}/WebPMux
+
+echo "DEMUXLIBLIST = ${DEMUXLIBLIST}"
+cp -a ${SRCDIR}/src/webp/{decode,types,mux_types,demux}.h \
+    ${DEMUXTARGETDIR}/Headers/
+${LIPO} -create ${DEMUXLIBLIST} -output ${DEMUXTARGETDIR}/WebPDemux
+
+echo  "SUCCESS"

m4/ax_pthread.m4

@@ -82,7 +82,7 @@
 #   modified version of the Autoconf Macro, you may extend this special
 #   exception to the GPL to apply to your modified version as well.
 
-#serial 18
+#serial 21
 
 AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD])
 AC_DEFUN([AX_PTHREAD], [
@@ -103,8 +103,8 @@ if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then
         save_LIBS="$LIBS"
         LIBS="$PTHREAD_LIBS $LIBS"
         AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS])
-        AC_TRY_LINK_FUNC(pthread_join, ax_pthread_ok=yes)
-        AC_MSG_RESULT($ax_pthread_ok)
+        AC_TRY_LINK_FUNC([pthread_join], [ax_pthread_ok=yes])
+        AC_MSG_RESULT([$ax_pthread_ok])
         if test x"$ax_pthread_ok" = xno; then
                 PTHREAD_LIBS=""
                 PTHREAD_CFLAGS=""
@@ -164,6 +164,20 @@ case ${host_os} in
         ;;
 esac
 
+# Clang doesn't consider unrecognized options an error unless we specify
+# -Werror. We throw in some extra Clang-specific options to ensure that
+# this doesn't happen for GCC, which also accepts -Werror.
+
+AC_MSG_CHECKING([if compiler needs -Werror to reject unknown flags])
+save_CFLAGS="$CFLAGS"
+ax_pthread_extra_flags="-Werror"
+CFLAGS="$CFLAGS $ax_pthread_extra_flags -Wunknown-warning-option -Wsizeof-array-argument"
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([int foo(void);],[foo()])],
+                  [AC_MSG_RESULT([yes])],
+                  [ax_pthread_extra_flags=
+                   AC_MSG_RESULT([no])])
+CFLAGS="$save_CFLAGS"
+
 if test x"$ax_pthread_ok" = xno; then
 for flag in $ax_pthread_flags; do
 
@@ -178,7 +192,7 @@ for flag in $ax_pthread_flags; do
                 ;;
 
                 pthread-config)
-                AC_CHECK_PROG(ax_pthread_config, pthread-config, yes, no)
+                AC_CHECK_PROG([ax_pthread_config], [pthread-config], [yes], [no])
                 if test x"$ax_pthread_config" = xno; then continue; fi
                 PTHREAD_CFLAGS="`pthread-config --cflags`"
                 PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`"
@@ -193,7 +207,7 @@ for flag in $ax_pthread_flags; do
         save_LIBS="$LIBS"
         save_CFLAGS="$CFLAGS"
         LIBS="$PTHREAD_LIBS $LIBS"
-        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
+        CFLAGS="$CFLAGS $PTHREAD_CFLAGS $ax_pthread_extra_flags"
 
         # Check for various functions.  We must include pthread.h,
         # since some functions may be macros.  (On the Sequent, we
@@ -219,7 +233,7 @@ for flag in $ax_pthread_flags; do
         LIBS="$save_LIBS"
         CFLAGS="$save_CFLAGS"
 
-        AC_MSG_RESULT($ax_pthread_ok)
+        AC_MSG_RESULT([$ax_pthread_ok])
         if test "x$ax_pthread_ok" = xyes; then
                 break;
         fi
@@ -245,9 +259,9 @@ if test "x$ax_pthread_ok" = xyes; then
                 [attr_name=$attr; break],
                 [])
         done
-        AC_MSG_RESULT($attr_name)
+        AC_MSG_RESULT([$attr_name])
         if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then
-            AC_DEFINE_UNQUOTED(PTHREAD_CREATE_JOINABLE, $attr_name,
+            AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE], [$attr_name],
                                [Define to necessary symbol if this constant
                                 uses a non-standard name on your system.])
         fi
@@ -261,45 +275,54 @@ if test "x$ax_pthread_ok" = xyes; then
             if test "$GCC" = "yes"; then
                 flag="-D_REENTRANT"
             else
+                # TODO: What about Clang on Solaris?
                 flag="-mt -D_REENTRANT"
             fi
             ;;
         esac
-        AC_MSG_RESULT(${flag})
+        AC_MSG_RESULT([$flag])
         if test "x$flag" != xno; then
             PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS"
         fi
 
         AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT],
-            ax_cv_PTHREAD_PRIO_INHERIT, [
-                AC_LINK_IFELSE([
-                    AC_LANG_PROGRAM([[#include <pthread.h>]], [[int i = PTHREAD_PRIO_INHERIT;]])],
+            [ax_cv_PTHREAD_PRIO_INHERIT], [
+                AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
+                                                [[int i = PTHREAD_PRIO_INHERIT;]])],
                     [ax_cv_PTHREAD_PRIO_INHERIT=yes],
                     [ax_cv_PTHREAD_PRIO_INHERIT=no])
             ])
         AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes"],
-            AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], 1, [Have PTHREAD_PRIO_INHERIT.]))
+            [AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have PTHREAD_PRIO_INHERIT.])])
 
         LIBS="$save_LIBS"
         CFLAGS="$save_CFLAGS"
 
-        # More AIX lossage: must compile with xlc_r or cc_r
-        if test x"$GCC" != xyes; then
-          AC_CHECK_PROGS(PTHREAD_CC, xlc_r cc_r, ${CC})
-        else
-          PTHREAD_CC=$CC
+        # More AIX lossage: compile with *_r variant
+        if test "x$GCC" != xyes; then
+            case $host_os in
+                aix*)
+                AS_CASE(["x/$CC"],
+                  [x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6],
+                  [#handle absolute path differently from PATH based program lookup
+                   AS_CASE(["x$CC"],
+                     [x/*],
+                     [AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"])],
+                     [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])])
+                ;;
+            esac
         fi
-else
-        PTHREAD_CC="$CC"
 fi
 
-AC_SUBST(PTHREAD_LIBS)
-AC_SUBST(PTHREAD_CFLAGS)
-AC_SUBST(PTHREAD_CC)
+test -n "$PTHREAD_CC" || PTHREAD_CC="$CC"
+
+AC_SUBST([PTHREAD_LIBS])
+AC_SUBST([PTHREAD_CFLAGS])
+AC_SUBST([PTHREAD_CC])
 
 # Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
 if test x"$ax_pthread_ok" = xyes; then
-        ifelse([$1],,AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.]),[$1])
+        ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])
         :
 else
         ax_pthread_ok=no

makefile.unix

@@ -2,8 +2,8 @@
 # system, for simple local building of the libraries and tools.
 # It will not install the libraries system-wide, but just create the 'cwebp'
 # and 'dwebp' tools in the examples/ directory, along with the static
-# libraries 'src/libwebp.a', 'src/libwebpdecoder.a', 'src/mux/libwebpmux.a' and
-# 'src/demux/libwebpdemux.a'.
+# libraries 'src/libwebp.a', 'src/libwebpdecoder.a', 'src/mux/libwebpmux.a',
+# 'src/demux/libwebpdemux.a' and 'extras/libwebpextras.a'.
 #
 # To build the library and examples, use:
 #    make -f makefile.unix
@@ -25,16 +25,29 @@ ifeq ($(strip $(shell uname)), Darwin)
   # Failure observed with: gcc 4.2.1 and 4.0.1.
   EXTRA_FLAGS += -fno-common
   EXTRA_FLAGS += -DHAVE_GLUT_GLUT_H
+  EXTRA_FLAGS += -Wno-deprecated-declarations
   EXTRA_FLAGS += -I/opt/local/include
   EXTRA_LIBS  += -L/opt/local/lib
   GL_LIBS = -framework GLUT -framework OpenGL
 else
+  EXTRA_FLAGS += -I/usr/local/include
+  EXTRA_LIBS  += -L/usr/local/lib
   GL_LIBS = -lglut -lGL
 endif
 
+# SDL flags: use sdl-config if it exists
+SDL_CONFIG = $(shell sdl-config --version 2> /dev/null)
+ifneq ($(SDL_CONFIG),)
+  SDL_LIBS = $(shell sdl-config --libs)
+  SDL_FLAGS = $(shell sdl-config --cflags)
+else
+  # use best-guess
+  SDL_LIBS = -lSDL
+  SDL_FLAGS =
+endif
 
 # To install libraries on Mac OS X:
-# 1. Install MacPorts (http://www.macports.org/install.php)
+# 1. Install MacPorts (https://www.macports.org/install.php)
 # 2. Run "sudo port install jpeg"
 # 3. Run "sudo port install libpng"
 # 4. Run "sudo port install tiff"
@@ -51,126 +64,237 @@ endif
 # 'make -f makefile.unix EXTRA_FLAGS=-m32' to that effect.
 # EXTRA_FLAGS += -m32
 
-# Extra flags to enable experimental features and code
-# EXTRA_FLAGS += -DWEBP_EXPERIMENTAL_FEATURES
-
 # Extra flags to enable byte swap for 16 bit colorspaces.
-# EXTRA_FLAGS += -DWEBP_SWAP_16BIT_CSP
+# EXTRA_FLAGS += -DWEBP_SWAP_16BIT_CSP=1
 
 # Extra flags to enable multi-threading
 EXTRA_FLAGS += -DWEBP_USE_THREAD
 EXTRA_LIBS += -lpthread
 
+# Control symbol visibility. Comment out if your compiler doesn't support it.
+EXTRA_FLAGS += -fvisibility=hidden
+
 # Extra flags to emulate C89 strictness with the full ANSI
 EXTRA_FLAGS += -Wextra -Wold-style-definition
 EXTRA_FLAGS += -Wmissing-prototypes
 EXTRA_FLAGS += -Wmissing-declarations
 EXTRA_FLAGS += -Wdeclaration-after-statement
 EXTRA_FLAGS += -Wshadow
+EXTRA_FLAGS += -Wformat-security -Wformat-nonliteral
 # EXTRA_FLAGS += -Wvla
 
+# SSE4.1-specific flags:
+ifeq ($(HAVE_SSE41), 1)
+EXTRA_FLAGS += -DWEBP_HAVE_SSE41
+src/dsp/%_sse41.o: EXTRA_FLAGS += -msse4.1
+endif
+
+# NEON-specific flags:
+# EXTRA_FLAGS += -march=armv7-a -mfloat-abi=hard -mfpu=neon -mtune=cortex-a8
+# -> seems to make the overall lib slower: -fno-split-wide-types
+
+# MIPS (MSA) 32-bit build specific flags for mips32r5 (p5600):
+# EXTRA_FLAGS += -mips32r5 -mabi=32 -mtune=p5600 -mmsa -mfp64
+# EXTRA_FLAGS += -msched-weight -mload-store-pairs
+
+# MIPS (MSA) 64-bit build specific flags for mips64r6 (i6400):
+# EXTRA_FLAGS += -mips64r6 -mabi=64 -mtune=i6400 -mmsa -mfp64
+# EXTRA_FLAGS += -msched-weight -mload-store-pairs
+
 #### Nothing should normally be changed below this line ####
 
 AR = ar
 ARFLAGS = r
+CPPFLAGS = -I. -Isrc/ -Wall
+ifeq ($(DEBUG), 1)
+  CFLAGS = -g
+else
+  CFLAGS = -O3 -DNDEBUG
+endif
+CFLAGS += $(EXTRA_FLAGS)
 CC = gcc
-CPPFLAGS = -Isrc/ -Wall
-CFLAGS = -O3 -DNDEBUG $(EXTRA_FLAGS)
 INSTALL = install
 GROFF = /usr/bin/groff
 COL = /usr/bin/col
 LDFLAGS = $(EXTRA_LIBS) $(EXTRA_FLAGS) -lm
 
+ifdef BITTRACE
+CFLAGS += -DBITTRACE=$(BITTRACE)
+endif
+
+ANIM_UTIL_OBJS = \
+    examples/anim_util.o \
+
+SHARPYUV_OBJS = \
+    sharpyuv/sharpyuv.o \
+    sharpyuv/sharpyuv_csp.o \
+    sharpyuv/sharpyuv_dsp.o \
+    sharpyuv/sharpyuv_gamma.o \
+    sharpyuv/sharpyuv_neon.o \
+    sharpyuv/sharpyuv_sse2.o \
+
 DEC_OBJS = \
-    src/dec/alpha.o \
-    src/dec/buffer.o \
-    src/dec/frame.o \
-    src/dec/idec.o \
-    src/dec/io.o \
-    src/dec/layer.o \
-    src/dec/quant.o \
-    src/dec/tree.o \
-    src/dec/vp8.o \
-    src/dec/vp8l.o \
-    src/dec/webp.o \
+    src/dec/alpha_dec.o \
+    src/dec/buffer_dec.o \
+    src/dec/frame_dec.o \
+    src/dec/idec_dec.o \
+    src/dec/io_dec.o \
+    src/dec/quant_dec.o \
+    src/dec/tree_dec.o \
+    src/dec/vp8_dec.o \
+    src/dec/vp8l_dec.o \
+    src/dec/webp_dec.o \
 
 DEMUX_OBJS = \
+    src/demux/anim_decode.o \
     src/demux/demux.o \
 
 DSP_DEC_OBJS = \
+    src/dsp/alpha_processing.o \
+    src/dsp/alpha_processing_mips_dsp_r2.o \
+    src/dsp/alpha_processing_neon.o \
+    src/dsp/alpha_processing_sse2.o \
+    src/dsp/alpha_processing_sse41.o \
     src/dsp/cpu.o \
     src/dsp/dec.o \
+    src/dsp/dec_clip_tables.o \
+    src/dsp/dec_mips32.o \
+    src/dsp/dec_mips_dsp_r2.o \
+    src/dsp/dec_msa.o \
     src/dsp/dec_neon.o \
     src/dsp/dec_sse2.o \
+    src/dsp/dec_sse41.o \
+    src/dsp/filters.o \
+    src/dsp/filters_mips_dsp_r2.o \
+    src/dsp/filters_msa.o \
+    src/dsp/filters_neon.o \
+    src/dsp/filters_sse2.o \
     src/dsp/lossless.o \
+    src/dsp/lossless_mips_dsp_r2.o \
+    src/dsp/lossless_msa.o \
+    src/dsp/lossless_neon.o \
+    src/dsp/lossless_sse2.o \
+    src/dsp/lossless_sse41.o \
+    src/dsp/rescaler.o \
+    src/dsp/rescaler_mips32.o \
+    src/dsp/rescaler_mips_dsp_r2.o \
+    src/dsp/rescaler_msa.o \
+    src/dsp/rescaler_neon.o \
+    src/dsp/rescaler_sse2.o \
     src/dsp/upsampling.o \
+    src/dsp/upsampling_mips_dsp_r2.o \
+    src/dsp/upsampling_msa.o \
     src/dsp/upsampling_neon.o \
     src/dsp/upsampling_sse2.o \
+    src/dsp/upsampling_sse41.o \
     src/dsp/yuv.o \
+    src/dsp/yuv_mips32.o \
+    src/dsp/yuv_mips_dsp_r2.o \
+    src/dsp/yuv_neon.o \
+    src/dsp/yuv_sse2.o \
+    src/dsp/yuv_sse41.o \
 
 DSP_ENC_OBJS = \
+    src/dsp/cost.o \
+    src/dsp/cost_mips32.o \
+    src/dsp/cost_mips_dsp_r2.o \
+    src/dsp/cost_neon.o \
+    src/dsp/cost_sse2.o \
     src/dsp/enc.o \
+    src/dsp/enc_mips32.o \
+    src/dsp/enc_mips_dsp_r2.o \
+    src/dsp/enc_msa.o \
     src/dsp/enc_neon.o \
     src/dsp/enc_sse2.o \
+    src/dsp/enc_sse41.o \
+    src/dsp/lossless_enc.o \
+    src/dsp/lossless_enc_mips32.o \
+    src/dsp/lossless_enc_mips_dsp_r2.o \
+    src/dsp/lossless_enc_msa.o \
+    src/dsp/lossless_enc_neon.o \
+    src/dsp/lossless_enc_sse2.o \
+    src/dsp/lossless_enc_sse41.o \
+    src/dsp/ssim.o \
+    src/dsp/ssim_sse2.o \
 
 ENC_OBJS = \
-    src/enc/alpha.o \
-    src/enc/analysis.o \
-    src/enc/backward_references.o \
-    src/enc/config.o \
-    src/enc/cost.o \
-    src/enc/filter.o \
-    src/enc/frame.o \
-    src/enc/histogram.o \
-    src/enc/iterator.o \
-    src/enc/layer.o \
-    src/enc/picture.o \
-    src/enc/quant.o \
-    src/enc/syntax.o \
-    src/enc/token.o \
-    src/enc/tree.o \
-    src/enc/vp8l.o \
-    src/enc/webpenc.o \
+    src/enc/alpha_enc.o \
+    src/enc/analysis_enc.o \
+    src/enc/backward_references_cost_enc.o \
+    src/enc/backward_references_enc.o \
+    src/enc/config_enc.o \
+    src/enc/cost_enc.o \
+    src/enc/filter_enc.o \
+    src/enc/frame_enc.o \
+    src/enc/histogram_enc.o \
+    src/enc/iterator_enc.o \
+    src/enc/near_lossless_enc.o \
+    src/enc/picture_enc.o \
+    src/enc/picture_csp_enc.o \
+    src/enc/picture_psnr_enc.o \
+    src/enc/picture_rescale_enc.o \
+    src/enc/picture_tools_enc.o \
+    src/enc/predictor_enc.o \
+    src/enc/quant_enc.o \
+    src/enc/syntax_enc.o \
+    src/enc/token_enc.o \
+    src/enc/tree_enc.o \
+    src/enc/vp8l_enc.o \
+    src/enc/webp_enc.o \
 
 EX_FORMAT_DEC_OBJS = \
-    examples/jpegdec.o \
-    examples/metadata.o \
-    examples/pngdec.o \
-    examples/tiffdec.o \
+    imageio/image_dec.o \
+    imageio/jpegdec.o \
+    imageio/metadata.o \
+    imageio/pngdec.o \
+    imageio/pnmdec.o \
+    imageio/tiffdec.o \
+    imageio/webpdec.o \
+
+EX_FORMAT_ENC_OBJS = \
+    imageio/image_enc.o \
 
 EX_UTIL_OBJS = \
     examples/example_util.o \
 
-GIF2WEBP_UTIL_OBJS = \
-    examples/gif2webp_util.o \
+GIFDEC_OBJS = \
+    examples/gifdec.o \
+
+IMAGE_UTIL_OBJS = \
+    imageio/imageio_util.o \
 
 MUX_OBJS = \
+    src/mux/anim_encode.o \
     src/mux/muxedit.o \
     src/mux/muxinternal.o \
     src/mux/muxread.o \
 
 UTILS_DEC_OBJS = \
-    src/utils/alpha_processing.o \
-    src/utils/bit_reader.o \
-    src/utils/color_cache.o \
-    src/utils/filters.o \
-    src/utils/huffman.o \
-    src/utils/quant_levels_dec.o \
-    src/utils/random.o \
-    src/utils/rescaler.o \
-    src/utils/thread.o \
+    src/utils/bit_reader_utils.o \
+    src/utils/color_cache_utils.o \
+    src/utils/filters_utils.o \
+    src/utils/huffman_utils.o \
+    src/utils/quant_levels_dec_utils.o \
+    src/utils/random_utils.o \
+    src/utils/rescaler_utils.o \
+    src/utils/thread_utils.o \
     src/utils/utils.o \
 
 UTILS_ENC_OBJS = \
-    src/utils/bit_writer.o \
-    src/utils/huffman_encode.o \
-    src/utils/quant_levels.o \
+    src/utils/bit_writer_utils.o \
+    src/utils/huffman_encode_utils.o \
+    src/utils/quant_levels_utils.o \
+
+EXTRA_OBJS = \
+    extras/extras.o \
+    extras/quality_estimate.o \
 
 LIBWEBPDECODER_OBJS = $(DEC_OBJS) $(DSP_DEC_OBJS) $(UTILS_DEC_OBJS)
-LIBWEBP_OBJS = $(LIBWEBPDECODER_OBJS) $(ENC_OBJS) $(DSP_ENC_OBJS) \
-               $(UTILS_ENC_OBJS)
+LIBWEBP_OBJS = $(SHARPYUV_OBJS) $(LIBWEBPDECODER_OBJS) $(ENC_OBJS) \
+               $(DSP_ENC_OBJS) $(UTILS_ENC_OBJS)
 LIBWEBPMUX_OBJS = $(MUX_OBJS)
 LIBWEBPDEMUX_OBJS = $(DEMUX_OBJS)
+LIBWEBPEXTRA_OBJS = $(EXTRA_OBJS)
 
 HDRS_INSTALLED = \
     src/webp/decode.h \
@@ -181,52 +305,92 @@ HDRS_INSTALLED = \
     src/webp/types.h \
 
 HDRS = \
-    src/dec/alphai.h \
-    src/dec/decode_vp8.h \
-    src/dec/vp8i.h \
-    src/dec/vp8li.h \
-    src/dec/webpi.h \
+    src/dec/alphai_dec.h \
+    src/dec/common_dec.h \
+    src/dec/vp8_dec.h \
+    src/dec/vp8i_dec.h \
+    src/dec/vp8li_dec.h \
+    src/dec/webpi_dec.h \
+    src/dsp/common_sse2.h \
+    src/dsp/cpu.h \
     src/dsp/dsp.h \
     src/dsp/lossless.h \
+    src/dsp/lossless_common.h \
+    src/dsp/mips_macro.h \
+    src/dsp/msa_macro.h \
+    src/dsp/neon.h \
     src/dsp/yuv.h \
-    src/enc/cost.h \
-    src/enc/vp8enci.h \
-    src/utils/alpha_processing.h \
-    src/utils/bit_reader.h \
-    src/utils/bit_writer.h \
-    src/utils/color_cache.h \
-    src/utils/filters.h \
-    src/utils/huffman.h \
-    src/utils/huffman_encode.h \
-    src/utils/quant_levels.h \
-    src/utils/quant_levels_dec.h \
-    src/utils/random.h \
-    src/utils/rescaler.h \
-    src/utils/thread.h \
+    src/enc/backward_references_enc.h \
+    src/enc/cost_enc.h \
+    src/enc/histogram_enc.h \
+    src/enc/vp8i_enc.h \
+    src/enc/vp8li_enc.h \
+    src/mux/animi.h \
+    src/mux/muxi.h \
+    src/utils/bit_reader_utils.h \
+    src/utils/bit_reader_inl_utils.h \
+    src/utils/bit_writer_utils.h \
+    src/utils/color_cache_utils.h \
+    src/utils/endian_inl_utils.h \
+    src/utils/filters_utils.h \
+    src/utils/huffman_utils.h \
+    src/utils/huffman_encode_utils.h \
+    src/utils/quant_levels_utils.h \
+    src/utils/quant_levels_dec_utils.h \
+    src/utils/random_utils.h \
+    src/utils/rescaler_utils.h \
+    src/utils/thread_utils.h \
+    src/utils/utils.h \
     src/webp/format_constants.h \
     $(HDRS_INSTALLED) \
 
-OUT_LIBS = examples/libexample_util.a src/libwebpdecoder.a src/libwebp.a
+OUT_LIBS = examples/libexample_util.a
+OUT_LIBS += imageio/libimageio_util.a
+OUT_LIBS += imageio/libimagedec.a
+OUT_LIBS += imageio/libimageenc.a
+OUT_LIBS += src/libwebpdecoder.a
+OUT_LIBS += src/libwebp.a
+EXTRA_LIB = extras/libwebpextras.a
 OUT_EXAMPLES = examples/cwebp examples/dwebp
-EXTRA_EXAMPLES = examples/gif2webp examples/vwebp examples/webpmux
+EXTRA_EXAMPLES = examples/gif2webp examples/vwebp examples/webpmux \
+                 examples/anim_diff examples/anim_dump \
+                 examples/img2webp examples/webpinfo
+OTHER_EXAMPLES = extras/get_disto extras/webp_quality extras/vwebp_sdl
 
 OUTPUT = $(OUT_LIBS) $(OUT_EXAMPLES)
 ifeq ($(MAKECMDGOALS),clean)
-  OUTPUT += $(EXTRA_EXAMPLES)
-  OUTPUT += src/demux/libwebpdemux.a src/mux/libwebpmux.a
-  OUTPUT += examples/libgif2webp_util.a
+  OUTPUT += $(EXTRA_EXAMPLES) $(OTHER_EXAMPLES)
+  OUTPUT += src/demux/libwebpdemux.a src/mux/libwebpmux.a $(EXTRA_LIB)
+  OUTPUT += examples/libgifdec.a examples/libanim_util.a
 endif
 
 ex: $(OUT_EXAMPLES)
-all: ex $(EXTRA_EXAMPLES)
+all: ex $(EXTRA_EXAMPLES) $(OTHER_EXAMPLES)
+extras: $(EXTRA_LIB)
 
 $(EX_FORMAT_DEC_OBJS): %.o: %.h
 
-%.o: %.c $(HDRS)
-	$(CC) $(CFLAGS) $(CPPFLAGS) -c $< -o $@
+# special dependencies:
+#   tree_dec.c/vp8_dec.c/bit_reader_utils.c <->
+#     bit_reader_inl_utils.h, endian_inl_utils.h
+#   bit_writer_utils.c <-> endian_inl_utils.h
+src/dec/tree_dec.o: src/utils/bit_reader_inl_utils.h
+src/dec/tree_dec.o: src/utils/endian_inl_utils.h
+src/dec/vp8_dec.o: src/utils/bit_reader_inl_utils.h src/utils/endian_inl_utils.h
+src/utils/bit_reader_utils.o: src/utils/bit_reader_inl_utils.h
+src/utils/bit_reader_utils.o: src/utils/endian_inl_utils.h
+src/utils/bit_writer_utils.o: src/utils/endian_inl_utils.h
 
+%.o: %.c $(HDRS)
+	$(CC) $(CPPFLAGS) $(CFLAGS) -c $< -o $@
+
+examples/libanim_util.a: $(ANIM_UTIL_OBJS)
 examples/libexample_util.a: $(EX_UTIL_OBJS)
-examples/libgif2webp_util.a: $(GIF2WEBP_UTIL_OBJS)
+examples/libgifdec.a: $(GIFDEC_OBJS)
+extras/libwebpextras.a: $(LIBWEBPEXTRA_OBJS)
+imageio/libimagedec.a: $(EX_FORMAT_DEC_OBJS)
+imageio/libimageenc.a: $(EX_FORMAT_ENC_OBJS)
+imageio/libimageio_util.a: $(IMAGE_UTIL_OBJS)
 src/libwebpdecoder.a: $(LIBWEBPDECODER_OBJS)
 src/libwebp.a: $(LIBWEBP_OBJS)
 src/mux/libwebpmux.a: $(LIBWEBPMUX_OBJS)
@@ -235,28 +399,78 @@ src/demux/libwebpdemux.a: $(LIBWEBPDEMUX_OBJS)
 %.a:
 	$(AR) $(ARFLAGS) $@ $^
 
-examples/cwebp: examples/cwebp.o $(EX_FORMAT_DEC_OBJS)
+examples/anim_diff: examples/anim_diff.o $(ANIM_UTIL_OBJS) $(GIFDEC_OBJS)
+examples/anim_dump: examples/anim_dump.o $(ANIM_UTIL_OBJS) $(GIFDEC_OBJS)
+examples/cwebp: examples/cwebp.o
 examples/dwebp: examples/dwebp.o
-examples/gif2webp: examples/gif2webp.o
+examples/gif2webp: examples/gif2webp.o $(GIFDEC_OBJS)
 examples/vwebp: examples/vwebp.o
 examples/webpmux: examples/webpmux.o
+examples/img2webp: examples/img2webp.o
+examples/webpinfo: examples/webpinfo.o
 
+examples/anim_diff: examples/libanim_util.a examples/libgifdec.a
+examples/anim_diff: src/demux/libwebpdemux.a examples/libexample_util.a
+examples/anim_diff: imageio/libimageio_util.a src/libwebp.a
+examples/anim_diff: override EXTRA_LIBS += $(GIF_LIBS)
+examples/anim_diff: EXTRA_FLAGS += -DWEBP_HAVE_GIF
+examples/anim_dump: examples/libanim_util.a examples/libgifdec.a
+examples/anim_dump: src/demux/libwebpdemux.a
+examples/anim_dump: examples/libexample_util.a
+examples/anim_dump: imageio/libimageio_util.a
+examples/anim_dump: imageio/libimageenc.a
+examples/anim_dump: src/libwebp.a
+examples/anim_dump: override EXTRA_LIBS += $(GIF_LIBS) $(DWEBP_LIBS)
+examples/cwebp: examples/libexample_util.a
+examples/cwebp: imageio/libimagedec.a
+examples/cwebp: src/demux/libwebpdemux.a
+examples/cwebp: imageio/libimageio_util.a
 examples/cwebp: src/libwebp.a
-examples/cwebp: EXTRA_LIBS += $(CWEBP_LIBS)
-examples/dwebp: examples/libexample_util.a src/libwebpdecoder.a
-examples/dwebp: EXTRA_LIBS += $(DWEBP_LIBS)
-examples/gif2webp: examples/libexample_util.a examples/libgif2webp_util.a
-examples/gif2webp: src/mux/libwebpmux.a src/libwebp.a
-examples/gif2webp: EXTRA_LIBS += $(GIF_LIBS)
+examples/cwebp: override EXTRA_LIBS += $(CWEBP_LIBS)
+examples/dwebp: examples/libexample_util.a
+examples/dwebp: imageio/libimagedec.a
+examples/dwebp: src/demux/libwebpdemux.a
+examples/dwebp: imageio/libimageenc.a
+examples/dwebp: imageio/libimageio_util.a
+examples/dwebp: src/libwebp.a
+examples/dwebp: override EXTRA_LIBS += $(DWEBP_LIBS)
+examples/gif2webp: examples/libexample_util.a imageio/libimageio_util.a
+examples/gif2webp: examples/libgifdec.a src/mux/libwebpmux.a src/libwebp.a
+examples/gif2webp: override EXTRA_LIBS += $(GIF_LIBS)
 examples/gif2webp: EXTRA_FLAGS += -DWEBP_HAVE_GIF
 examples/vwebp: examples/libexample_util.a src/demux/libwebpdemux.a
-examples/vwebp: src/libwebp.a
-examples/vwebp: EXTRA_LIBS += $(GL_LIBS)
+examples/vwebp: imageio/libimageio_util.a src/libwebp.a
+examples/vwebp: override EXTRA_LIBS += $(GL_LIBS)
 examples/vwebp: EXTRA_FLAGS += -DWEBP_HAVE_GL
-examples/webpmux: examples/libexample_util.a src/mux/libwebpmux.a
-examples/webpmux: src/libwebpdecoder.a
+examples/webpmux: examples/libexample_util.a imageio/libimageio_util.a
+examples/webpmux: src/mux/libwebpmux.a src/libwebpdecoder.a
+examples/img2webp: examples/libexample_util.a imageio/libimageio_util.a
+examples/img2webp: imageio/libimagedec.a
+examples/img2webp: src/demux/libwebpdemux.a
+examples/img2webp: src/mux/libwebpmux.a src/libwebp.a
+examples/img2webp: override EXTRA_LIBS += $(CWEBP_LIBS)
+examples/webpinfo: examples/libexample_util.a imageio/libimageio_util.a
+examples/webpinfo: src/libwebpdecoder.a
 
-$(OUT_EXAMPLES) $(EXTRA_EXAMPLES):
+extras/get_disto: extras/get_disto.o
+extras/get_disto: imageio/libimagedec.a
+extras/get_disto: src/demux/libwebpdemux.a
+extras/get_disto: imageio/libimageio_util.a
+extras/get_disto: src/libwebp.a
+extras/get_disto: override EXTRA_LIBS += $(CWEBP_LIBS)
+
+extras/webp_quality: extras/webp_quality.o
+extras/webp_quality: imageio/libimageio_util.a
+extras/webp_quality: $(EXTRA_LIB) src/libwebp.a
+
+extras/vwebp_sdl: extras/vwebp_sdl.o
+extras/vwebp_sdl: extras/webp_to_sdl.o
+extras/vwebp_sdl: imageio/libimageio_util.a
+extras/vwebp_sdl: src/libwebp.a
+extras/vwebp_sdl: EXTRA_FLAGS += -DWEBP_HAVE_SDL $(SDL_FLAGS)
+extras/vwebp_sdl: override EXTRA_LIBS += $(SDL_LIBS)
+
+$(OUT_EXAMPLES) $(EXTRA_EXAMPLES) $(OTHER_EXAMPLES):
 	$(CC) -o $@ $^ $(LDFLAGS)
 
 dist: DESTDIR := dist
@@ -270,9 +484,10 @@ dist: all
 	$(INSTALL) -m644 src/demux/libwebpdemux.a $(DESTDIR)/lib
 	$(INSTALL) -m644 src/mux/libwebpmux.a $(DESTDIR)/lib
 	umask 022; \
-	for m in man/[cd]webp.1 man/gif2webp.1 man/webpmux.1; do \
+	for m in man/[cdv]webp.1 man/gif2webp.1 man/webpmux.1 \
+                 man/img2webp.1 man/webpinfo.1; do \
 	  basenam=$$(basename $$m .1); \
-	  $(GROFF) -t -e -man -T utf8 $$m \
+	  $(GROFF) -t -e -man -T ascii $$m \
 	    | $(COL) -bx >$(DESTDIR)/doc/$${basenam}.txt; \
 	  $(GROFF) -t -e -man -T html $$m \
 	    | $(COL) -bx >$(DESTDIR)/doc/$${basenam}.html; \
@@ -281,6 +496,9 @@ dist: all
 clean:
 	$(RM) $(OUTPUT) *~ \
               examples/*.o examples/*~ \
+              extras/*.o extras/*~ \
+              imageio/*.o imageio/*~ \
+              sharpyuv/*.o sharpyuv/*~ \
               src/dec/*.o src/dec/*~ \
               src/demux/*.o src/demux/*~ \
               src/dsp/*.o src/dsp/*~ \
@@ -289,19 +507,5 @@ clean:
               src/utils/*.o src/utils/*~ \
               src/webp/*~ man/*~ doc/*~ swig/*~ \
 
-superclean: clean
-	$(RM) -r .git *.log *.cache *~
-	$(RM) -r .deps */.deps */*/.deps
-	$(RM) -r .libs */.libs */*/.libs
-	$(RM) */*.lo */*/*.lo
-	$(RM) */*.la */*/*.la
-	$(RM) Makefile */Makefile */*/Makefile
-	$(RM) Makefile.in */Makefile.in */*/Makefile.in
-	$(RM) config.log autom4te.cache libtool config.h stamp-h1
-	$(RM) aclocal.m4 compile
-	$(RM) config.guess config.h.in config.sub config.status
-	$(RM) configure depcomp install-sh ltmain.sh missing src/libwebp.pc
-	$(RM) m4/*
-
-.PHONY: all clean dist ex superclean
+.PHONY: all clean dist ex
 .SUFFIXES:

man/Makefile.am

@@ -1,8 +1,17 @@
 man_MANS = cwebp.1 dwebp.1
-if WANT_MUX
+if BUILD_MUX
   man_MANS += webpmux.1
 endif
 if BUILD_GIF2WEBP
   man_MANS += gif2webp.1
 endif
+if BUILD_IMG2WEBP
+  man_MANS += img2webp.1
+endif
+if BUILD_VWEBP
+  man_MANS += vwebp.1
+endif
+if BUILD_WEBPINFO
+  man_MANS += webpinfo.1
+endif
 EXTRA_DIST = $(man_MANS)