Merge "lossless.h: fix function declaration mismatches" into main

Extend VP8EncIterator::i4_boundary_ by 3 bytes to avoid Intra4Preds_NEON
reading deeper into the struct (likely padding) when top is positioned
at offset 29. This data is memset with MSan to prevent a warning due to
its incorrect modeling of tbl instructions.

Prior to:
  169dfbf9 disable Intra4Preds_NEON
there was a mismatch in the preprocessor checks for enabling the
function in NEON and removing the C version; NEON used `BPS == 32` while
the C code was removed unconditionally when building for aarch64. This
patch also normalizes those checks to look for `BPS == 32` and `BPS !=
32` as appropriate.

Bug: b:366668849,webp:372109644
Change-Id: Ic9e6ad4b2d844cb446decd63aec0b2676a89c8d0

.cmake-format.py

@@ -0,0 +1,240 @@
+# ----------------------------------
+# Options affecting listfile parsing
+# ----------------------------------
+with section("parse"):
+
+  # Specify structure for custom cmake functions
+  additional_commands = { 'foo': { 'flags': ['BAR', 'BAZ'],
+             'kwargs': {'DEPENDS': '*', 'HEADERS': '*', 'SOURCES': '*'}}}
+
+  # Override configurations per-command where available
+  override_spec = {}
+
+  # Specify variable tags.
+  vartags = []
+
+  # Specify property tags.
+  proptags = []
+
+# -----------------------------
+# Options affecting formatting.
+# -----------------------------
+with section("format"):
+
+  # Disable formatting entirely, making cmake-format a no-op
+  disable = False
+
+  # How wide to allow formatted cmake files
+  line_width = 80
+
+  # How many spaces to tab for indent
+  tab_size = 2
+
+  # If true, lines are indented using tab characters (utf-8 0x09) instead of
+  # <tab_size> space characters (utf-8 0x20). In cases where the layout would
+  # require a fractional tab character, the behavior of the  fractional
+  # indentation is governed by <fractional_tab_policy>
+  use_tabchars = False
+
+  # If <use_tabchars> is True, then the value of this variable indicates how
+  # fractional indentions are handled during whitespace replacement. If set to
+  # 'use-space', fractional indentation is left as spaces (utf-8 0x20). If set
+  # to `round-up` fractional indentation is replaced with a single tab character
+  # (utf-8 0x09) effectively shifting the column to the next tabstop
+  fractional_tab_policy = 'use-space'
+
+  # If an argument group contains more than this many sub-groups (parg or kwarg
+  # groups) then force it to a vertical layout.
+  max_subgroups_hwrap = 3
+
+  # If a positional argument group contains more than this many arguments, then
+  # force it to a vertical layout.
+  max_pargs_hwrap = 6
+
+  # If a cmdline positional group consumes more than this many lines without
+  # nesting, then invalidate the layout (and nest)
+  max_rows_cmdline = 2
+
+  # If true, separate flow control names from their parentheses with a space
+  separate_ctrl_name_with_space = False
+
+  # If true, separate function names from parentheses with a space
+  separate_fn_name_with_space = False
+
+  # If a statement is wrapped to more than one line, than dangle the closing
+  # parenthesis on its own line.
+  dangle_parens = False
+
+  # If the trailing parenthesis must be 'dangled' on its on line, then align it
+  # to this reference: `prefix`: the start of the statement,  `prefix-indent`:
+  # the start of the statement, plus one indentation  level, `child`: align to
+  # the column of the arguments
+  dangle_align = 'prefix'
+
+  # If the statement spelling length (including space and parenthesis) is
+  # smaller than this amount, then force reject nested layouts.
+  min_prefix_chars = 4
+
+  # If the statement spelling length (including space and parenthesis) is larger
+  # than the tab width by more than this amount, then force reject un-nested
+  # layouts.
+  max_prefix_chars = 10
+
+  # If a candidate layout is wrapped horizontally but it exceeds this many
+  # lines, then reject the layout.
+  max_lines_hwrap = 2
+
+  # What style line endings to use in the output.
+  line_ending = 'unix'
+
+  # Format command names consistently as 'lower' or 'upper' case
+  command_case = 'canonical'
+
+  # Format keywords consistently as 'lower' or 'upper' case
+  keyword_case = 'unchanged'
+
+  # A list of command names which should always be wrapped
+  always_wrap = []
+
+  # If true, the argument lists which are known to be sortable will be sorted
+  # lexicographicall
+  enable_sort = True
+
+  # If true, the parsers may infer whether or not an argument list is sortable
+  # (without annotation).
+  autosort = False
+
+  # By default, if cmake-format cannot successfully fit everything into the
+  # desired linewidth it will apply the last, most agressive attempt that it
+  # made. If this flag is True, however, cmake-format will print error, exit
+  # with non-zero status code, and write-out nothing
+  require_valid_layout = False
+
+  # A dictionary mapping layout nodes to a list of wrap decisions. See the
+  # documentation for more information.
+  layout_passes = {}
+
+# ------------------------------------------------
+# Options affecting comment reflow and formatting.
+# ------------------------------------------------
+with section("markup"):
+
+  # What character to use for bulleted lists
+  bullet_char = '*'
+
+  # What character to use as punctuation after numerals in an enumerated list
+  enum_char = '.'
+
+  # If comment markup is enabled, don't reflow the first comment block in each
+  # listfile. Use this to preserve formatting of your copyright/license
+  # statements.
+  first_comment_is_literal = True
+
+  # If comment markup is enabled, don't reflow any comment block which matches
+  # this (regex) pattern. Default is `None` (disabled).
+  literal_comment_pattern = None
+
+  # Regular expression to match preformat fences in comments default=
+  # ``r'^\s*([`~]{3}[`~]*)(.*)$'``
+  fence_pattern = '^\\s*([`~]{3}[`~]*)(.*)$'
+
+  # Regular expression to match rulers in comments default=
+  # ``r'^\s*[^\w\s]{3}.*[^\w\s]{3}$'``
+  ruler_pattern = '^\\s*[^\\w\\s]{3}.*[^\\w\\s]{3}$'
+
+  # If a comment line matches starts with this pattern then it is explicitly a
+  # trailing comment for the preceeding argument. Default is '#<'
+  explicit_trailing_pattern = '#<'
+
+  # If a comment line starts with at least this many consecutive hash
+  # characters, then don't lstrip() them off. This allows for lazy hash rulers
+  # where the first hash char is not separated by space
+  hashruler_min_length = 10
+
+  # If true, then insert a space between the first hash char and remaining hash
+  # chars in a hash ruler, and normalize its length to fill the column
+  canonicalize_hashrulers = True
+
+  # enable comment markup parsing and reflow
+  enable_markup = True
+
+# ----------------------------
+# Options affecting the linter
+# ----------------------------
+with section("lint"):
+
+  # a list of lint codes to disable
+  disabled_codes = []
+
+  # regular expression pattern describing valid function names
+  function_pattern = '[0-9a-z_]+'
+
+  # regular expression pattern describing valid macro names
+  macro_pattern = '[0-9A-Z_]+'
+
+  # regular expression pattern describing valid names for variables with global
+  # (cache) scope
+  global_var_pattern = '[A-Z][0-9A-Z_]+'
+
+  # regular expression pattern describing valid names for variables with global
+  # scope (but internal semantic)
+  internal_var_pattern = '_[A-Z][0-9A-Z_]+'
+
+  # regular expression pattern describing valid names for variables with local
+  # scope
+  local_var_pattern = '[a-z][a-z0-9_]+'
+
+  # regular expression pattern describing valid names for privatedirectory
+  # variables
+  private_var_pattern = '_[0-9a-z_]+'
+
+  # regular expression pattern describing valid names for public directory
+  # variables
+  public_var_pattern = '[A-Z][0-9A-Z_]+'
+
+  # regular expression pattern describing valid names for function/macro
+  # arguments and loop variables.
+  argument_var_pattern = '[a-z][a-z0-9_]+'
+
+  # regular expression pattern describing valid names for keywords used in
+  # functions or macros
+  keyword_pattern = '[A-Z][0-9A-Z_]+'
+
+  # In the heuristic for C0201, how many conditionals to match within a loop in
+  # before considering the loop a parser.
+  max_conditionals_custom_parser = 2
+
+  # Require at least this many newlines between statements
+  min_statement_spacing = 1
+
+  # Require no more than this many newlines between statements
+  max_statement_spacing = 2
+  max_returns = 6
+  max_branches = 12
+  max_arguments = 5
+  max_localvars = 15
+  max_statements = 50
+
+# -------------------------------
+# Options affecting file encoding
+# -------------------------------
+with section("encode"):
+
+  # If true, emit the unicode byte-order mark (BOM) at the start of the file
+  emit_byteorder_mark = False
+
+  # Specify the encoding of the input file. Defaults to utf-8
+  input_encoding = 'utf-8'
+
+  # Specify the encoding of the output file. Defaults to utf-8. Note that cmake
+  # only claims to support utf-8 so be careful when using anything else
+  output_encoding = 'utf-8'
+
+# -------------------------------------
+# Miscellaneous configurations options.
+# -------------------------------------
+with section("misc"):
+
+  # A dictionary containing any per-command configuration overrides. Currently
+  # only `command_case` is supported.
+  per_command = {}

.gitattributes

@@ -1,5 +1,6 @@
 .gitattributes export-ignore
 .gitignore export-ignore
 .mailmap export-ignore
+*.bat text eol=crlf
 *.pdf -text -diff
 *.ppm -text -diff

.gitignore

@@ -1,8 +1,11 @@
 *.l[ao]
 *.[ao]
 *.pc
+.DS_Store
 .deps
+.idea
 .libs
+.vscode
 /aclocal.m4
 /ar-lib
 /autom4te.cache
@@ -20,9 +23,11 @@
 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
@@ -31,11 +36,22 @@ src/webp/stamp-h1
 *.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/huffman_fuzzer
+tests/fuzzer/mux_demux_api_fuzzer
+tests/fuzzer/simple_api_fuzzer

.mailmap

@@ -1,12 +1,19 @@
-<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>
+Yannis Guyon <yguyon@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 = yapf

AUTHORS

@@ -1,28 +1,52 @@
 Contributors:
+- Aidan O'Loan (aidanol at gmail dot com)
+- Alan Browning (browning at google dot com)
+- Alexandru Ardelean (ardeleanalex at gmail dot com)
+- Anuraag Agrawal (anuraaga at gmail dot com)
+- Arthur Eubanks (aeubanks at google 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)
+- H. Vetinari (h dot vetinari at gmx 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)
 - Jehan (jehan at girinstud dot io)
-- Johann (johann dot koenig at duck dot com)
+- Jeremy Maitin-Shepard (jbms at google dot com)
+- Johann Koenig (johann dot koenig at duck dot com)
+- Jonathan Grant (jgrantinfotech at gmail dot com)
+- Jonliu1993 (13720414433 at 163 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)
+- Masahiro Hanada (hanada at atmark-techno dot com)
 - Mikołaj Zalewski (mikolajz at google dot com)
 - Mislav Bradac (mislavm at google dot com)
+- natewood (natewood at fb dot com)
 - Nico Weber (thakis at chromium dot org)
 - Noel Chromium (noel at chromium dot org)
+- Nozomi Isozaki (nontan at pixiv dot co dot jp)
+- Oliver Wolff (oliver dot wolff at qt dot io)
 - Owen Rodley (orodley at google dot com)
+- Ozkan Sezer (sezeroz at gmail 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)
@@ -31,9 +55,13 @@ Contributors:
 - 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)
+- Thiago Perrotta (tperrotta at google 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

@@ -1,3 +1,5 @@
+# Ignore this file during non-NDK builds.
+ifdef NDK_ROOT
 LOCAL_PATH := $(call my-dir)
 
 WEBP_CFLAGS := -Wall -DANDROID -DHAVE_MALLOC_H -DHAVE_PTHREAD -DWEBP_USE_THREAD
@@ -33,6 +35,15 @@ else
   NEON := c
 endif
 
+sharpyuv_srcs := \
+    sharpyuv/sharpyuv.c \
+    sharpyuv/sharpyuv_cpu.c \
+    sharpyuv/sharpyuv_csp.c \
+    sharpyuv/sharpyuv_dsp.c \
+    sharpyuv/sharpyuv_gamma.c \
+    sharpyuv/sharpyuv_neon.$(NEON) \
+    sharpyuv/sharpyuv_sse2.c \
+
 dec_srcs := \
     src/dec/alpha_dec.c \
     src/dec/buffer_dec.c \
@@ -74,6 +85,7 @@ dsp_dec_srcs := \
     src/dsp/lossless_msa.c \
     src/dsp/lossless_neon.$(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 \
@@ -97,9 +109,9 @@ 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_avx2.c \
     src/dsp/enc_mips32.c \
     src/dsp/enc_mips_dsp_r2.c \
     src/dsp/enc_msa.c \
@@ -152,6 +164,7 @@ utils_dec_srcs := \
     src/utils/color_cache_utils.c \
     src/utils/filters_utils.c \
     src/utils/huffman_utils.c \
+    src/utils/palette.c \
     src/utils/quant_levels_dec_utils.c \
     src/utils/random_utils.c \
     src/utils/rescaler_utils.c \
@@ -174,7 +187,7 @@ LOCAL_SRC_FILES := \
     $(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
@@ -203,12 +216,13 @@ endif  # ENABLE_SHARED=1
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES := \
+    $(sharpyuv_srcs) \
     $(dsp_enc_srcs) \
     $(enc_srcs) \
     $(utils_enc_srcs) \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES += $(LOCAL_PATH)/src
+LOCAL_EXPORT_C_INCLUDES += $(LOCAL_PATH)/src $(LOCAL_PATH)
 
 # prefer arm over thumb mode for performance gains
 LOCAL_ARM_MODE := arm
@@ -231,7 +245,7 @@ include $(CLEAR_VARS)
 LOCAL_SRC_FILES := $(demux_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
@@ -254,7 +268,7 @@ include $(CLEAR_VARS)
 LOCAL_SRC_FILES := $(mux_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
@@ -278,3 +292,4 @@ include $(WEBP_SRC_PATH)/examples/Android.mk
 ifeq ($(USE_CPUFEATURES),yes)
   $(call import-module,android/cpufeatures)
 endif
+endif  # NDK_ROOT

CONTRIBUTING.md

@@ -0,0 +1,78 @@
+# 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.
+
+## Sending patches
+
+The basic git workflow for modifying libwebp code and sending for review is:
+
+1.  Get the latest version of the repository locally:
+
+    ```sh
+    git clone https://chromium.googlesource.com/webm/libwebp && cd libwebp
+    ```
+
+2.  Copy the commit-msg script into ./git/hooks (this will add an ID to all of
+    your commits):
+
+    ```sh
+    curl -Lo .git/hooks/commit-msg https://chromium-review.googlesource.com/tools/hooks/commit-msg && chmod u+x .git/hooks/commit-msg
+    ```
+
+3.  Modify the local copy of libwebp. Make sure the code
+    [builds successfully](https://chromium.googlesource.com/webm/libwebp/+/HEAD/doc/building.md#cmake).
+
+4.  Choose a short and representative commit message:
+
+    ```sh
+    git commit -a -m "Set commit message here"
+    ```
+
+5.  Send the patch for review:
+
+    ```sh
+    git push https://chromium-review.googlesource.com/webm/libwebp HEAD:refs/for/main
+    ```
+
+    Go to https://chromium-review.googlesource.com to view your patch and
+    request a review from the maintainers.
+
+See the
+[WebM Project page](https://www.webmproject.org/code/contribute/submitting-patches/)
+for additional details.
+
+## Code Style
+
+The C code style is based on the
+[Google C++ Style Guide](https://google.github.io/styleguide/cppguide.html) and
+`clang-format --style=Google`, though this project doesn't use the tool to
+enforce the formatting.
+
+CMake files are formatted with
+[cmake-format](https://cmake-format.readthedocs.io/en/latest/). `cmake-format
+-i` can be used to format individual files, it will use the settings from
+`.cmake-format.py`.
+
+## Community Guidelines
+
+This project follows
+[Google's Open Source Community Guidelines](https://opensource.google.com/conduct/).

Makefile.am

@@ -1,8 +1,8 @@
 ACLOCAL_AMFLAGS = -I m4
-SUBDIRS = src imageio man
+SUBDIRS = sharpyuv src imageio man
 EXTRA_DIST = COPYING autogen.sh
 
-if WANT_EXTRAS
+if BUILD_EXTRAS
   SUBDIRS += extras
 endif
 

Makefile.vc

@@ -5,12 +5,15 @@ LIBWEBPDECODER_BASENAME = libwebpdecoder
 LIBWEBP_BASENAME = libwebp
 LIBWEBPMUX_BASENAME = libwebpmux
 LIBWEBPDEMUX_BASENAME = libwebpdemux
+LIBSHARPYUV_BASENAME = libsharpyuv
 
 !IFNDEF ARCH
 !IF ! [ cl 2>&1 | find "x86" > NUL ]
 ARCH = x86
 !ELSE IF ! [ cl 2>&1 | find "x64" > NUL ]
 ARCH = x64
+!ELSE IF ! [ cl 2>&1 | find "ARM64" > NUL ]
+ARCH = ARM64
 !ELSE IF ! [ cl 2>&1 | find "ARM" > NUL ]
 ARCH = ARM
 !ELSE
@@ -28,15 +31,14 @@ PLATFORM_LDFLAGS = /SAFESEH
 
 NOLOGO     = /nologo
 CCNODBG    = cl.exe $(NOLOGO) /O2 /DNDEBUG
-CCDEBUG    = cl.exe $(NOLOGO) /Od /Gm /Zi /D_DEBUG /RTC1
+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
-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
 
@@ -53,11 +55,6 @@ OUTDIR = ..\obj\
 OUTDIR = $(OBJDIR)
 !ENDIF
 
-!IF "$(HAVE_AVX2)" == "1"
-CFLAGS = $(CFLAGS) /DWEBP_HAVE_AVX2
-AVX2_FLAGS = /arch:AVX2
-!ENDIF
-
 ##############################################################
 # Runtime library configuration
 !IF "$(RTLIBCFG)" == "static"
@@ -87,6 +84,7 @@ OUTPUT_DIRS = $(DIRBIN) $(DIRINC) $(DIRLIB) \
               $(DIROBJ)\extras \
               $(DIROBJ)\imageio \
               $(DIROBJ)\mux \
+              $(DIROBJ)\sharpyuv \
               $(DIROBJ)\utils \
 
 # Target configuration
@@ -101,6 +99,7 @@ LIBWEBPDECODER_BASENAME = $(LIBWEBPDECODER_BASENAME)_debug
 LIBWEBP_BASENAME = $(LIBWEBP_BASENAME)_debug
 LIBWEBPMUX_BASENAME = $(LIBWEBPMUX_BASENAME)_debug
 LIBWEBPDEMUX_BASENAME = $(LIBWEBPDEMUX_BASENAME)_debug
+LIBSHARPYUV_BASENAME = $(LIBSHARPYUV_BASENAME)_debug
 !ELSE IF "$(CFG)" == "release-dynamic"
 CC        = $(CCNODBG)
 RC        = $(RCNODBG)
@@ -114,6 +113,7 @@ LIBWEBPDECODER_BASENAME = $(LIBWEBPDECODER_BASENAME)_debug
 LIBWEBP_BASENAME = $(LIBWEBP_BASENAME)_debug
 LIBWEBPMUX_BASENAME = $(LIBWEBPMUX_BASENAME)_debug
 LIBWEBPDEMUX_BASENAME = $(LIBWEBPDEMUX_BASENAME)_debug
+LIBSHARPYUV_BASENAME = $(LIBSHARPYUV_BASENAME)_debug
 !ENDIF
 
 !IF "$(STATICLIBBUILD)" == "TRUE"
@@ -123,23 +123,28 @@ LIBWEBPDECODER = $(DIRLIB)\$(LIBWEBPDECODER_BASENAME).lib
 LIBWEBP = $(DIRLIB)\$(LIBWEBP_BASENAME).lib
 LIBWEBPMUX = $(DIRLIB)\$(LIBWEBPMUX_BASENAME).lib
 LIBWEBPDEMUX = $(DIRLIB)\$(LIBWEBPDEMUX_BASENAME).lib
+LIBSHARPYUV = $(DIRLIB)\$(LIBSHARPYUV_BASENAME).lib
 !ELSE IF "$(DLLBUILD)" == "TRUE"
-DLLINC = webp_dll.h
+CC     = $(CC) /I$(DIROBJ) $(RTLIB) /DWEBP_DLL
-CC     = $(CC) /I$(DIROBJ) /FI$(DLLINC) $(RTLIB) /DWEBP_DLL
 LIBWEBPDECODER = $(DIRLIB)\$(LIBWEBPDECODER_BASENAME)_dll.lib
 LIBWEBP = $(DIRLIB)\$(LIBWEBP_BASENAME)_dll.lib
 LIBWEBPMUX = $(DIRLIB)\$(LIBWEBPMUX_BASENAME)_dll.lib
 LIBWEBPDEMUX = $(DIRLIB)\$(LIBWEBPDEMUX_BASENAME)_dll.lib
+LIBSHARPYUV = $(DIRLIB)\$(LIBSHARPYUV_BASENAME)_dll.lib
 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
@@ -175,6 +180,15 @@ CFGSET = TRUE
 # A config was provided, so the library can be built.
 #
 
+SHARPYUV_OBJS = \
+    $(DIROBJ)\sharpyuv\sharpyuv.obj \
+    $(DIROBJ)\sharpyuv\sharpyuv_cpu.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_dec.obj \
     $(DIROBJ)\dec\buffer_dec.obj \
@@ -216,6 +230,7 @@ DSP_DEC_OBJS = \
     $(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 \
@@ -239,9 +254,9 @@ 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_avx2.obj \
     $(DIROBJ)\dsp\enc_mips32.obj \
     $(DIROBJ)\dsp\enc_mips_dsp_r2.obj \
     $(DIROBJ)\dsp\enc_msa.obj \
@@ -308,6 +323,7 @@ ENC_OBJS = \
 EXTRAS_OBJS = \
     $(DIROBJ)\extras\extras.obj \
     $(DIROBJ)\extras\quality_estimate.obj \
+    $(DIROBJ)\extras\sharpyuv_risk_table.obj \
 
 IMAGEIO_UTIL_OBJS = \
     $(DIROBJ)\imageio\imageio_util.obj \
@@ -323,6 +339,7 @@ UTILS_DEC_OBJS = \
     $(DIROBJ)\utils\color_cache_utils.obj \
     $(DIROBJ)\utils\filters_utils.obj \
     $(DIROBJ)\utils\huffman_utils.obj \
+    $(DIROBJ)\utils\palette.obj \
     $(DIROBJ)\utils\quant_levels_dec_utils.obj \
     $(DIROBJ)\utils\rescaler_utils.obj \
     $(DIROBJ)\utils\random_utils.obj \
@@ -335,12 +352,13 @@ UTILS_ENC_OBJS = \
     $(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) \
+LIBWEBP_OBJS = $(LIBWEBPDECODER_OBJS) $(ENC_OBJS) \
-               $(UTILS_ENC_OBJS) $(DLL_OBJS)
+               $(DSP_ENC_OBJS) $(UTILS_ENC_OBJS) $(DLL_OBJS)
 LIBWEBPMUX_OBJS = $(MUX_OBJS) $(LIBWEBPMUX_OBJS)
 LIBWEBPDEMUX_OBJS = $(DEMUX_OBJS) $(LIBWEBPDEMUX_OBJS)
+LIBSHARPYUV_OBJS = $(SHARPYUV_OBJS)
 
-OUT_LIBS = $(LIBWEBPDECODER) $(LIBWEBP)
+OUT_LIBS = $(LIBWEBPDECODER) $(LIBWEBP) $(LIBSHARPYUV)
 !IF "$(ARCH)" == "ARM"
 ex: $(OUT_LIBS)
 all: ex
@@ -368,7 +386,7 @@ $(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)\cwebp.exe: $(LIBWEBPDEMUX) $(LIBSHARPYUV)
 $(DIRBIN)\dwebp.exe: $(DIROBJ)\examples\dwebp.obj $(IMAGEIO_DEC_OBJS)
 $(DIRBIN)\dwebp.exe: $(IMAGEIO_ENC_OBJS)
 $(DIRBIN)\dwebp.exe: $(IMAGEIO_UTIL_OBJS)
@@ -386,13 +404,19 @@ $(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)\img2webp.exe: $(LIBWEBPDEMUX) $(LIBWEBP) $(LIBSHARPYUV)
 $(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) $(LIBWEBP)
+$(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)
@@ -403,17 +427,16 @@ $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS): $(OUTPUT_DIRS)
 $(IMAGEIO_DEC_OBJS) $(IMAGEIO_ENC_OBJS) $(EXTRAS_OBJS): $(OUTPUT_DIRS)
 !ENDIF  # ARCH == ARM
 
+$(LIBSHARPYUV): $(LIBSHARPYUV_OBJS)
 $(LIBWEBPDECODER): $(LIBWEBPDECODER_OBJS)
-$(LIBWEBP): $(LIBWEBP_OBJS)
+$(LIBWEBP): $(LIBWEBP_OBJS) $(LIBSHARPYUV)
 $(LIBWEBPMUX): $(LIBWEBPMUX_OBJS)
 $(LIBWEBPDEMUX): $(LIBWEBPDEMUX_OBJS)
 
-$(LIBWEBP_OBJS) $(LIBWEBPMUX_OBJS) $(LIBWEBPDEMUX_OBJS): $(OUTPUT_DIRS)
+$(LIBWEBP_OBJS) $(LIBWEBPMUX_OBJS) $(LIBWEBPDEMUX_OBJS) $(LIBSHARPYUV_OBJS): \
+    $(OUTPUT_DIRS)
 
 !IF "$(DLLBUILD)" == "TRUE"
-$(LIBWEBP_OBJS) $(LIBWEBPMUX_OBJS) $(LIBWEBPDEMUX_OBJS): \
-    $(DIROBJ)\$(DLLINC)
-
 {$(DIROBJ)}.c{$(DIROBJ)}.obj:
 	$(CC) $(CFLAGS) /Fd$(LIBWEBP_PDBNAME) /Fo$@  $<
 
@@ -423,20 +446,20 @@ $(LIBWEBP_OBJS) $(LIBWEBPMUX_OBJS) $(LIBWEBPDEMUX_OBJS): \
 	$(RC) /fo$@ $<
 {src\mux}.rc{$(DIROBJ)\mux}.res:
 	$(RC) /fo$@ $<
+{sharpyuv}.rc{$(DIROBJ)\sharpyuv}.res:
+	$(RC) /fo$@ $<
 
-$(LIBWEBP): $(DIROBJ)\$(LIBWEBP_BASENAME:_debug=).res
+$(LIBSHARPYUV): $(DIROBJ)\sharpyuv\$(LIBSHARPYUV_BASENAME:_debug=).res
+$(LIBWEBP): $(LIBSHARPYUV) $(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) $(LIBWEBPDEMUX):
+$(LIBWEBPDECODER) $(LIBWEBP) $(LIBWEBPMUX) $(LIBWEBPDEMUX) $(LIBSHARPYUV):
 	$(LNKDLL) /out:$(DIRBIN)\$(@B:_dll=.dll) /implib:$@ $(LFLAGS) $**
 	-xcopy $(DIROBJ)\*.pdb $(DIRLIB) /y
-
-clean::
-	@-erase /s $(DIROBJ)\$(DLLINC) 2> NUL
 !ELSE
-$(LIBWEBPDECODER) $(LIBWEBP) $(LIBWEBPMUX) $(LIBWEBPDEMUX):
+$(LIBWEBPDECODER) $(LIBWEBP) $(LIBWEBPMUX) $(LIBWEBPDEMUX) $(LIBSHARPYUV):
 	$(LNKLIB) /out:$@ $**
 	-xcopy $(DIROBJ)\*.pdb $(DIRLIB) /y
 !ENDIF
@@ -444,19 +467,9 @@ $(LIBWEBPDECODER) $(LIBWEBP) $(LIBWEBPMUX) $(LIBWEBPDEMUX):
 $(OUTPUT_DIRS):
 	@if not exist "$(@)" mkdir "$(@)"
 
-# generate a helper include to define WEBP_EXTERN suitable for the DLL build
-$(DIROBJ)\$(DLLINC):
-	@echo #ifndef WEBP_DLL_H_ > $@
-	@echo #define WEBP_DLL_H_ >> $@
-	@echo #define WEBP_EXTERN __declspec(dllexport) >> $@
-	@echo #endif  /* WEBP_DLL_H_ */ >> $@
-
 .SUFFIXES: .c .obj .res .exe
 # File-specific flag builds. Note batch rules take precedence over wildcards,
 # so for now name each file individually.
-$(DIROBJ)\dsp\enc_avx2.obj: src\dsp\enc_avx2.c
-	$(CC) $(CFLAGS) $(AVX2_FLAGS) /Fd$(LIBWEBP_PDBNAME) /Fo$(DIROBJ)\dsp\ \
-	  src\dsp\$(@B).c
 $(DIROBJ)\examples\anim_diff.obj: examples\anim_diff.c
 	$(CC) $(CFLAGS) /DWEBP_HAVE_GIF /Fd$(LIBWEBP_PDBNAME) \
 	  /Fo$(DIROBJ)\examples\ examples\$(@B).c
@@ -479,6 +492,8 @@ $(DIROBJ)\examples\gifdec.obj: examples\gifdec.c
 	$(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::
@@ -492,17 +507,16 @@ $(DIROBJ)\examples\gifdec.obj: examples\gifdec.c
 {src\utils}.c{$(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) $(LDFLAGS) /OUT:$@ $** \
+	$(LNKEXE) $(LDFLAGS) /OUT:$@ $** $(LNKLIBS)
-	    ole32.lib windowscodecs.lib shlwapi.lib
-	$(MT) -manifest $@.manifest -outputresource:$@;1
-	del $@.manifest
 
 {$(DIROBJ)\extras}.obj{$(DIRBIN)}.exe:
-	$(LNKEXE) $(LDFLAGS) /OUT:$@ $** \
+	$(LNKEXE) $(LDFLAGS) /OUT:$@ $** $(LNKLIBS)
-	    ole32.lib windowscodecs.lib shlwapi.lib
-	$(MT) -manifest $@.manifest -outputresource:$@;1
-	del $@.manifest
 
 clean::
 	@-erase /s $(DIROBJ)\*.dll 2> NUL

NEWS

@@ -1,3 +1,134 @@
+- 4/12/2024: version 1.4.0
+  This is a binary compatible release.
+  * API changes:
+    - libwebpmux: WebPAnimEncoderSetChunk, WebPAnimEncoderGetChunk,
+                  WebPAnimEncoderDeleteChunk
+    - libsharpyuv: SharpYuvOptionsInit, SharpYuvConvertWithOptions
+    - extras: SharpYuvEstimate420Risk
+  * further security related hardening in libwebp & examples
+  * some minor optimizations in the lossless encoder
+  * added WEBP_NODISCARD to report unused result warnings; enable with
+    -DWEBP_ENABLE_NODISCARD=1
+  * improvements and corrections in webp-container-spec.txt and
+    webp-lossless-bitstream-spec.txt (#611)
+  * miscellaneous warning, bug & build fixes (#615, #619, #632, #635)
+
+- 9/13/2023: version 1.3.2
+  This is a binary compatible release.
+  * security fix for lossless decoder (chromium: #1479274, CVE-2023-4863)
+
+- 6/23/2023: version 1.3.1
+  This is a binary compatible release.
+  * security fixes for lossless encoder (#603, chromium: #1420107, #1455619,
+    CVE-2023-1999)
+  * improve error reporting through WebPPicture error codes
+  * fix upsampling for RGB565 and RGBA4444 in NEON builds
+  * img2webp: add -sharp_yuv & -near_lossless
+  * Windows builds:
+    - fix compatibility with clang-cl (#607)
+    - improve Arm64 performance with cl.exe
+    - add Arm64EC support
+  * fix webp_js with emcc >= 3.1.27 (stack size change, #614)
+  * CMake fixes (#592, #610, #612)
+  * further updates to the container and lossless bitstream docs (#581, #611)
+
+- 12/16/2022: version 1.3.0
+  This is a binary compatible release.
+  * add libsharpyuv, which exposes -sharp_yuv/config.use_sharp_yuv
+    functionality to other libraries; libwebp now depends on this library
+  * major updates to the container and lossless bitstream docs (#448, #546,
+    #551)
+  * miscellaneous warning, bug & build fixes (#576, #583, #584)
+
+- 8/4/2022: version 1.2.4
+  This is a binary compatible release.
+  * restore CMake libwebpmux target name for compatibility with 1.2.2 (#575)
+  * fix lossless crunch mode encoding with WEBP_REDUCE_SIZE
+    (chromium: #1345547, #1345595, #1345772, #1345804)
+
+- 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

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

@@ -1,782 +0,0 @@
-          __   __  ____  ____  ____
-         /  \\/  \/  _ \/  _ )/  _ \
-         \       /   __/  _  \   __/
-          \__\__/\____/\_____/__/ ____  ___
-                / _/ /    \    \ /  _ \/ _/
-               /  \_/   / /   \ \   __/  \__
-               \____/____/\_____/_____/____/v1.0.0
-
-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
-
-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 http://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:
-=========
-
-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:
----------------------
-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:
-$ 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.
-
-./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/
-
-# 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="$MIPS_LDFLAGS"
-make
-make install
-
-CMake:
-------
-With CMake, you can compile libwebp, cwebp, dwebp, gif2web, img2webp, webpinfo
-and the JS bindings.
-
-Prerequisites:
-A compiler (e.g., gcc with autotools) and CMake.
-On a Debian-like system the following should install everything you need for a
-minimal build:
-$ sudo apt-get install build-essential cmake
-
-When building from git sources, you will need to run cmake to generate the
-makefiles.
-
-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.:
-
-cmake -DWEBP_BUILD_CWEBP=ON -DWEBP_BUILD_DWEBP=ON ../
-
-or through your favorite interface (like ccmake or cmake-qt-gui).
-
-Finally, once installed, you can also use WebP in your CMake project by doing:
-
-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:
-$ 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. :
-
-./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 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, TIFF or WebP file.
-
-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)
-  -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:
-
- 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)
-  -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> ......... scale the 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: 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: 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
-  -mt .......... use multi-threading
-  -info ........ print info
-  -h ........... this help message
-
-Keyboard shortcuts:
-  'c' ................ toggle use of color profile
-  '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)
-  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
-
-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:
-
-  img2webp [file-level options] [image files...] [per-frame options...]
-
-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
-
-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)
-  -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:
-$ make -f makefile.unix examples/gif2webp
-
-or using autoconf:
-$ ./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: 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 and a C++ compiler installed, anim_diff can
-be built using makefile.unix:
-$ make -f makefile.unix examples/anim_diff
-
-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;
-  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);
-
--------------------------------------- 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 the issue tracker:
-    https://bugs.chromium.org/p/webp
-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 +1,54 @@
+# WebP Codec
+
+```
+      __   __  ____  ____  ____
+     /  \\/  \/  _ \/  _ )/  _ \
+     \       /   __/  _  \   __/
+      \__\__/\____/\_____/__/ ____  ___
+            / _/ /    \    \ /  _ \/ _/
+           /  \_/   / /   \ \   __/  \__
+           \____/____/\_____/_____/____/v1.4.0
+```
+
+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://issues.webmproject.org).
+For security reports, select 'Security report' from the Template dropdown.
+
+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

@@ -1,227 +0,0 @@
-          __   __  ____  ____  ____  __ __  _     __ __
-         /  \\/  \/  _ \/  _ \/  _ \/  \  \/ \___/_ / _\
-         \       /   __/  _  \   __/      /  /  (_/  /__
-          \__\__/\_____/_____/__/  \__//_/\_____/__/___/v1.0.0
-
-
-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 -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:
-   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 each 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 '-'.
-
-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).
-
-AnimEncoder API:
-================
-The AnimEncoder API can be used to create animated WebP images.
-
-Code example:
-
-  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).
-
-
-Bugs:
-=====
-
-Please report all bugs to the issue tracker:
-    https://bugs.chromium.org/p/webp
-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.webp_js

@@ -1,76 +0,0 @@
-     __   __ ____ ____ ____     __  ____
-    /  \\/  \  _ \  _ \  _ \   (__)/  __\
-    \       /  __/ _  \  __/   _)  \_   \
-     \__\__/_____/____/_/     /____/____/
-
-Description:
-============
-
-This file describes the compilation of libwebp into a JavaScript decoder
-using Emscripten and CMake.
-
- - install the Emscripten SDK following the procedure described at:
-   https://kripken.github.io/emscripten-site/docs/getting_started/downloads.html
-   After installation, you should have some global variable positioned to the
-   location of the SDK. In particular, $EMSCRIPTEN should point to the
-   top-level directory containing Emscripten tools.
-
- - make sure the file $EMSCRIPTEN/cmake/Modules/Platform/Emscripten.cmake is
-   accessible. This is the toolchain file used by CMake to invoke Emscripten.
-
- - configure the project 'WEBP_JS' with CMake using:
-
- cd webp_js && \
- cmake -DWEBP_BUILD_WEBP_JS=ON \
-       -DEMSCRIPTEN_GENERATE_BITCODE_STATIC_LIBRARIES=1 \
-       -DCMAKE_TOOLCHAIN_FILE=$EMSCRIPTEN/cmake/Modules/Platform/Emscripten.cmake \
-       ../
-
- - compile webp.js using 'make'.
-
- - that's it! Upon completion, you should have the webp.js and
-   webp.js.mem files generated.
-
-The callable JavaScript function is WebPToSDL(), which decodes a raw WebP
-bitstream into a canvas. See webp_js/index.html for a simple usage sample
-(see below for instructions).
-
-Demo HTML page:
-===============
-
-   The HTML page webp_js/index.html requires an HTTP server to serve the WebP
-   image example. It's easy to just use Python for that.
-
-cd webp_js && python -m SimpleHTTPServer 8080
-
-and then navigate to http://localhost:8080 in your favorite browser.
-
-
-Web-Assembly (WASM) version:
-============================
-
-  CMakeLists.txt is configured to build the WASM version when using
-  the option WEBP_BUILD_WEBP_JS=ON. The compilation step will assemble
-  the files 'webp_wasm.js', 'webp_wasm.wasm' in the webp_js/ directory.
-  See webp_js/index_wasm.html for a simple demo page using the WASM version
-  of the library.
-
-  You will need a fairly recent version of Emscripten (at least 1.37.8) and of
-  your WASM-enabled browser to run this version. Consider it very experimental!
-
-Caveat:
-=======
-
-  - First decoding using the library is usually slower, due to just-in-time
-    compilation.
-
-  - Some versions of llvm produce the following compile error when SSE2 is
-    enabled.
-
-"Unsupported:   %516 = bitcast <8 x i16> %481 to i128
- LLVM ERROR: BitCast Instruction not yet supported for integer types larger than 64 bits"
-
-    The corresponding Emscripten bug is at:
-    https://github.com/kripken/emscripten/issues/3788
-
-    Therefore, SSE2 optimization is currently disabled in CMakeLists.txt.

build.gradle

@@ -105,6 +105,14 @@ model {
       sources {
         c {
           source {
+            srcDir "sharpyuv"
+            include "sharpyuv.c"
+            include "sharpyuv_cpu.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"
@@ -141,6 +149,7 @@ model {
             include "lossless_msa.c"
             include "lossless_neon.$NEON"
             include "lossless_sse2.c"
+            include "lossless_sse41.c"
             include "rescaler.c"
             include "rescaler_mips32.c"
             include "rescaler_mips_dsp_r2.c"
@@ -164,6 +173,7 @@ model {
             include "color_cache_utils.c"
             include "filters_utils.c"
             include "huffman_utils.c"
+            include "palette.c"
             include "quant_levels_dec_utils.c"
             include "random_utils.c"
             include "rescaler_utils.c"
@@ -173,9 +183,9 @@ model {
             include "cost.c"
             include "cost_mips32.c"
             include "cost_mips_dsp_r2.c"
+            include "cost_neon.$NEON"
             include "cost_sse2.c"
             include "enc.c"
-            include "enc_avx2.c"
             include "enc_mips32.c"
             include "enc_mips_dsp_r2.c"
             include "enc_msa.c"
@@ -432,8 +442,3 @@ model {
     }
   }
 }
-
-// Task to generate the wrapper.
-task wrapper(type: Wrapper) {
-  gradleVersion = '2.13'
-}

cmake/WebPConfig.cmake.in

@@ -1,6 +1,19 @@
+set(WebP_VERSION @PROJECT_VERSION@)
+set(WEBP_VERSION ${WebP_VERSION})
+
 @PACKAGE_INIT@
 
-set(WebP_INCLUDE_DIRS "webp")
+if(@WEBP_USE_THREAD@)
-set(WEBP_INCLUDE_DIRS ${WebP_INCLUDE_DIRS})
+  include(CMakeFindDependencyMacro)
+  find_dependency(Threads REQUIRED)
+endif()
+
+include("${CMAKE_CURRENT_LIST_DIR}/@PROJECT_NAME@Targets.cmake")
+
+set_and_check(WebP_INCLUDE_DIR "@PACKAGE_CMAKE_INSTALL_INCLUDEDIR@")
+set(WebP_INCLUDE_DIRS ${WebP_INCLUDE_DIR})
+set(WEBP_INCLUDE_DIRS ${WebP_INCLUDE_DIR})
 set(WebP_LIBRARIES "@INSTALLED_LIBRARIES@")
 set(WEBP_LIBRARIES "${WebP_LIBRARIES}")
+
+check_required_components(WebP)

cmake/config.h.in

@@ -16,48 +16,18 @@
 /* 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
 
@@ -93,19 +63,9 @@
 /* Define to the version of this package. */
 #cmakedefine PACKAGE_VERSION "@PACKAGE_VERSION@"
 
-/* Define to necessary symbol if this constant uses a non-standard name on
-   your system. */
-#cmakedefine PTHREAD_CREATE_JOINABLE 1
-
-/* 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 AVX2 is supported */
-#cmakedefine WEBP_HAVE_AVX2 1
-
 /* Set to 1 if GIF library is installed */
 #cmakedefine WEBP_HAVE_GIF 1
 

cmake/cpu.cmake

@@ -1,4 +1,12 @@
-## Check for SIMD extensions.
+#  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)
@@ -10,7 +18,8 @@ function(webp_check_compiler_flag WEBP_SIMD_FLAG ENABLE_SIMD)
   unset(WEBP_HAVE_FLAG_${WEBP_SIMD_FLAG} CACHE)
   cmake_push_check_state()
   set(CMAKE_REQUIRED_INCLUDES ${CMAKE_CURRENT_SOURCE_DIR})
-  check_c_source_compiles("
+  check_c_source_compiles(
+    "
       #include \"${CMAKE_CURRENT_LIST_DIR}/../src/dsp/dsp.h\"
       int main(void) {
         #if !defined(WEBP_USE_${WEBP_SIMD_FLAG})
@@ -18,8 +27,8 @@ function(webp_check_compiler_flag WEBP_SIMD_FLAG ENABLE_SIMD)
         #endif
         return 0;
       }
-    " WEBP_HAVE_FLAG_${WEBP_SIMD_FLAG}
+    "
-  )
+    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)
@@ -29,28 +38,34 @@ function(webp_check_compiler_flag WEBP_SIMD_FLAG ENABLE_SIMD)
 endfunction()
 
 # those are included in the names of WEBP_USE_* in c++ code.
-set(WEBP_SIMD_FLAGS "SSE2;SSE41;AVX2;MIPS32;MIPS_DSP_R2;NEON;MSA")
+set(WEBP_SIMD_FLAGS "SSE41;SSE2;MIPS32;MIPS_DSP_R2;NEON;MSA")
-set(WEBP_SIMD_FILE_EXTENSIONS "_sse2.c;_sse41.c;_avx2.c;_mips32.c;_mips_dsp_r2.c;_neon.c;_msa.c")
+set(WEBP_SIMD_FILE_EXTENSIONS
-if(MSVC)
+    "_sse41.c;_sse2.c;_mips32.c;_mips_dsp_r2.c;_neon.c;_msa.c")
-  # MSVC does not have a SSE4 flag but AVX2 support implies
+if(MSVC AND CMAKE_C_COMPILER_ID STREQUAL "MSVC")
-  # SSE4 support.
+  # With at least Visual Studio 12 (2013)+ /arch is not necessary to build SSE2
-  set(SIMD_ENABLE_FLAGS "/arch:SSE2;/arch:AVX2;/arch:AVX2;;;;")
+  # 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 "-msse2;-msse4.1;-mavx2;-mips32;-mdspr2;-mfpu=neon;-mmsa")
+  set(SIMD_ENABLE_FLAGS "-msse4.1;-msse2;-mips32;-mdspr2;-mfpu=neon;-mmsa")
-  set(SIMD_DISABLE_FLAGS "-mno-sse2;-mno-sse4.1;-mno-avx2;;-mno-dspr2;;-mno-msa")
+  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(${ANDROID})
+if(ANDROID AND ANDROID_ABI)
   if(${ANDROID_ABI} STREQUAL "armeabi-v7a")
-    # This is because Android studio uses the configuration
+    # This is because Android studio uses the configuration "-march=armv7-a
-    # "-march=armv7-a -mfloat-abi=softfp -mfpu=vfpv3-d16"
+    # -mfloat-abi=softfp -mfpu=vfpv3-d16" that does not trigger neon
-    # that does not trigger neon optimizations but should
+    # optimizations but should (as this configuration does not exist anymore).
-    # (as this configuration does not exist anymore).
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mfpu=neon ")
   endif()
 endif()
@@ -59,6 +74,12 @@ list(LENGTH WEBP_SIMD_FLAGS WEBP_SIMD_FLAGS_LENGTH)
 math(EXPR WEBP_SIMD_FLAGS_RANGE "${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
@@ -69,16 +90,25 @@ foreach(I_SIMD RANGE ${WEBP_SIMD_FLAGS_RANGE})
   webp_check_compiler_flag(${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()
-    set(SIMD_COMPILE_FLAG " ")
+    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}/../"
+  file(GLOB SIMD_FILES
-    "src/dsp/*${WEBP_SIMD_FILE_EXTENSION}"
+       "${CMAKE_CURRENT_LIST_DIR}/../sharpyuv/*${WEBP_SIMD_FILE_EXTENSION}"
-  )
+       "${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})
@@ -95,6 +125,12 @@ foreach(I_SIMD RANGE ${WEBP_SIMD_FLAGS_RANGE})
       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)
@@ -106,12 +142,11 @@ foreach(I_SIMD RANGE ${WEBP_SIMD_FLAGS_RANGE})
             set(COMMON_PATTERNS)
           endif()
           set(CMAKE_REQUIRED_DEFINITIONS ${SIMD_COMPILE_FLAG})
-          check_c_source_compiles("int main(void) {return 0;}"
+          check_c_source_compiles(
-            FLAG_${SIMD_COMPILE_FLAG}
+            "int main(void) {return 0;}" FLAG_${SIMD_COMPILE_FLAG} FAIL_REGEX
-            FAIL_REGEX "warning: argument unused during compilation:"
+            "warning: argument unused during compilation:" ${COMMON_PATTERNS})
-            ${COMMON_PATTERNS}
-          )
           if(NOT FLAG_${SIMD_COMPILE_FLAG})
+            unset(HAS_COMPILE_FLAG)
             unset(HAS_COMPILE_FLAG CACHE)
           endif()
         endif()

cmake/deps.cmake

@@ -1,130 +1,137 @@
+#  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.
+# Check for compiler options.
 include(CheckCSourceCompiles)
-check_c_source_compiles("
+check_c_source_compiles(
+  "
     int main(void) {
       (void)__builtin_bswap16(0);
       return 0;
     }
   "
-  HAVE_BUILTIN_BSWAP16
+  HAVE_BUILTIN_BSWAP16)
-)
+check_c_source_compiles(
-check_c_source_compiles("
+  "
     int main(void) {
       (void)__builtin_bswap32(0);
       return 0;
     }
   "
-  HAVE_BUILTIN_BSWAP32
+  HAVE_BUILTIN_BSWAP32)
-)
+check_c_source_compiles(
-check_c_source_compiles("
+  "
     int main(void) {
       (void)__builtin_bswap64(0);
       return 0;
     }
   "
-  HAVE_BUILTIN_BSWAP64
+  HAVE_BUILTIN_BSWAP64)
-)
 
-## Check for libraries.
+# Check for libraries.
-find_package(Threads)
+if(WEBP_USE_THREAD)
-if(Threads_FOUND)
+  find_package(Threads)
-  if(CMAKE_USE_PTHREADS_INIT)
+  if(Threads_FOUND)
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pthread")
+    # work around cmake bug on QNX (https://cmake.org/Bug/view.php?id=11333)
+    if(CMAKE_USE_PTHREADS_INIT AND NOT CMAKE_SYSTEM_NAME STREQUAL "QNX")
+      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -pthread")
+    endif()
+    list(APPEND WEBP_DEP_LIBRARIES Threads::Threads)
   endif()
-  foreach(PTHREAD_TEST HAVE_PTHREAD_PRIO_INHERIT PTHREAD_CREATE_UNDETACHED)
+  set(WEBP_USE_THREAD ${Threads_FOUND})
-    check_c_source_compiles("
-        #include <pthread.h>
-        int main (void) {
-          int attr = ${PTHREAD_TEST};
-          return attr;
-        }
-      " ${PTHREAD_TEST}
-    )
-  endforeach()
-  list(APPEND WEBP_DEP_LIBRARIES ${CMAKE_THREAD_LIBS_INIT})
 endif()
-set(WEBP_USE_THREAD ${Threads_FOUND})
 
 # TODO: this seems unused, check with autotools.
 set(LT_OBJDIR ".libs/")
 
 # Only useful for vwebp, so useless for now.
-# find_package(OpenGL)
+find_package(OpenGL)
-# set(WEBP_HAVE_GL ${OPENGL_FOUND})
+set(WEBP_HAVE_GL ${OPENGL_FOUND})
-# set(WEBP_DEP_INCLUDE_DIRS ${WEBP_DEP_INCLUDE_DIRS} ${OPENGL_INCLUDE_DIRS})
-# set(WEBP_DEP_LIBRARIES ${WEBP_DEP_LIBRARIES} ${OPENGL_LIBRARIES})
 
-# Find the standard C math library.
+# Check if we need to link to the C math library. We do not look for it as it is
-find_library(MATH_LIBRARY NAMES m)
+# not found when cross-compiling, while it is here.
-if(MATH_LIBRARY)
+check_c_source_compiles(
-  list(APPEND WEBP_DEP_LIBRARIES ${MATH_LIBRARY})
+  "
+    #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 SHARPYUV_DEP_LIBRARIES m)
+  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)
+if(WEBP_FIND_IMG_LIBS)
-  find_package(${I_LIB})
+  foreach(I_LIB PNG JPEG TIFF)
-  set(WEBP_HAVE_${I_LIB} ${${I_LIB}_FOUND})
+    # Disable tiff when compiling in static mode as it is failing on Ubuntu.
-  if(${I_LIB}_FOUND)
+    if(WEBP_LINK_STATIC AND ${I_LIB} STREQUAL "TIFF")
-    list(APPEND WEBP_DEP_IMG_LIBRARIES ${${I_LIB}_LIBRARIES})
+      message(STATUS "TIFF is disabled when statically linking.")
-    list(APPEND WEBP_DEP_IMG_INCLUDE_DIRS
+      continue()
-         ${${I_LIB}_INCLUDE_DIR} ${${I_LIB}_INCLUDE_DIRS})
+    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()
-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.
+  # GIF detection, gifdec isn't part of the imageio lib.
-include(CMakePushCheckState)
+  include(CMakePushCheckState)
-set(WEBP_DEP_GIF_LIBRARIES)
+  set(WEBP_DEP_GIF_LIBRARIES)
-set(WEBP_DEP_GIF_INCLUDE_DIRS)
+  set(WEBP_DEP_GIF_INCLUDE_DIRS)
-find_package(GIF)
+  find_package(GIF)
-set(WEBP_HAVE_GIF ${GIF_FOUND})
+  set(WEBP_HAVE_GIF ${GIF_FOUND})
-if(GIF_FOUND)
+  if(GIF_FOUND)
-  # GIF find_package only locates the header and library, it doesn't fail
+    # 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
+    # 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
+    # least cmake 3.7.2). Make sure the library links to avoid incorrect
-  # detection when cross compiling.
+    # detection when cross compiling.
-  cmake_push_check_state()
+    cmake_push_check_state()
-  set(CMAKE_REQUIRED_LIBRARIES ${GIF_LIBRARIES})
+    set(CMAKE_REQUIRED_LIBRARIES ${GIF_LIBRARIES})
-  set(CMAKE_REQUIRED_INCLUDES ${GIF_INCLUDE_DIR})
+    set(CMAKE_REQUIRED_INCLUDES ${GIF_INCLUDE_DIR})
-  check_c_source_compiles("
+    check_c_source_compiles(
+      "
       #include <gif_lib.h>
       int main(void) {
         (void)DGifOpenFileHandle;
         return 0;
       }
-      " GIF_COMPILES
+      "
-  )
+      GIF_COMPILES)
-  cmake_pop_check_state()
+    cmake_pop_check_state()
-  if(GIF_COMPILES)
+    if(GIF_COMPILES)
-    list(APPEND WEBP_DEP_GIF_LIBRARIES ${GIF_LIBRARIES})
+      list(APPEND WEBP_DEP_GIF_LIBRARIES ${GIF_LIBRARIES})
-    list(APPEND WEBP_DEP_GIF_INCLUDE_DIRS ${GIF_INCLUDE_DIR})
+      list(APPEND WEBP_DEP_GIF_INCLUDE_DIRS ${GIF_INCLUDE_DIR})
-  else()
+    else()
-    unset(GIF_FOUND)
+      unset(GIF_FOUND)
+    endif()
   endif()
 endif()
 
-## Check for specific headers.
+# 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)
@@ -134,18 +141,17 @@ if(HAVE_WINCODEC_H)
   list(APPEND WEBP_DEP_LIBRARIES shlwapi ole32 windowscodecs)
 endif()
 
-## Check for SIMD extensions.
+# Check for SIMD extensions.
 include(${CMAKE_CURRENT_LIST_DIR}/cpu.cmake)
 
-## Define extra info.
+# 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\\.:/]*)\\]"
+string(REGEX MATCHALL "\\[([0-9a-z\\.:/]*)\\]" CONFIGURE_AC_PACKAGE_INFO
-  CONFIGURE_AC_PACKAGE_INFO ${CONFIGURE_AC}
+             ${CONFIGURE_AC})
-)
 function(strip_bracket VAR)
   string(LENGTH ${${VAR}} TMP_LEN)
   math(EXPR TMP_LEN ${TMP_LEN}-2)

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

@@ -1,6 +1,6 @@
-AC_INIT([libwebp], [1.0.0],
+AC_INIT([libwebp], [1.4.0],
-        [https://bugs.chromium.org/p/webp],,
+        [https://issues.webmproject.org],,
-        [http://developers.google.com/speed/webp])
+        [https://developers.google.com/speed/webp])
 AC_CANONICAL_HOST
 AC_PREREQ([2.60])
 AM_INIT_AUTOMAKE([-Wall foreign subdir-objects])
@@ -9,7 +9,8 @@ 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
 
@@ -27,11 +28,46 @@ 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)
@@ -70,6 +106,7 @@ 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], [-Wextra-semi-stmt])
 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])
@@ -79,7 +116,9 @@ 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], [-Wstrict-prototypes])
 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])
@@ -122,31 +161,6 @@ AS_IF([test "$GCC" = "yes" ], [
 AC_SUBST([AM_CFLAGS])
 
 dnl === Check for machine specific flags
-AC_ARG_ENABLE([avx2],
-              AS_HELP_STRING([--disable-avx2],
-                             [Disable detection of AVX2 support
-                              @<:@default=auto@:>@]))
-
-AS_IF([test "x$enable_avx2" != "xno" -a "x$enable_sse4_1" != "xno" \
-         -a "x$enable_sse2" != "xno"], [
-  AVX2_CFLAGS="$INTRINSICS_CFLAGS $AVX2_FLAGS"
-  TEST_AND_ADD_CFLAGS([AVX2_FLAGS], [-mavx2])
-  AS_IF([test -n "$AVX2_FLAGS"], [
-    SAVED_CFLAGS=$CFLAGS
-    CFLAGS="$CFLAGS $AVX2_FLAGS"
-    AC_CHECK_HEADER([immintrin.h],
-                    [AC_DEFINE(WEBP_HAVE_AVX2, [1],
-                     [Set to 1 if AVX2 is supported])],
-                    [AVX2_FLAGS=""],
-                    dnl it's illegal to directly include avx2intrin.h, but it's
-                    dnl included conditionally in immintrin.h, tricky!
-                    [#ifndef __AVX2__
-                     #error avx2 is not enabled
-                     #endif
-                    ])
-    CFLAGS=$SAVED_CFLAGS])
-  AC_SUBST([AVX2_FLAGS])])
-
 AC_ARG_ENABLE([sse4.1],
               AS_HELP_STRING([--disable-sse4.1],
                              [Disable detection of SSE4.1 support
@@ -249,6 +263,9 @@ AS_IF([test "x$enable_neon" != "xno"], [
         *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])])
 
@@ -433,6 +450,10 @@ AS_IF([test "x$enable_gl" != "xno"], [
 
   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 "$build_vwebp" = "yes"])
@@ -445,7 +466,7 @@ AC_ARG_ENABLE([sdl],
                               @<:@default=auto@:>@]))
 AS_IF([test "x$enable_sdl" != "xno"], [
   CLEAR_LIBVARS([SDL])
-  AC_PATH_PROGS([LIBSDL_CONFIG], [sdl-config])
+  AC_PATH_PROGS([LIBSDL_CONFIG], [sdl2-config])
   if test -n "$LIBSDL_CONFIG"; then
     SDL_INCLUDES=`$LIBSDL_CONFIG --cflags`
     SDL_LIBS="`$LIBSDL_CONFIG --libs`"
@@ -455,13 +476,12 @@ AS_IF([test "x$enable_sdl" != "xno"], [
 
   sdl_header="no"
   LIBCHECK_PROLOGUE([SDL])
-  AC_CHECK_HEADER([SDL/SDL.h], [sdl_header="SDL/SDL.h"],
+  AC_CHECK_HEADER([SDL2/SDL.h], [sdl_header="SDL2/SDL.h"],
-                  [AC_CHECK_HEADER([SDL.h], [sdl_header="SDL.h"],
+                  [AC_MSG_WARN(SDL2 library not available - no 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
+    for lib in "" "-lSDL2" "-lSDL2main -lSDL2"; do
       LIBS="$SDL_SAVED_LIBS $lib"
       # Perform a full link to ensure SDL_main is resolved if needed.
       AC_LINK_IFELSE(
@@ -492,7 +512,7 @@ AS_IF([test "x$enable_sdl" != "xno"], [
   if test x"$sdl_support" = "xyes"; then
     build_vwebp_sdl=yes
   else
-    AC_MSG_WARN(Optional SDL library not found)
+    AC_MSG_NOTICE([Not building vwebp-sdl. SDL library is required.])
   fi
 ])
 
@@ -616,11 +636,17 @@ AS_IF([test "x$enable_gif" != "xno"], [
   if test "$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 "${build_anim_diff}" = "yes"])
@@ -628,11 +654,17 @@ AM_CONDITIONAL([BUILD_GIF2WEBP], [test "${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"])
 
@@ -716,52 +748,23 @@ else
   AC_MSG_RESULT([no])
 fi
 
-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([--disable-libwebpdemux],
-                             [Disable libwebpdemux @<:@default=no@:>@]),
-              [], [enable_libwebpdemux=yes])
-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 === 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(${enable_libwebpextras-no})
-AM_CONDITIONAL([WANT_EXTRAS], [test "$enable_libwebpextras" = "yes"])
-
 dnl =========================
 
+dnl Add an empty webp_libname_prefix variable for use in *.pc.in.
+AC_SUBST([webp_libname_prefix])
 AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_HEADERS([src/webp/config.h])
 AC_CONFIG_FILES([Makefile src/Makefile man/Makefile \
                  examples/Makefile extras/Makefile imageio/Makefile \
+                 sharpyuv/Makefile sharpyuv/libsharpyuv.pc \
                  src/dec/Makefile src/enc/Makefile src/dsp/Makefile \
                  src/demux/Makefile src/mux/Makefile \
                  src/utils/Makefile \
                  src/libwebp.pc src/libwebpdecoder.pc \
                  src/demux/libwebpdemux.pc src/mux/libwebpmux.pc])
 
-
+dnl fix exports from MinGW builds
+AC_CONFIG_COMMANDS_POST([$SED -i 's/-DDLL_EXPORT/-DWEBP_DLL/' config.status])
 AC_OUTPUT
 
 AC_MSG_NOTICE([

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: WebPIDelete(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 +1,231 @@
+# 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="$MIPS_LDFLAGS"
+make
+make install
+```
+
+## Building libwebp - Using vcpkg
+
+You can download and install libwebp using the
+[vcpkg](https://github.com/Microsoft/vcpkg) dependency manager:
+
+```shell
+git clone https://github.com/Microsoft/vcpkg.git
+cd vcpkg
+./bootstrap-vcpkg.sh
+./vcpkg integrate install
+./vcpkg install libwebp
+```
+
+The libwebp port in vcpkg is kept up to date by Microsoft team members and
+community contributors. If the version is out of date, please
+[create an issue or pull request](https://github.com/Microsoft/vcpkg) on the
+vcpkg repository.
+
+## CMake
+
+With CMake, you can compile libwebp, cwebp, dwebp, gif2webp, img2webp, webpinfo
+and the JS bindings.
+
+Prerequisites: a compiler (e.g., gcc with autotools) and CMake.
+
+On a Debian-like system the following should install everything you need for a
+minimal build:
+
+```shell
+$ 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](../webp_js/README.md)

doc/specs_generation.md

@@ -0,0 +1,27 @@
+# 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 \
+  -x syntax-coderay --syntax-highlighter coderay \
+  --syntax-highlighter-opts "{default_lang: c, line_numbers: , css: style}" \
+  > doc/output/webp-lossless-bitstream-spec.html
+```
+
+Optimally, use kramdown 0.13.7 or newer if syntax highlighting desired.

doc/tools.md

@@ -0,0 +1,519 @@
+# 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]... [-o webp_file]
+```
+
+File-level options (only used at the start of compression):
+
+```
+-min_size ............ minimize size
+-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
+-near_lossless <int> . use near-lossless image preprocessing
+                       (0..100=off), default=100
+-sharp_yuv ........... use sharper (and slower) RGB->YUV conversion
+                       (lossy only)
+-loop <int> .......... loop count (default: 0, = infinite loop)
+-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
+-exact, -noexact ..... preserve or alter RGB values in transparent area
+                       (default: -noexact, may cause artifacts
+                                 with lossy animations)
+```
+
+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
+See the accompanying specs_generation.md. External link targets are referenced
-end of this file.
+at the end of this file.
 
 -->
 
@@ -20,50 +20,48 @@ WebP Container Specification
 Introduction
 ------------
 
-WebP is an image format that uses either (i) the VP8 key frame encoding
+WebP is an image format that uses either (i) the VP8 key frame encoding to
-to compress image data in a lossy way, or (ii) the WebP lossless encoding
+compress image data in a lossy way or (ii) the WebP lossless encoding. These
-(and possibly other encodings in the future). These encoding schemes should
+encoding schemes should make it more efficient than older formats, such as JPEG,
-make it more efficient than currently used formats. It is optimized for fast
+GIF, and PNG. It is optimized for fast image transfer over the network (for
-image transfer over the network (e.g., for websites). The WebP format has
+example, for websites). The WebP format has feature parity (color profile,
-feature parity (color profile, metadata, animation etc) with other formats as
+metadata, animation, etc.) with other formats as well. This document describes
-well. This document describes the structure of a WebP file.
+the structure of a WebP file.
 
-The WebP container (i.e., RIFF container for WebP) allows feature support over
+The WebP container (that is, the RIFF container for WebP) allows feature support
-and above the basic use case of WebP (i.e., a file containing a single image
+over and above the basic use case of WebP (that is, a file containing a single
-encoded as a VP8 key frame). The WebP container provides additional support
+image encoded as a VP8 key frame). The WebP container provides additional
-for:
+support for the following:
 
-  * **Lossless compression.** An image can be losslessly compressed, using the
+  * 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 Exchangeable Image File
+    Format (Exif) or Extensible Metadata Platform (XMP) format.
 
-  * **Transparency.** An image may have transparency, i.e., an alpha channel.
+  * Transparency: An image may have transparency, that is, an alpha channel.
 
-  * **Color Profile.** An image may have an embedded ICC profile as described
+  * Color Profile: An image may have an embedded ICC profile as described
     by the [International Color Consortium][iccspec].
 
-  * **Animation.** An image may have multiple frames with pauses between them,
+  * Animation: An image may have multiple frames with pauses between them,
     making it an animation.
 
-The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
+Terminology & Basics
-"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
+--------------------
-document are to be interpreted as described in [RFC 2119][].
+
+The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD",
+"SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this
+document are to be interpreted as described in BCP 14 [RFC 2119][] [RFC 8174][]
+when, and only when, they appear in all capitals, as shown here.
+
+A WebP file contains either a still image (that is, an encoded matrix of pixels)
+or an [animation](#animation). Optionally, it can also contain transparency
+information, a color profile and metadata. We refer to the matrix of pixels as
+the _canvas_ of the image.
 
 Bit numbering in chunk diagrams starts at `0` for the most significant bit
-('MSB 0') as described in [RFC 1166][].
+('MSB 0'), as described in [RFC 1166][].
-
-**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.
-
-Terminology & Basics
-------------------------
-
-A WebP file contains either a still image (i.e., an encoded matrix of pixels)
-or an [animation](#animation). Optionally, it can also contain transparency
-information, color profile and metadata. In case we need to refer only to the
-matrix of pixels, we will call it the _canvas_ of the image.
 
 Below are additional terms used throughout this document:
 
@@ -86,19 +84,25 @@ _uint32_
 
 _FourCC_
 
-: A _FourCC_ (four-character code) is a _uint32_ created by concatenating four
+: A four-character code (FourCC) is a _uint32_ created by concatenating four
-  ASCII characters in little-endian order.
+  ASCII characters in little-endian order. This means 'aaaa' (0x61616161) and
+ 'AAAA' (0x41414141) are treated as different _FourCCs_.
 
 _1-based_
 
-: An unsigned integer field storing values offset by `-1`. e.g., Such a field
+: An unsigned integer field storing values offset by `-1`, for example, such a
-  would store value _25_ as _24_.
+  field would store value _25_ as _24_.
+
+_ChunkHeader('ABCD')_
+
+: Used to describe the _FourCC_ and _Chunk Size_ header of individual chunks,
+  where 'ABCD' is the FourCC for the chunk. This element's size is 8 bytes.
 
 
 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:
@@ -110,7 +114,7 @@ The basic element of a RIFF file is a _chunk_. It consists of:
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          Chunk Size                           |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                         Chunk Payload                         |
+    :                         Chunk Payload                         :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
 Chunk FourCC: 32 bits
@@ -119,21 +123,15 @@ Chunk FourCC: 32 bits
 
 Chunk Size: 32 bits (_uint32_)
 
-: The size of the chunk not including this field, the chunk identifier or
+: The size of the chunk in bytes, not including this field, the chunk
-  padding.
+  identifier, or padding.
 
 Chunk Payload: _Chunk Size_ bytes
 
-: The data payload. If _Chunk Size_ is odd, a single padding byte -- that
+: The data payload. If _Chunk Size_ is odd, a single padding byte -- which MUST
-  SHOULD be `0` -- is added.
+  be `0` to conform with RIFF -- is added.
 
-_ChunkHeader('ABCD')_
+**Note**: RIFF has a convention that all-uppercase chunk FourCCs are standard
-
-: This is used to describe the _FourCC_ and _Chunk Size_ header of individual
-  chunks, where 'ABCD' is the FourCC for the chunk. This element's
-  size is 8 bytes.
-
-**Note:** RIFF has a convention that all-uppercase chunk FourCCs are standard
 chunks that apply to any RIFF file format, while FourCCs specific to a file
 format are all lowercase. WebP does not follow this convention.
 
@@ -153,23 +151,25 @@ WebP File Header
 
 'RIFF': 32 bits
 
-: The ASCII characters 'R' 'I' 'F' 'F'.
+: The ASCII characters 'R', 'I', 'F', 'F'.
 
 File Size: 32 bits (_uint32_)
 
-: The size of the file in bytes starting at offset 8. The maximum value of
+: 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.
+  most 4 GiB minus 2 bytes.
 
 'WEBP': 32 bits
 
-: The ASCII characters 'W' 'E' 'B' 'P'.
+: The ASCII characters 'W', 'E', 'B', 'P'.
 
 A WebP file MUST begin with a RIFF header with the FourCC 'WEBP'. The file size
 in the header is the total size of the chunks that follow plus `4` bytes for
-the 'WEBP' FourCC. The file SHOULD NOT contain anything after it. As the size
+the 'WEBP' FourCC. The file SHOULD NOT contain any data after the data
-of any chunk is even, the size given by the RIFF header is also even. The
+specified by _File Size_. Readers MAY parse such files, ignoring the trailing
-contents of individual chunks will be described in the following sections.
+data. As the size of any chunk is even, the size given by the RIFF header is
+also even. The contents of individual chunks are described in the following
+sections.
 
 
 Simple File Format (Lossy)
@@ -184,37 +184,43 @@ Simple WebP (lossy) file format:
      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    |                                                               |
     |                    WebP file header (12 bytes)                |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                          VP8 chunk                            |
+    :                        'VP8 ' Chunk                           :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
-VP8 chunk:
+'VP8 ' Chunk:
 
      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('VP8 ')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                           VP8 data                            |
+    :                           VP8 data                            :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
 VP8 data: _Chunk Size_ bytes
 
 : VP8 bitstream data.
 
-The VP8 bitstream format specification can be found at [VP8 Data Format and
+Note that the fourth character in the 'VP8 ' FourCC is an ASCII space (0x20).
-Decoding Guide][vp8spec]. Note that the VP8 frame header contains the VP8 frame
+
+The VP8 bitstream format specification is described in [VP8 Data Format and
+Decoding Guide][rfc 6386]. Note that the VP8 frame header contains the VP8 frame
 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
+The VP8 specification describes how to decode the image into Y'CbCr format. To
-format. To convert to RGB, Rec. 601 SHOULD be used.
+convert to RGB, [Recommendation BT.601][rec601] SHOULD be used. Applications MAY
+use another conversion method, but visual results may differ among decoders.
 
 
 Simple File Format (Lossless)
 -----------------------------
 
-**Note:** Older readers may not support files using the lossless format.
+**Note**: Older readers may not support files using the lossless format.
 
 This layout SHOULD be used if the image requires _lossless_ encoding (with an
 optional transparency channel) and does not require advanced features provided
@@ -225,19 +231,22 @@ Simple WebP (lossless) file format:
      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    |                                                               |
     |                    WebP file header (12 bytes)                |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                          VP8L chunk                           |
+    :                         'VP8L' Chunk                          :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
-VP8L chunk:
+'VP8L' Chunk:
 
      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('VP8L')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                           VP8L data                           |
+    :                           VP8L data                           :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
 VP8L data: _Chunk Size_ bytes
@@ -253,23 +262,23 @@ and height of the canvas.
 Extended File Format
 --------------------
 
-**Note:** Older readers may not support files using the extended format.
+**Note**: Older readers may not support files using the extended format.
 
 An extended format file consists of:
 
-  * A 'VP8X' chunk with information about features used in the file.
+  * A 'VP8X' Chunk with information about features used in the file.
 
-  * An optional 'ICCP' chunk with color profile.
+  * An optional 'ICCP' Chunk with a color profile.
 
-  * An optional 'ANIM' chunk with animation control data.
+  * An optional 'ANIM' Chunk with animation control data.
 
   * 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 '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, which is made
 up of:
@@ -281,15 +290,18 @@ up of:
 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
+All chunks necessary for reconstruction and color correction, that is, 'VP8X',
-appears in the wrong place, the file is invalid, but readers MAY parse the
+'ICCP', 'ANIM', 'ANMF', 'ALPH', 'VP8 ', and 'VP8L', MUST appear in the order
-file, ignoring the chunks that come too late.
+described earlier. Readers SHOULD fail when chunks necessary for reconstruction
+and color correction are out of order.
 
-**Rationale:** Setting the order of chunks should allow quicker file
+[Metadata](#metadata) and [unknown chunks](#unknown-chunks) MAY appear out of
-parsing. For example, if an 'ALPH' chunk does not appear in its required
+order.
-position, a decoder can choose to stop searching for it. The rule of
+
-ignoring late chunks should make programs that need to do a full search
+**Rationale:** The chunks necessary for reconstruction should appear first in
-give the same results as the ones stopping early.
+the file to allow a reader to begin decoding an image before receiving all of
+the data. An application may benefit from varying the order of metadata and
+custom chunks to suit the implementation.
 
 Extended WebP file header:
 {:#extended_header}
@@ -297,9 +309,12 @@ Extended WebP file header:
      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+    |                                                               |
     |                   WebP file header (12 bytes)                 |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                      ChunkHeader('VP8X')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |Rsv|I|L|E|X|A|R|                   Reserved                    |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
@@ -310,20 +325,20 @@ Extended WebP file header:
 
 Reserved (Rsv): 2 bits
 
-: SHOULD be `0`.
+: MUST be `0`. Readers MUST ignore this field.
 
 ICC profile (I): 1 bit
 
-: Set if the file contains an ICC profile.
+: Set if the file contains an 'ICCP' Chunk.
 
 Alpha (L): 1 bit
 
 : Set if any of the frames of the image contain transparency information
   ("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
 
@@ -331,38 +346,38 @@ XMP metadata (X): 1 bit
 
 Animation (A): 1 bit
 
-: Set if this is an animated image. Data in 'ANIM' and 'ANMF' chunks should be
+: Set if this is an animated image. Data in 'ANIM' and 'ANMF' Chunks should be
   used to control the animation.
 
 Reserved (R): 1 bit
 
-: SHOULD be `0`.
+: MUST be `0`. Readers MUST ignore this field.
 
 Reserved: 24 bits
 
-: SHOULD be `0`.
+: MUST be `0`. Readers MUST ignore this field.
 
 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`.
 
-Future specifications MAY add more fields.
+Future specifications may add more fields. Unknown fields MUST be ignored.
 
 ### Chunks
 
 #### Animation
 
-An animation is controlled by ANIM and ANMF chunks.
+An animation is controlled by 'ANIM' and 'ANMF' Chunks.
 
-ANIM Chunk:
+'ANIM' Chunk:
 {:#anim_chunk}
 
 For an animated image, this chunk contains the _global parameters_ of the
@@ -372,6 +387,7 @@ animation.
      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('ANIM')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                       Background Color                        |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
@@ -383,14 +399,14 @@ 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`.
+  The background color is also used when the Disposal method is `1`.
 
-**Note**:
+**Notes**:
 
-  * Background color MAY contain a transparency value (alpha), even if the
+  * The background color MAY contain a non-opaque alpha value, even if the
-    _Alpha_ flag in [VP8X chunk](#extended_header) is unset.
+    _Alpha_ flag in the ['VP8X' Chunk](#extended_header) is unset.
 
-  * Viewer applications SHOULD treat the background color value as a hint, and
+  * 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
@@ -398,13 +414,14 @@ Background Color: 32 bits (_uint32_)
 
 Loop Count: 16 bits (_uint16_)
 
-: The number of times to loop the animation. `0` means infinitely.
+: The number of times to loop the animation. If it is `0`, this means
+  infinitely.
 
-This chunk MUST appear if the _Animation_ flag in the VP8X chunk is set.
+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
+If the _Animation_ flag is not set and this chunk is present, it MUST be
-SHOULD be ignored.
+ignored.
 
-ANMF chunk:
+'ANMF' Chunk:
 
 For animated images, this chunk contains information about a _single_ frame.
 If the _Animation flag_ is not set, then this chunk SHOULD NOT be present.
@@ -413,6 +430,7 @@ If the _Animation flag_ is not set, then this chunk SHOULD NOT be present.
      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('ANMF')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                        Frame X                |             ...
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
@@ -422,47 +440,47 @@ If the _Animation flag_ is not set, then this chunk SHOULD NOT be present.
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                 Frame Duration                |  Reserved |B|D|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                         Frame Data                            |
+    :                         Frame Data                            :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
 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.
+: The time to wait before displaying the next frame, in 1-millisecond units.
-  Note the interpretation of frame duration of 0 (and often <= 10) is
+  Note that the interpretation of the Frame Duration of 0 (and often <= 10) is
-  implementation defined. Many tools and browsers assign a minimum duration
+  defined by the implementation. Many tools and browsers assign a minimum
-  similar to GIF.
+  duration similar to GIF.
 
 Reserved: 6 bits
 
-: SHOULD be 0.
+: MUST be `0`. Readers MUST ignore this field.
 
 Blending method (B): 1 bit
 
 : 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
+    * `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
+      the current frame does not have an alpha channel, assume the alpha value
-      255, effectively replacing the rectangle.
+      is 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
@@ -475,20 +493,20 @@ Disposal method (D): 1 bit
 
     * `0`: Do not dispose. Leave the canvas as is.
 
-    * `1`: Dispose to background color. Fill the _rectangle_ on the canvas
+    * `1`: Dispose to the background color. Fill the _rectangle_ on the canvas
-      covered by the _current frame_ with background color specified in the
+      covered by the _current frame_ with the background color specified in the
-      [ANIM chunk](#anim_chunk).
+      ['ANIM' Chunk](#anim_chunk).
 
 **Notes**:
 
   * The frame disposal only applies to the _frame rectangle_, that is, the
-    rectangle defined by _Frame X_, _Frame Y_, _frame width_ and _frame height_.
+    rectangle defined by _Frame X_, _Frame Y_, _frame width_, and _frame
-    It may or may not cover the whole canvas.
+    height_. It may or may not cover the whole canvas.
 
 {:#alpha-blending}
-  * **Alpha-blending**:
+  * Alpha-blending:
 
-    Given that each of the R, G, B and A channels is 8-bit, and the RGB
+    Given that each of the R, G, B, and A channels is 8 bits, and the RGB
     channels are _not premultiplied_ by alpha, the formula for blending
     'dst' onto 'src' is:
 
@@ -497,16 +515,17 @@ Disposal method (D): 1 bit
     if blend.A = 0 then
       blend.RGB = 0
     else
-      blend.RGB = (src.RGB * src.A +
+      blend.RGB =
-                   dst.RGB * dst.A * (1 - src.A / 255)) / blend.A
+          (src.RGB * src.A +
+           dst.RGB * dst.A * (1 - src.A / 255)) / blend.A
 ~~~~~
 
   * Alpha-blending SHOULD be done in linear color space, by taking into account
     the [color profile](#color-profile) of the image. If the color profile is
-    not present, sRGB is to be assumed. (Note that sRGB also needs to be
+    not present, standard RGB (sRGB) is to be assumed. (Note that sRGB also
-    linearized due to a gamma of ~2.2).
+    needs to be linearized due to a gamma of ~2.2.)
 
-Frame Data: _Chunk Size_ - `16` bytes
+Frame Data: _Chunk Size_ bytes - `16`
 
 : Consists of:
 
@@ -516,8 +535,8 @@ Frame Data: _Chunk Size_ - `16` bytes
 
   * An optional list of [unknown chunks](#unknown-chunks).
 
-**Note**: The 'ANMF' payload, _Frame Data_ above, consists of individual
+**Note**: The 'ANMF' payload, _Frame Data_, consists of individual
-_padded_ chunks as described by the [RIFF file format](#riff-file-format).
+_padded_ chunks, as described by the [RIFF file format](#riff-file-format).
 
 #### Alpha
 
@@ -525,26 +544,29 @@ _padded_ chunks as described by the [RIFF file format](#riff-file-format).
      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('ALPH')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |Rsv| P | F | C |     Alpha Bitstream...                        |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
 Reserved (Rsv): 2 bits
 
-: SHOULD be `0`.
+: MUST be `0`. Readers MUST ignore this field.
 
-Pre-processing (P): 2 bits
+Preprocessing (P): 2 bits
 
-: These INFORMATIVE bits are used to signal the pre-processing that has
+: These _informative_ bits are used to signal the preprocessing 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.
+  for example, dither the values or smooth the gradients prior to display.
 
-    * `0`: no pre-processing
+    * `0`: No preprocessing.
-    * `1`: level reduction
+    * `1`: Level reduction.
+
+Decoders are not required to use this information in any specified way.
 
 Filtering method (F): 2 bits
 
-: The filtering method used:
+: The filtering methods used are described as follows:
 
     * `0`: None.
     * `1`: Horizontal filter.
@@ -568,27 +590,25 @@ made depending on the filtering method:
 
 where `clip(v)` is equal to:
 
-  * 0    if v < 0
+  * 0    if v < 0,
-  * 255  if v > 255
+  * 255  if v > 255, or
   * v    otherwise
 
 The final value is derived by adding the decompressed value `X` to the
-predictor and using modulo-256 arithmetic to wrap the \[256-511\] range
+predictor and using modulo-256 arithmetic to wrap the \[256..511\] range
-into the \[0-255\] one:
+into the \[0..255\] one:
 
 `alpha = (predictor + X) % 256`
 
-There are special cases for left-most and top-most pixel positions:
+There are special cases for the left-most and top-most pixel positions. For
+example, the top-left value at location (0, 0) uses 0 as the predictor value.
+Otherwise:
 
-  * Top-left value at location (0,0) uses 0 as predictor value. Otherwise,
   * For horizontal or gradient filtering methods, the left-most pixels at
     location (0, y) are predicted using the location (0, y-1) just above.
   * For vertical or gradient filtering methods, the top-most pixels at
     location (x, 0) are predicted using the location (x-1, 0) on the left.
 
-
-Decoders are not required to use this information in any specified way.
-
 Compression method (C): 2 bits
 
 : The compression method used:
@@ -596,37 +616,37 @@ Compression method (C): 2 bits
     * `0`: No compression.
     * `1`: Compressed using the WebP lossless format.
 
-Alpha bitstream: _Chunk Size_ - `1` bytes
+Alpha bitstream: _Chunk Size_ bytes - `1`
 
 : Encoded alpha bitstream.
 
 This optional chunk contains encoded alpha data for this frame. A frame
-containing a 'VP8L' chunk SHOULD NOT contain this chunk.
+containing a 'VP8L' Chunk SHOULD NOT contain this chunk.
 
 **Rationale**: The transparency information is already part of the 'VP8L'
-chunk.
+Chunk.
 
-The alpha channel data is stored as uncompressed raw data (when
+The alpha channel data is stored as uncompressed raw data (when the
 compression method is '0') or compressed using the lossless format
 (when the compression method is '1').
 
-  * Raw data: consists of a byte sequence of length width * height,
+  * Raw data: This consists of a byte sequence of length = width * height,
     containing all the 8-bit transparency values in scan order.
 
-  * Lossless format compression: the byte sequence is a compressed
+  * Lossless format compression: The byte sequence is a compressed
-    image-stream (as described in the [WebP Lossless Bitstream Format]
+    image-stream (as described in ["WebP Lossless Bitstream Format"]
-    [webpllspec]) of implicit dimension width x height. That is, this
+    [webpllspec]) of implicit dimensions width x height. That is, this
-    image-stream does NOT contain any headers describing the image dimension.
+    image-stream does NOT contain any headers describing the image dimensions.
 
-    **Rationale**: the dimension is already known from other sources,
+    **Rationale**: The dimensions are already known from other sources,
-    so storing it again would be redundant and error-prone.
+    so storing them again would be redundant and prone to error.
 
-    Once the image-stream is decoded into ARGB color values, following
+    Once the image-stream is decoded into Alpha, Red, Green, Blue (ARGB) color
-    the process described in the lossless format specification, the
+    values, following the process described in the lossless format
-    transparency information must be extracted from the *green* channel
+    specification, the transparency information must be extracted from the
-    of the ARGB quadruplet.
+    *green* channel of the ARGB quadruplet.
 
-    **Rationale**: the green channel is allowed extra transformation
+    **Rationale**: The green channel is allowed extra transformation
     steps in the specification -- unlike the other channels -- that can
     improve compression.
 
@@ -634,22 +654,23 @@ compression method is '0') or compressed using the lossless format
 
 This chunk contains compressed bitstream data for a single frame.
 
-A bitstream chunk may be either (i) a VP8 chunk, using "VP8 " (note the
+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
+significant fourth-character space) as its FourCC, _or_ (ii) a 'VP8L' Chunk,
-"VP8L" as its tag.
+using 'VP8L' as its FourCC.
 
-The formats of VP8 and VP8L chunks are as described in sections
+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.
+and [Simple File Format (Lossless)](#simple-file-format-lossless), respectively.
 
-#### Color profile
+#### Color Profile
 
      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('ICCP')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                       Color Profile                           |
+    :                       Color Profile                           :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
 Color Profile: _Chunk Size_ bytes
@@ -666,114 +687,145 @@ If this chunk is not present, sRGB SHOULD be assumed.
 
 #### Metadata
 
-Metadata can be stored in 'EXIF' or 'XMP ' chunks.
+Metadata can be stored in 'EXIF' or 'XMP ' Chunks.
 
 There SHOULD be at most one chunk of each type ('EXIF' and 'XMP '). If there
-are more such chunks, readers MAY ignore all except the first one. Also, a file
+are more such chunks, readers MAY ignore all except the first one.
-may possibly contain both 'EXIF' and 'XMP ' chunks.
 
 The chunks are defined as follows:
 
-EXIF chunk:
+'EXIF' Chunk:
 
      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('EXIF')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                        EXIF Metadata                          |
+    :                        Exif Metadata                          :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
-EXIF Metadata: _Chunk Size_ bytes
+Exif Metadata: _Chunk Size_ bytes
 
-: image metadata in EXIF format.
+: Image metadata in Exif format.
 
-XMP chunk:
+'XMP ' Chunk:
 
      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('XMP ')                      |
+    |                                                               |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    |                        XMP Metadata                           |
+    :                        XMP Metadata                           :
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 
 XMP Metadata: _Chunk Size_ bytes
 
-: image metadata in XMP format.
+: Image metadata in XMP format.
+
+Note that the fourth character in the 'XMP ' FourCC is an ASCII space (0x20).
 
 Additional guidance about handling metadata can be found in the
-Metadata Working Group's [Guidelines for Handling Metadata][metadata].
+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
+A RIFF chunk (described in the [RIFF File Format](#riff-file-format) section)
-tag_ is different from any of the chunks described in this document, is
+whose FourCC is different from any of the chunks described in this document, is
 considered an _unknown chunk_.
 
 **Rationale**: Allowing unknown chunks gives a provision for future extension
-of the format, and also allows storage of any application-specific data.
+of the format and also allows storage of any application-specific data.
 
 A file MAY contain unknown chunks:
 
-  * At the end of the file as described in [Extended WebP file
+  * at the end of the file, as described in [Extended WebP file
-    header](#extended_header) section.
+    header](#extended_header) section, or
-  * At the end of ANMF chunks as described in the
+  * 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 frames
+### Canvas Assembly from Frames
 
-Here we provide an overview of how a reader should assemble a canvas in the
+Here we provide an overview of how a reader MUST assemble a canvas in the case
-case of an animated image. The notation _VP8X.field_ means the field in the
+of an animated image.
-'VP8X' chunk with the same description.
 
-Displaying an _animated image_ canvas MUST be equivalent to the following
+The process begins with creating a canvas using the dimensions given in the
-pseudocode:
+'VP8X' Chunk, `Canvas Width Minus One + 1` pixels wide by `Canvas Height Minus
+One + 1` pixels high. The `Loop Count` field from the 'ANIM' Chunk controls how
+many times the animation process is repeated. This is `Loop Count - 1` for
+nonzero `Loop Count` values or infinite if the `Loop Count` is zero.
+
+At the beginning of each loop iteration, the canvas is filled using the
+background color from the 'ANIM' Chunk or an application-defined color.
+
+'ANMF' Chunks contain individual frames given in display order. Before rendering
+each frame, the previous frame's `Disposal method` is applied.
+
+The rendering of the decoded frame begins at the Cartesian coordinates (`2 *
+Frame X`, `2 * Frame Y`), using the top-left corner of the canvas as the origin.
+`Frame Width Minus One + 1` pixels wide by `Frame Height Minus One + 1` pixels
+high are rendered onto the canvas using the `Blending method`.
+
+The canvas is displayed for `Frame Duration` milliseconds. This continues until
+all frames given by 'ANMF' Chunks have been displayed. A new loop iteration is
+then begun, or the canvas is left in its final state if all iterations have been
+completed.
+
+The following pseudocode illustrates the rendering process. The notation
+_VP8X.field_ means the field in the 'VP8X' Chunk with the same description.
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-assert VP8X.flags.hasAnimation
+VP8X.flags.hasAnimation MUST be TRUE
 canvas ← new image of size VP8X.canvasWidth x VP8X.canvasHeight with
-         background color ANIM.background_color.
+         background color ANIM.background_color or
+         application-defined color.
 loop_count ← ANIM.loopCount
-dispose_method ← ANIM.disposeMethod
+dispose_method ← Dispose to background color
 if loop_count == 0:
-    loop_count = ∞
+  loop_count = ∞
 frame_params ← nil
-assert next chunk in image_data is ANMF
+next chunk in image_data is ANMF MUST be TRUE
 for loop = 0..loop_count - 1
-    clear canvas to ANIM.background_color or application defined color
+  clear canvas to ANIM.background_color or application-defined color
-    until eof or non-ANMF chunk
+  until eof or non-ANMF chunk
-        frame_params.frameX = Frame X
+    frame_params.frameX = Frame X
-        frame_params.frameY = Frame Y
+    frame_params.frameY = Frame Y
-        frame_params.frameWidth = Frame Width Minus One + 1
+    frame_params.frameWidth = Frame Width Minus One + 1
-        frame_params.frameHeight = Frame Height Minus One + 1
+    frame_params.frameHeight = Frame Height Minus One + 1
-        frame_params.frameDuration = Frame Duration
+    frame_params.frameDuration = Frame Duration
-        frame_right = frame_params.frameX + frame_params.frameWidth
+    frame_right = frame_params.frameX + frame_params.frameWidth
-        frame_bottom = frame_params.frameY + frame_params.frameHeight
+    frame_bottom = frame_params.frameY + frame_params.frameHeight
-        assert VP8X.canvasWidth >= frame_right
+    VP8X.canvasWidth >= frame_right MUST be TRUE
-        assert VP8X.canvasHeight >= frame_bottom
+    VP8X.canvasHeight >= frame_bottom MUST be TRUE
-        for subchunk in 'Frame Data':
+    for subchunk in 'Frame Data':
-            if subchunk.tag == "ALPH":
+      if subchunk.tag == "ALPH":
-                assert alpha subchunks not found in 'Frame Data' earlier
+        alpha subchunks not found in 'Frame Data' earlier MUST be
-                frame_params.alpha = alpha_data
+          TRUE
-            else if subchunk.tag == "VP8 " OR subchunk.tag == "VP8L":
+        frame_params.alpha = alpha_data
-                assert bitstream subchunks not found in 'Frame Data' earlier
+      else if subchunk.tag == "VP8 " OR subchunk.tag == "VP8L":
-                frame_params.bitstream = bitstream_data
+        bitstream subchunks not found in 'Frame Data' earlier MUST
-        render frame with frame_params.alpha and frame_params.bitstream on
+          be TRUE
-            canvas with top-left corner at (frame_params.frameX,
+        frame_params.bitstream = bitstream_data
-            frame_params.frameY), using dispose method dispose_method.
+    apply dispose_method.
-        canvas contains the decoded image.
+    render frame with frame_params.alpha and frame_params.bitstream
-        Show the contents of the canvas for frame_params.frameDuration * 1ms.
+      on canvas with top-left corner at (frame_params.frameX,
+      frame_params.frameY), using Blending method
+      frame_params.blendingMethod.
+    canvas contains the decoded image.
+    Show the contents of the canvas for
+    frame_params.frameDuration * 1 ms.
+    dispose_method = frame_params.disposeMethod
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 
 Example File Layouts
 --------------------
 
-A lossy encoded image with alpha may look as follows:
+A lossy-encoded image with alpha may look as follows:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 RIFF/WEBP
@@ -782,16 +834,16 @@ RIFF/WEBP
 +- VP8 (bitstream)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-A losslessly encoded image may look as follows:
+A lossless-encoded image may look as follows:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 RIFF/WEBP
 +- VP8X (descriptions of features used)
-+- XYZW (unknown chunk)
 +- VP8L (lossless bitstream)
++- XYZW (unknown chunk)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-A lossless image with ICC profile and XMP metadata may
+A lossless image with an ICC profile and XMP metadata may
 look as follows:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -802,7 +854,7 @@ RIFF/WEBP
 +- XMP  (metadata)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-An animated image with EXIF metadata may look as follows:
+An animated image with Exif metadata may look as follows:
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 RIFF/WEBP
@@ -815,9 +867,11 @@ RIFF/WEBP
 +- EXIF (metadata)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-[vp8spec]:  http://tools.ietf.org/html/rfc6386
+[webpllspec]: https://chromium.googlesource.com/webm/libwebp/+/HEAD/doc/webp-lossless-bitstream-spec.txt
-[webpllspec]: https://chromium.googlesource.com/webm/libwebp/+/master/doc/webp-lossless-bitstream-spec.txt
+[iccspec]: https://www.color.org/icc_specs2.xalter
-[iccspec]: http://www.color.org/icc_specs2.xalter
+[metadata]: https://web.archive.org/web/20180919181934/http://www.metadataworkinggroup.org/pdf/mwg_guidance.pdf
-[metadata]: http://www.metadataworkinggroup.org/pdf/mwg_guidance.pdf
+[rec601]: https://www.itu.int/rec/R-REC-BT.601
-[rfc 1166]: http://tools.ietf.org/html/rfc1166
+[rfc 1166]: https://datatracker.ietf.org/doc/html/rfc1166
-[rfc 2119]: http://tools.ietf.org/html/rfc2119
+[rfc 2119]: https://datatracker.ietf.org/doc/html/rfc2119
+[rfc 6386]: https://datatracker.ietf.org/doc/html/rfc6386
+[rfc 8174]: https://datatracker.ietf.org/doc/html/rfc8174

examples/Android.mk

@@ -1,3 +1,5 @@
+# Ignore this file during non-NDK builds.
+ifdef NDK_ROOT
 LOCAL_PATH := $(call my-dir)
 
 ################################################################################
@@ -26,7 +28,6 @@ LOCAL_SRC_FILES := \
     cwebp.c \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
 LOCAL_STATIC_LIBRARIES := example_util imageio_util imagedec webpdemux webp
 
 LOCAL_MODULE := cwebp
@@ -42,7 +43,6 @@ LOCAL_SRC_FILES := \
     dwebp.c \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
 LOCAL_STATIC_LIBRARIES := example_util imagedec imageenc webpdemux webp
 LOCAL_MODULE := dwebp
 
@@ -57,7 +57,6 @@ LOCAL_SRC_FILES := \
     webpmux.c \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
 LOCAL_STATIC_LIBRARIES := example_util imageio_util webpmux webp
 
 LOCAL_MODULE := webpmux_example
@@ -73,7 +72,6 @@ LOCAL_SRC_FILES := \
     img2webp.c \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
 LOCAL_STATIC_LIBRARIES := example_util imageio_util imagedec webpmux webpdemux \
                           webp
 
@@ -90,9 +88,9 @@ LOCAL_SRC_FILES := \
     webpinfo.c \
 
 LOCAL_CFLAGS := $(WEBP_CFLAGS)
-LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
 LOCAL_STATIC_LIBRARIES := example_util imageio_util webp
 
 LOCAL_MODULE := webpinfo_example
 
 include $(BUILD_EXECUTABLE)
+endif  # NDK_ROOT

examples/Makefile.am

@@ -1,7 +1,7 @@
 AM_CPPFLAGS += -I$(top_builddir)/src -I$(top_srcdir)/src
 
 bin_PROGRAMS =
-if WANT_DEMUX
+if BUILD_DEMUX
   bin_PROGRAMS += dwebp cwebp
 endif
 if BUILD_ANIMDIFF
@@ -13,7 +13,7 @@ endif
 if BUILD_IMG2WEBP
   bin_PROGRAMS += img2webp
 endif
-if WANT_MUX
+if BUILD_MUX
   bin_PROGRAMS += webpmux
 endif
 if BUILD_VWEBP
@@ -28,7 +28,7 @@ noinst_LTLIBRARIES = libexample_util.la
 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
+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
@@ -36,7 +36,7 @@ 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
+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  =
@@ -47,7 +47,7 @@ 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_CPPFLAGS  = $(AM_CPPFLAGS) -I$(top_srcdir)
 cwebp_LDADD  =
 cwebp_LDADD += libexample_util.la
 cwebp_LDADD += ../imageio/libimageio_util.la
@@ -92,7 +92,7 @@ webpmux_LDADD += ../src/mux/libwebpmux.la
 webpmux_LDADD += ../src/libwebp.la
 
 img2webp_SOURCES = img2webp.c
-img2webp_CPPFLAGS = $(AM_CPPFLAGS)
+img2webp_CPPFLAGS = $(AM_CPPFLAGS) -I$(top_srcdir)
 img2webp_LDADD  =
 img2webp_LDADD += libexample_util.la
 img2webp_LDADD += ../imageio/libimageio_util.la

examples/anim_diff.c

@@ -16,10 +16,12 @@
 #include <assert.h>
 #include <limits.h>
 #include <stdio.h>
-#include <stdlib.h>  // for 'strtod'.
+#include <stdlib.h>
 #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
@@ -143,8 +145,18 @@ static int CompareAnimatedImagePair(const AnimatedImage* const img1,
   if (!ok) return 0;  // These are fatal failures, can't proceed.
 
   if (is_multi_frame_image) {  // Checks relevant for multi-frame images only.
-    ok = CompareValues(img1->loop_count, img2->loop_count,
+    int max_loop_count_workaround = 0;
-                       "Loop count mismatch") && ok;
+    // 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;
   }
@@ -194,8 +206,9 @@ static void Help(void) {
   printf("  -version ............ print version number and exit\n");
 }
 
+// Returns 0 on success, 1 if animation files differ, and 2 for any error.
 int main(int argc, const char* argv[]) {
-  int return_code = -1;
+  int return_code = 2;
   int dump_frames = 0;
   const char* dump_folder = NULL;
   double min_psnr = 0.;
@@ -207,25 +220,20 @@ int main(int argc, const char* argv[]) {
   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 = argv[++c];
+        dump_folder = (const char*)GET_WARGV(argv, ++c);
       } else {
         parse_error = 1;
       }
     } else if (!strcmp(argv[c], "-min_psnr")) {
       if (c < argc - 1) {
-        const char* const v = argv[++c];
+        min_psnr = ExUtilGetFloat(argv[++c], &parse_error);
-        char* end = NULL;
-        const double d = strtod(v, &end);
-        if (end == v) {
-          parse_error = 1;
-          fprintf(stderr, "Error! '%s' is not a floating point number.\n", v);
-        }
-        min_psnr = d;
       } else {
         parse_error = 1;
       }
@@ -233,20 +241,13 @@ int main(int argc, const char* argv[]) {
       premultiply = 0;
     } else if (!strcmp(argv[c], "-max_diff")) {
       if (c < argc - 1) {
-        const char* const v = argv[++c];
+        max_diff = ExUtilGetInt(argv[++c], 0, &parse_error);
-        char* end = NULL;
-        const int n = (int)strtol(v, &end, 10);
-        if (end == v) {
-          parse_error = 1;
-          fprintf(stderr, "Error! '%s' is not an integer.\n", v);
-        }
-        max_diff = n;
       } else {
         parse_error = 1;
       }
     } else if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
       Help();
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else if (!strcmp(argv[c], "-version")) {
       int dec_version, demux_version;
       GetAnimatedImageVersions(&dec_version, &demux_version);
@@ -255,13 +256,13 @@ int main(int argc, const char* argv[]) {
              (dec_version >> 0) & 0xff,
              (demux_version >> 16) & 0xff, (demux_version >> 8) & 0xff,
              (demux_version >> 0) & 0xff);
-      return 0;
+      FREE_WARGV_AND_RETURN(0);
     } else {
       if (!got_input1) {
-        files[0] = argv[c];
+        files[0] = (const char*)GET_WARGV(argv, c);
         got_input1 = 1;
       } else if (!got_input2) {
-        files[1] = argv[c];
+        files[1] = (const char*)GET_WARGV(argv, c);
         got_input2 = 1;
       } else {
         parse_error = 1;
@@ -269,30 +270,31 @@ int main(int argc, const char* argv[]) {
     }
     if (parse_error) {
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(return_code);
     }
   }
   if (argc < 3) {
     Help();
-    return -1;
+    FREE_WARGV_AND_RETURN(return_code);
   }
 
 
   if (!got_input2) {
     Help();
-    return -1;
+    FREE_WARGV_AND_RETURN(return_code);
   }
 
   if (dump_frames) {
-    printf("Dumping decoded frames in: %s\n", dump_folder);
+    WPRINTF("Dumping decoded frames in: %s\n", (const W_CHAR*)dump_folder);
   }
 
   memset(images, 0, sizeof(images));
   for (i = 0; i < 2; ++i) {
-    printf("Decoding file: %s\n", files[i]);
+    WPRINTF("Decoding file: %s\n", (const W_CHAR*)files[i]);
     if (!ReadAnimatedImage(files[i], &images[i], dump_frames, dump_folder)) {
-      fprintf(stderr, "Error decoding file: %s\n Aborting.\n", files[i]);
+      WFPRINTF(stderr, "Error decoding file: %s\n Aborting.\n",
-      return_code = -2;
+               (const W_CHAR*)files[i]);
+      return_code = 2;
       goto End;
     } else {
       MinimizeAnimationFrames(&images[i], max_diff);
@@ -301,14 +303,16 @@ int main(int argc, const char* argv[]) {
 
   if (!CompareAnimatedImagePair(&images[0], &images[1],
                                 premultiply, min_psnr)) {
-    fprintf(stderr, "\nFiles %s and %s differ.\n", files[0], files[1]);
+    WFPRINTF(stderr, "\nFiles %s and %s differ.\n", (const W_CHAR*)files[0],
-    return_code = -3;
+             (const W_CHAR*)files[1]);
+    return_code = 1;
   } else {
-    printf("\nFiles %s and %s are identical.\n", files[0], files[1]);
+    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]);
-  return return_code;
+  FREE_WARGV_AND_RETURN(return_code);
 }

examples/anim_dump.c

@@ -12,11 +12,13 @@
 // Author: Skal (pascal.massimino@gmail.com)
 
 #include <stdio.h>
+#include <stdlib.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
@@ -34,17 +36,20 @@ static void Help(void) {
   printf("  -version ............ print version number and exit\n");
 }
 
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
 int main(int argc, const char* argv[]) {
   int error = 0;
-  const char* dump_folder = ".";
+  const W_CHAR* dump_folder = TO_W_CHAR(".");
-  const char* prefix = "dump_";
+  const W_CHAR* prefix = TO_W_CHAR("dump_");
-  const char* suffix = "png";
+  const W_CHAR* suffix = TO_W_CHAR("png");
   WebPOutputFileFormat format = PNG;
   int c;
 
+  INIT_WARGV(argc, argv);
+
   if (argc < 2) {
     Help();
-    return -1;
+    FREE_WARGV_AND_RETURN(EXIT_FAILURE);
   }
 
   for (c = 1; !error && c < argc; ++c) {
@@ -54,23 +59,23 @@ int main(int argc, const char* argv[]) {
         error = 1;
         break;
       }
-      dump_folder = argv[++c];
+      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 = argv[++c];
+      prefix = GET_WARGV(argv, ++c);
     } else if (!strcmp(argv[c], "-tiff")) {
       format = TIFF;
-      suffix = "tiff";
+      suffix = TO_W_CHAR("tiff");
     } else if (!strcmp(argv[c], "-pam")) {
       format = PAM;
-      suffix = "pam";
+      suffix = TO_W_CHAR("pam");
     } else if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
       Help();
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else if (!strcmp(argv[c], "-version")) {
       int dec_version, demux_version;
       GetAnimatedImageVersions(&dec_version, &demux_version);
@@ -79,23 +84,27 @@ int main(int argc, const char* argv[]) {
              (dec_version >> 0) & 0xff,
              (demux_version >> 16) & 0xff, (demux_version >> 8) & 0xff,
              (demux_version >> 0) & 0xff);
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else {
       uint32_t i;
       AnimatedImage image;
-      const char* const file = argv[c];
+      const W_CHAR* const file = GET_WARGV(argv, c);
       memset(&image, 0, sizeof(image));
-      printf("Decoding file: %s as %s/%sxxxx.%s\n",
+      WPRINTF("Decoding file: %s as %s/%sxxxx.%s\n",
-             file, dump_folder, prefix, suffix);
+              file, dump_folder, prefix, suffix);
-      if (!ReadAnimatedImage(file, &image, 0, NULL)) {
+      if (!ReadAnimatedImage((const char*)file, &image, 0, NULL)) {
-        fprintf(stderr, "Error decoding file: %s\n Aborting.\n", file);
+        WFPRINTF(stderr, "Error decoding file: %s\n Aborting.\n", file);
         error = 1;
         break;
       }
       for (i = 0; !error && i < image.num_frames; ++i) {
-        char out_file[1024];
+        W_CHAR out_file[1024];
         WebPDecBuffer buffer;
-        WebPInitDecBuffer(&buffer);
+        if (!WebPInitDecBuffer(&buffer)) {
+          fprintf(stderr, "Cannot init dec buffer\n");
+          error = 1;
+          continue;
+        }
         buffer.colorspace = MODE_RGBA;
         buffer.is_external_memory = 1;
         buffer.width = image.canvas_width;
@@ -103,10 +112,10 @@ int main(int argc, const char* argv[]) {
         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;
-        snprintf(out_file, sizeof(out_file), "%s/%s%.4d.%s",
+        WSNPRINTF(out_file, sizeof(out_file), "%s/%s%.4d.%s",
-                 dump_folder, prefix, i, suffix);
+                  dump_folder, prefix, i, suffix);
-        if (!WebPSaveImage(&buffer, format, out_file)) {
+        if (!WebPSaveImage(&buffer, format, (const char*)out_file)) {
-          fprintf(stderr, "Error while saving image '%s'\n", out_file);
+          WFPRINTF(stderr, "Error while saving image '%s'\n", out_file);
           error = 1;
         }
         WebPFreeDecBuffer(&buffer);
@@ -114,5 +123,5 @@ int main(int argc, const char* argv[]) {
       ClearAnimatedImage(&image);
     }
   }
-  return error ? 1 : 0;
+  FREE_WARGV_AND_RETURN(error ? EXIT_FAILURE : EXIT_SUCCESS);
 }

examples/anim_util.c

@@ -23,6 +23,9 @@
 #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
@@ -57,15 +60,15 @@ static int AllocateFrames(AnimatedImage* const image, uint32_t num_frames) {
       !CheckSizeForOverflow(total_frame_size)) {
     return 0;
   }
-  mem = (uint8_t*)malloc((size_t)total_size);
+  mem = (uint8_t*)WebPMalloc((size_t)total_size);
-  frames = (DecodedFrame*)malloc((size_t)total_frame_size);
+  frames = (DecodedFrame*)WebPMalloc((size_t)total_frame_size);
 
   if (mem == NULL || frames == NULL) {
-    free(mem);
+    WebPFree(mem);
-    free(frames);
+    WebPFree(frames);
     return 0;
   }
-  free(image->raw_mem);
+  WebPFree(image->raw_mem);
   image->num_frames = num_frames;
   image->frames = frames;
   for (i = 0; i < num_frames; ++i) {
@@ -79,8 +82,8 @@ static int AllocateFrames(AnimatedImage* const image, uint32_t num_frames) {
 
 void ClearAnimatedImage(AnimatedImage* const image) {
   if (image != NULL) {
-    free(image->raw_mem);
+    WebPFree(image->raw_mem);
-    free(image->frames);
+    WebPFree(image->frames);
     image->num_frames = 0;
     image->frames = NULL;
     image->raw_mem = NULL;
@@ -151,42 +154,42 @@ static int DumpFrame(const char filename[], const char dump_folder[],
   int ok = 0;
   size_t max_len;
   int y;
-  const char* base_name = NULL;
+  const W_CHAR* base_name = NULL;
-  char* file_name = NULL;
+  W_CHAR* file_name = NULL;
   FILE* f = NULL;
   const char* row;
 
-  if (dump_folder == NULL) dump_folder = ".";
+  if (dump_folder == NULL) dump_folder = (const char*)TO_W_CHAR(".");
 
-  base_name = strrchr(filename, '/');
+  base_name = WSTRRCHR(filename, '/');
-  base_name = (base_name == NULL) ? filename : base_name + 1;
+  base_name = (base_name == NULL) ? (const W_CHAR*)filename : base_name + 1;
-  max_len = strlen(dump_folder) + 1 + strlen(base_name)
+  max_len = WSTRLEN(dump_folder) + 1 + WSTRLEN(base_name)
           + strlen("_frame_") + strlen(".pam") + 8;
-  file_name = (char*)malloc(max_len * sizeof(*file_name));
+  file_name = (W_CHAR*)WebPMalloc(max_len * sizeof(*file_name));
   if (file_name == NULL) goto End;
 
-  if (snprintf(file_name, max_len, "%s/%s_frame_%d.pam",
+  if (WSNPRINTF(file_name, max_len, "%s/%s_frame_%d.pam",
-               dump_folder, base_name, frame_num) < 0) {
+                (const W_CHAR*)dump_folder, base_name, frame_num) < 0) {
     fprintf(stderr, "Error while generating file name\n");
     goto End;
   }
 
-  f = fopen(file_name, "wb");
+  f = WFOPEN(file_name, "wb");
   if (f == NULL) {
-    fprintf(stderr, "Error opening file for writing: %s\n", file_name);
+    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) {
-    fprintf(stderr, "Write error for file %s\n", file_name);
+    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) {
-      fprintf(stderr, "Error writing to file: %s\n", file_name);
+      WFPRINTF(stderr, "Error writing to file: %s\n", file_name);
       goto End;
     }
     row += canvas_width * kNumChannels;
@@ -194,7 +197,7 @@ static int DumpFrame(const char filename[], const char dump_folder[],
   ok = 1;
  End:
   if (f != NULL) fclose(f);
-  free(file_name);
+  WebPFree(file_name);
   return ok;
 }
 
@@ -222,7 +225,7 @@ static int ReadAnimatedWebP(const char filename[],
 
   dec = WebPAnimDecoderNew(webp_data, NULL);
   if (dec == NULL) {
-    fprintf(stderr, "Error parsing image: %s\n", filename);
+    WFPRINTF(stderr, "Error parsing image: %s\n", (const W_CHAR*)filename);
     goto End;
   }
 
@@ -238,7 +241,7 @@ static int ReadAnimatedWebP(const char filename[],
   image->bgcolor = anim_info.bgcolor;
 
   // Allocate frames.
-  if (!AllocateFrames(image, anim_info.frame_count)) return 0;
+  if (!AllocateFrames(image, anim_info.frame_count)) goto End;
 
   // Decode frames.
   while (WebPAnimDecoderHasMoreFrames(dec)) {
@@ -275,6 +278,7 @@ static int ReadAnimatedWebP(const char filename[],
     prev_frame_timestamp = timestamp;
   }
   ok = dump_ok;
+  if (ok) image->format = ANIM_WEBP;
 
  End:
   WebPAnimDecoderDelete(dec);
@@ -369,26 +373,6 @@ static int DGifSavedExtensionToGCB(GifFileType* GifFile, int ImageIndex,
 #define DGifCloseFile(a, b) DGifCloseFile(a)
 #endif
 
-static 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)
-  const char* error_str =
-      GifErrorString((gif == NULL) ? gif_error : gif->Error);
-#else
-  const char* error_str = 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 int IsKeyFrameGIF(const GifImageDesc* prev_desc, int prev_dispose,
                          const DecodedFrame* const prev_frame,
                          int canvas_width, int canvas_height) {
@@ -421,7 +405,7 @@ static uint32_t GetBackgroundColorGIF(GifFileType* gif) {
     return 0xffffffff;  // Invalid: assume white.
   } else {
     const GifColorType color = color_map->Colors[gif->SBackGroundColor];
-    return (0xff << 24) |
+    return (0xffu << 24) |
            (color.Red << 16) |
            (color.Green << 8) |
            (color.Blue << 0);
@@ -529,15 +513,15 @@ static int ReadAnimatedGIF(const char filename[], AnimatedImage* const image,
   int gif_error;
   GifFileType* gif;
 
-  gif = DGifOpenFileName(filename, NULL);
+  gif = DGifOpenFileUnicode((const W_CHAR*)filename, NULL);
   if (gif == NULL) {
-    fprintf(stderr, "Could not read file: %s.\n", filename);
+    WFPRINTF(stderr, "Could not read file: %s.\n", (const W_CHAR*)filename);
     return 0;
   }
 
   gif_error = DGifSlurp(gif);
   if (gif_error != GIF_OK) {
-    fprintf(stderr, "Could not parse image: %s.\n", filename);
+    WFPRINTF(stderr, "Could not parse image: %s.\n", (const W_CHAR*)filename);
     GIFDisplayError(gif, gif_error);
     DGifCloseFile(gif, NULL);
     return 0;
@@ -574,7 +558,10 @@ static int ReadAnimatedGIF(const char filename[], AnimatedImage* const image,
     }
   }
   // Allocate frames.
-  AllocateFrames(image, frame_count);
+  if (!AllocateFrames(image, frame_count)) {
+    DGifCloseFile(gif, NULL);
+    return 0;
+  }
 
   canvas_width = image->canvas_width;
   canvas_height = image->canvas_height;
@@ -687,6 +674,7 @@ static int ReadAnimatedGIF(const char filename[], AnimatedImage* const image,
       }
     }
   }
+  image->format = ANIM_GIF;
   DGifCloseFile(gif, NULL);
   return 1;
 }
@@ -722,7 +710,7 @@ int ReadAnimatedImage(const char filename[], AnimatedImage* const image,
   memset(image, 0, sizeof(*image));
 
   if (!ImgIoUtilReadFile(filename, &webp_data.bytes, &webp_data.size)) {
-    fprintf(stderr, "Error reading file: %s\n", filename);
+    WFPRINTF(stderr, "Error reading file: %s\n", (const W_CHAR*)filename);
     return 0;
   }
 
@@ -732,9 +720,9 @@ int ReadAnimatedImage(const char filename[], AnimatedImage* const image,
   } else if (IsGIF(&webp_data)) {
     ok = ReadAnimatedGIF(filename, image, dump_frames, dump_folder);
   } else {
-    fprintf(stderr,
+    WFPRINTF(stderr,
-            "Unknown file type: %s. Supported file types are WebP and GIF\n",
+             "Unknown file type: %s. Supported file types are WebP and GIF\n",
-            filename);
+             (const W_CHAR*)filename);
     ok = 0;
   }
   if (!ok) ClearAnimatedImage(image);

examples/anim_util.h

@@ -22,6 +22,11 @@
 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.
@@ -29,6 +34,7 @@ typedef struct {
 } DecodedFrame;
 
 typedef struct {
+  AnimatedFileFormat format;
   uint32_t canvas_width;
   uint32_t canvas_height;
   uint32_t bgcolor;

examples/cwebp.c

@@ -12,6 +12,7 @@
 //
 // Author: Skal (pascal.massimino@gmail.com)
 
+#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -23,7 +24,10 @@
 #include "../examples/example_util.h"
 #include "../imageio/image_dec.h"
 #include "../imageio/imageio_util.h"
+#include "../imageio/webpdec.h"
 #include "./stopwatch.h"
+#include "./unicode.h"
+#include "sharpyuv/sharpyuv.h"
 #include "webp/encode.h"
 
 #ifndef WEBP_DLL
@@ -88,9 +92,10 @@ static int ReadPicture(const char* const filename, WebPPicture* const pic,
     }
   }
   if (!ok) {
-    fprintf(stderr, "Error! Could not process file %s\n", filename);
+    WFPRINTF(stderr, "Error! Could not process file %s\n",
+             (const W_CHAR*)filename);
   }
-  free((void*)data);
+  WebPFree((void*)data);
   return ok;
 }
 
@@ -114,9 +119,10 @@ static int ReadPicture(const char* const filename, WebPPicture* const pic,
   }
  End:
   if (!ok) {
-    fprintf(stderr, "Error! Could not process file %s\n", filename);
+    WFPRINTF(stderr, "Error! Could not process file %s\n",
+             (const W_CHAR*)filename);
   }
-  free((void*)data);
+  WebPFree((void*)data);
   return ok;
 }
 
@@ -125,7 +131,8 @@ static int ReadPicture(const char* const filename, WebPPicture* const pic,
 static void AllocExtraInfo(WebPPicture* const pic) {
   const int mb_w = (pic->width + 15) / 16;
   const int mb_h = (pic->height + 15) / 16;
-  pic->extra_info = (uint8_t*)malloc(mb_w * mb_h * sizeof(*pic->extra_info));
+  pic->extra_info =
+      (uint8_t*)WebPMalloc(mb_w * mb_h * sizeof(*pic->extra_info));
 }
 
 static void PrintByteCount(const int bytes[4], int total_size,
@@ -144,7 +151,7 @@ static void PrintPercents(const int counts[4]) {
   int s;
   const int total = counts[0] + counts[1] + counts[2] + counts[3];
   for (s = 0; s < 4; ++s) {
-    fprintf(stderr, "|      %2d%%", (int)(100. * counts[s] / total + .5));
+    fprintf(stderr, "|     %3d%%", (int)(100. * counts[s] / total + .5));
   }
   fprintf(stderr, "| %7d\n", total);
 }
@@ -171,8 +178,14 @@ static void PrintFullLosslessInfo(const WebPAuxStats* const stats,
     if (stats->lossless_features & 8) fprintf(stderr, " PALETTE");
     fprintf(stderr, "\n");
   }
-  fprintf(stderr, "  * Precision Bits: histogram=%d transform=%d cache=%d\n",
+  fprintf(stderr, "  * Precision Bits: histogram=%d", stats->histogram_bits);
-          stats->histogram_bits, stats->transform_bits, stats->cache_bits);
+  if (stats->lossless_features & 1) {
+    fprintf(stderr, " prediction=%d", stats->transform_bits);
+  }
+  if (stats->lossless_features & 2) {
+    fprintf(stderr, " cross-color=%d", stats->cross_color_transform_bits);
+  }
+  fprintf(stderr, " cache=%d\n", stats->cache_bits);
   if (stats->palette_size > 0) {
     fprintf(stderr, "  * Palette size:   %d\n", stats->palette_size);
   }
@@ -185,7 +198,7 @@ static void PrintExtraInfoLossless(const WebPPicture* const pic,
   if (short_output) {
     fprintf(stderr, "%7d %2.2f\n", stats->coded_size, stats->PSNR[3]);
   } else {
-    fprintf(stderr, "File:      %s\n", file_name);
+    WFPRINTF(stderr, "File:      %s\n", (const W_CHAR*)file_name);
     fprintf(stderr, "Dimension: %d x %d\n", pic->width, pic->height);
     fprintf(stderr, "Output:    %d bytes (%.2f bpp)\n", stats->coded_size,
             8.f * stats->coded_size / pic->width / pic->height);
@@ -204,7 +217,7 @@ static void PrintExtraInfoLossy(const WebPPicture* const pic, int short_output,
     const int num_i16 = stats->block_count[1];
     const int num_skip = stats->block_count[2];
     const int total = num_i4 + num_i16;
-    fprintf(stderr, "File:      %s\n", file_name);
+    WFPRINTF(stderr, "File:      %s\n", (const W_CHAR*)file_name);
     fprintf(stderr, "Dimension: %d x %d%s\n",
             pic->width, pic->height,
             stats->alpha_data_size ? " (with alpha)" : "");
@@ -299,6 +312,7 @@ static int MyWriter(const uint8_t* data, size_t data_size,
 // Dumps a picture as a PGM file using the IMC4 layout.
 static int DumpPicture(const WebPPicture* const picture, const char* PGM_name) {
   int y;
+  int ok = 0;
   const int uv_width = (picture->width + 1) / 2;
   const int uv_height = (picture->height + 1) / 2;
   const int stride = (picture->width + 1) & ~1;
@@ -309,27 +323,30 @@ static int DumpPicture(const WebPPicture* const picture, const char* PGM_name) {
   const int alpha_height =
       WebPPictureHasTransparency(picture) ? picture->height : 0;
   const int height = picture->height + uv_height + alpha_height;
-  FILE* const f = fopen(PGM_name, "wb");
+  FILE* const f = WFOPEN(PGM_name, "wb");
   if (f == NULL) return 0;
   fprintf(f, "P5\n%d %d\n255\n", stride, height);
   for (y = 0; y < picture->height; ++y) {
-    if (fwrite(src_y, picture->width, 1, f) != 1) return 0;
+    if (fwrite(src_y, picture->width, 1, f) != 1) goto Error;
     if (picture->width & 1) fputc(0, f);  // pad
     src_y += picture->y_stride;
   }
   for (y = 0; y < uv_height; ++y) {
-    if (fwrite(src_u, uv_width, 1, f) != 1) return 0;
+    if (fwrite(src_u, uv_width, 1, f) != 1) goto Error;
-    if (fwrite(src_v, uv_width, 1, f) != 1) return 0;
+    if (fwrite(src_v, uv_width, 1, f) != 1) goto Error;
     src_u += picture->uv_stride;
     src_v += picture->uv_stride;
   }
   for (y = 0; y < alpha_height; ++y) {
-    if (fwrite(src_a, picture->width, 1, f) != 1) return 0;
+    if (fwrite(src_a, picture->width, 1, f) != 1) goto Error;
     if (picture->width & 1) fputc(0, f);  // pad
     src_a += picture->a_stride;
   }
+  ok = 1;
+
+ Error:
   fclose(f);
-  return 1;
+  return ok;
 }
 
 // -----------------------------------------------------------------------------
@@ -521,6 +538,7 @@ static void HelpLong(void) {
   printf(" cwebp [-preset <...>] [options] in_file [-o out_file]\n\n");
   printf("If input size (-s) for an image is not specified, it is\n"
          "assumed to be a PNG, JPEG, TIFF or WebP file.\n");
+  printf("Note: Animated PNG and WebP files are not supported.\n");
 #ifdef HAVE_WINCODEC_H
   printf("Windows builds can take as input any of the files handled by WIC.\n");
 #endif
@@ -561,8 +579,10 @@ static void HelpLong(void) {
   printf("                           "
          "the first partition (0=no degradation ... 100=full)\n");
   printf("  -pass <int> ............ analysis pass number (1..10)\n");
+  printf("  -qrange <min> <max> .... specifies the permissible quality range\n"
+         "                           (default: 0 100)\n");
   printf("  -crop <x> <y> <w> <h> .. crop picture with the given rectangle\n");
-  printf("  -resize <w> <h> ........ resize picture (after any cropping)\n");
+  printf("  -resize <w> <h> ........ resize picture (*after* any cropping)\n");
   printf("  -mt .................... use multi-threading if available\n");
   printf("  -low_memory ............ reduce memory usage (slower encoding)\n");
   printf("  -map <int> ............. print map of extra info\n");
@@ -582,9 +602,8 @@ static void HelpLong(void) {
          "                           green=0xe0 and blue=0xd0\n");
   printf("  -noalpha ............... discard any transparency information\n");
   printf("  -lossless .............. encode image losslessly, default=off\n");
-  printf("  -near_lossless <int> ... use near-lossless image\n"
+  printf("  -near_lossless <int> ... use near-lossless image preprocessing\n"
-         "                           preprocessing (0..100=off), "
+         "                           (0..100=off), default=100\n");
-         "default=100\n");
   printf("  -hint <string> ......... specify image characteristics hint,\n");
   printf("                           one of: photo, picture or graph\n");
 
@@ -611,6 +630,7 @@ static void HelpLong(void) {
   printf("  -af .................... auto-adjust filter strength\n");
   printf("  -pre <int> ............. pre-processing filter\n");
   printf("\n");
+  printf("Supported input formats:\n  %s\n", WebPGetEnabledInputFileFormats());
 }
 
 //------------------------------------------------------------------------------
@@ -637,10 +657,11 @@ static const char* const kErrorMessages[VP8_ENC_ERROR_LAST] = {
 
 //------------------------------------------------------------------------------
 
-int main(int argc, const char *argv[]) {
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
-  int return_value = -1;
+int main(int argc, const char* argv[]) {
-  const char *in_file = NULL, *out_file = NULL, *dump_file = NULL;
+  int return_value = EXIT_FAILURE;
-  FILE *out = NULL;
+  const char* in_file = NULL, *out_file = NULL, *dump_file = NULL;
+  FILE* out = NULL;
   int c;
   int short_output = 0;
   int quiet = 0;
@@ -660,35 +681,38 @@ int main(int argc, const char *argv[]) {
   WebPConfig config;
   WebPAuxStats stats;
   WebPMemoryWriter memory_writer;
+  int use_memory_writer;
   Metadata metadata;
   Stopwatch stop_watch;
 
+  INIT_WARGV(argc, argv);
+
   MetadataInit(&metadata);
   WebPMemoryWriterInit(&memory_writer);
   if (!WebPPictureInit(&picture) ||
       !WebPPictureInit(&original_picture) ||
       !WebPConfigInit(&config)) {
     fprintf(stderr, "Error! Version mismatch!\n");
-    return -1;
+    FREE_WARGV_AND_RETURN(EXIT_FAILURE);
   }
 
   if (argc == 1) {
     HelpShort();
-    return 0;
+    FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
   }
 
   for (c = 1; c < argc; ++c) {
     int parse_error = 0;
     if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
       HelpShort();
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else if (!strcmp(argv[c], "-H") || !strcmp(argv[c], "-longhelp")) {
       HelpLong();
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
-    } else if (!strcmp(argv[c], "-o") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-o") && c + 1 < argc) {
-      out_file = argv[++c];
+      out_file = (const char*)GET_WARGV(argv, ++c);
-    } else if (!strcmp(argv[c], "-d") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-d") && c + 1 < argc) {
-      dump_file = argv[++c];
+      dump_file = (const char*)GET_WARGV(argv, ++c);
       config.show_compressed = 1;
     } else if (!strcmp(argv[c], "-print_psnr")) {
       config.show_compressed = 1;
@@ -701,7 +725,7 @@ int main(int argc, const char *argv[]) {
       print_distortion = 2;
     } else if (!strcmp(argv[c], "-short")) {
       ++short_output;
-    } else if (!strcmp(argv[c], "-s") && c < argc - 2) {
+    } else if (!strcmp(argv[c], "-s") && c + 2 < argc) {
       picture.width = ExUtilGetInt(argv[++c], 0, &parse_error);
       picture.height = ExUtilGetInt(argv[++c], 0, &parse_error);
       if (picture.width > WEBP_MAX_DIMENSION || picture.width < 0 ||
@@ -711,30 +735,30 @@ int main(int argc, const char *argv[]) {
                 picture.width, picture.height);
         goto Error;
       }
-    } else if (!strcmp(argv[c], "-m") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-m") && c + 1 < argc) {
       config.method = ExUtilGetInt(argv[++c], 0, &parse_error);
       use_lossless_preset = 0;   // disable -z option
-    } else if (!strcmp(argv[c], "-q") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-q") && c + 1 < argc) {
       config.quality = ExUtilGetFloat(argv[++c], &parse_error);
       use_lossless_preset = 0;   // disable -z option
-    } else if (!strcmp(argv[c], "-z") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-z") && c + 1 < argc) {
       lossless_preset = ExUtilGetInt(argv[++c], 0, &parse_error);
       if (use_lossless_preset != 0) use_lossless_preset = 1;
-    } else if (!strcmp(argv[c], "-alpha_q") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-alpha_q") && c + 1 < argc) {
       config.alpha_quality = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-alpha_method") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-alpha_method") && c + 1 < argc) {
       config.alpha_compression = ExUtilGetInt(argv[++c], 0, &parse_error);
     } else if (!strcmp(argv[c], "-alpha_cleanup")) {
       // This flag is obsolete, does opposite of -exact.
       config.exact = 0;
     } else if (!strcmp(argv[c], "-exact")) {
       config.exact = 1;
-    } else if (!strcmp(argv[c], "-blend_alpha") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-blend_alpha") && c + 1 < argc) {
       blend_alpha = 1;
       // background color is given in hex with an optional '0x' prefix
       background_color = ExUtilGetInt(argv[++c], 16, &parse_error);
       background_color = background_color & 0x00ffffffu;
-    } else if (!strcmp(argv[c], "-alpha_filter") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-alpha_filter") && c + 1 < argc) {
       ++c;
       if (!strcmp(argv[c], "none")) {
         config.alpha_filtering = 0;
@@ -750,10 +774,10 @@ int main(int argc, const char *argv[]) {
       keep_alpha = 0;
     } else if (!strcmp(argv[c], "-lossless")) {
       config.lossless = 1;
-    } else if (!strcmp(argv[c], "-near_lossless") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-near_lossless") && c + 1 < argc) {
       config.near_lossless = ExUtilGetInt(argv[++c], 0, &parse_error);
       config.lossless = 1;  // use near-lossless only with lossless
-    } else if (!strcmp(argv[c], "-hint") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-hint") && c + 1 < argc) {
       ++c;
       if (!strcmp(argv[c], "photo")) {
         config.image_hint = WEBP_HINT_PHOTO;
@@ -765,13 +789,13 @@ int main(int argc, const char *argv[]) {
         fprintf(stderr, "Error! Unrecognized image hint: %s\n", argv[c]);
         goto Error;
       }
-    } else if (!strcmp(argv[c], "-size") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-size") && c + 1 < argc) {
       config.target_size = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-psnr") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-psnr") && c + 1 < argc) {
       config.target_PSNR = ExUtilGetFloat(argv[++c], &parse_error);
-    } else if (!strcmp(argv[c], "-sns") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-sns") && c + 1 < argc) {
       config.sns_strength = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-f") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-f") && c + 1 < argc) {
       config.filter_strength = ExUtilGetInt(argv[++c], 0, &parse_error);
     } else if (!strcmp(argv[c], "-af")) {
       config.autofilter = 1;
@@ -785,27 +809,32 @@ int main(int argc, const char *argv[]) {
       config.filter_type = 1;
     } else if (!strcmp(argv[c], "-nostrong")) {
       config.filter_type = 0;
-    } else if (!strcmp(argv[c], "-sharpness") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-sharpness") && c + 1 < argc) {
       config.filter_sharpness = ExUtilGetInt(argv[++c], 0, &parse_error);
     } else if (!strcmp(argv[c], "-sharp_yuv")) {
       config.use_sharp_yuv = 1;
-    } else if (!strcmp(argv[c], "-pass") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-pass") && c + 1 < argc) {
       config.pass = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-pre") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-qrange") && c + 2 < argc) {
+      config.qmin = ExUtilGetInt(argv[++c], 0, &parse_error);
+      config.qmax = ExUtilGetInt(argv[++c], 0, &parse_error);
+      if (config.qmin < 0) config.qmin = 0;
+      if (config.qmax > 100) config.qmax = 100;
+    } else if (!strcmp(argv[c], "-pre") && c + 1 < argc) {
       config.preprocessing = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-segments") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-segments") && c + 1 < argc) {
       config.segments = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-partition_limit") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-partition_limit") && c + 1 < argc) {
       config.partition_limit = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-map") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-map") && c + 1 < argc) {
       picture.extra_info_type = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-crop") && c < argc - 4) {
+    } else if (!strcmp(argv[c], "-crop") && c + 4 < argc) {
       crop = 1;
       crop_x = ExUtilGetInt(argv[++c], 0, &parse_error);
       crop_y = ExUtilGetInt(argv[++c], 0, &parse_error);
       crop_w = ExUtilGetInt(argv[++c], 0, &parse_error);
       crop_h = ExUtilGetInt(argv[++c], 0, &parse_error);
-    } else if (!strcmp(argv[c], "-resize") && c < argc - 2) {
+    } else if (!strcmp(argv[c], "-resize") && c + 2 < argc) {
       resize_w = ExUtilGetInt(argv[++c], 0, &parse_error);
       resize_h = ExUtilGetInt(argv[++c], 0, &parse_error);
 #ifndef WEBP_DLL
@@ -814,14 +843,18 @@ int main(int argc, const char *argv[]) {
 #endif
     } else if (!strcmp(argv[c], "-version")) {
       const int version = WebPGetEncoderVersion();
+      const int sharpyuv_version = SharpYuvGetVersion();
       printf("%d.%d.%d\n",
              (version >> 16) & 0xff, (version >> 8) & 0xff, version & 0xff);
-      return 0;
+      printf("libsharpyuv: %d.%d.%d\n",
+             (sharpyuv_version >> 24) & 0xff, (sharpyuv_version >> 16) & 0xffff,
+             sharpyuv_version & 0xff);
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else if (!strcmp(argv[c], "-progress")) {
       show_progress = 1;
     } else if (!strcmp(argv[c], "-quiet")) {
       quiet = 1;
-    } else if (!strcmp(argv[c], "-preset") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-preset") && c + 1 < argc) {
       WebPPreset preset;
       ++c;
       if (!strcmp(argv[c], "default")) {
@@ -844,7 +877,7 @@ int main(int argc, const char *argv[]) {
         fprintf(stderr, "Error! Could initialize configuration with preset.\n");
         goto Error;
       }
-    } else if (!strcmp(argv[c], "-metadata") && c < argc - 1) {
+    } else if (!strcmp(argv[c], "-metadata") && c + 1 < argc) {
       static const struct {
         const char* option;
         int flag;
@@ -878,8 +911,7 @@ int main(int argc, const char *argv[]) {
         if (i == kNumTokens) {
           fprintf(stderr, "Error! Unknown metadata type '%.*s'\n",
                   (int)(token - start), start);
-          HelpLong();
+          FREE_WARGV_AND_RETURN(EXIT_FAILURE);
-          return -1;
         }
         start = token + 1;
       }
@@ -893,19 +925,19 @@ int main(int argc, const char *argv[]) {
     } else if (!strcmp(argv[c], "-v")) {
       verbose = 1;
     } else if (!strcmp(argv[c], "--")) {
-      if (c < argc - 1) in_file = argv[++c];
+      if (c + 1 < argc) in_file = (const char*)GET_WARGV(argv, ++c);
       break;
     } else if (argv[c][0] == '-') {
       fprintf(stderr, "Error! Unknown option '%s'\n", argv[c]);
       HelpLong();
-      return -1;
+      FREE_WARGV_AND_RETURN(EXIT_FAILURE);
     } else {
-      in_file = argv[c];
+      in_file = (const char*)GET_WARGV(argv, c);
     }
 
     if (parse_error) {
       HelpLong();
-      return -1;
+      FREE_WARGV_AND_RETURN(EXIT_FAILURE);
     }
   }
   if (in_file == NULL) {
@@ -955,7 +987,8 @@ int main(int argc, const char *argv[]) {
   }
   if (!ReadPicture(in_file, &picture, keep_alpha,
                    (keep_metadata == 0) ? NULL : &metadata)) {
-    fprintf(stderr, "Error! Cannot read input picture file '%s'\n", in_file);
+    WFPRINTF(stderr, "Error! Cannot read input picture file '%s'\n",
+             (const W_CHAR*)in_file);
     goto Error;
   }
   picture.progress_hook = (show_progress && !quiet) ? ProgressReport : NULL;
@@ -968,28 +1001,41 @@ int main(int argc, const char *argv[]) {
     const double read_time = StopwatchReadAndReset(&stop_watch);
     fprintf(stderr, "Time to read input: %.3fs\n", read_time);
   }
+  // The bitstream should be kept in memory when metadata must be appended
+  // before writing it to a file/stream, and/or when the near-losslessly encoded
+  // bitstream must be decoded for distortion computation (lossy will modify the
+  // 'picture' but not the lossless pipeline).
+  // Otherwise directly write the bitstream to a file.
+  use_memory_writer = (out_file != NULL && keep_metadata) ||
+                      (!quiet && print_distortion >= 0 && config.lossless &&
+                       config.near_lossless < 100);
 
   // Open the output
   if (out_file != NULL) {
-    const int use_stdout = !strcmp(out_file, "-");
+    const int use_stdout = !WSTRCMP(out_file, "-");
-    out = use_stdout ? ImgIoUtilSetBinaryMode(stdout) : fopen(out_file, "wb");
+    out = use_stdout ? ImgIoUtilSetBinaryMode(stdout) : WFOPEN(out_file, "wb");
     if (out == NULL) {
-      fprintf(stderr, "Error! Cannot open output file '%s'\n", out_file);
+      WFPRINTF(stderr, "Error! Cannot open output file '%s'\n",
+               (const W_CHAR*)out_file);
       goto Error;
     } else {
       if (!short_output && !quiet) {
-        fprintf(stderr, "Saving file '%s'\n", out_file);
+        WFPRINTF(stderr, "Saving file '%s'\n", (const W_CHAR*)out_file);
       }
     }
-    if (keep_metadata == 0) {
+    if (use_memory_writer) {
-      picture.writer = MyWriter;
-      picture.custom_ptr = (void*)out;
-    } else {
       picture.writer = WebPMemoryWrite;
       picture.custom_ptr = (void*)&memory_writer;
+    } else {
+      picture.writer = MyWriter;
+      picture.custom_ptr = (void*)out;
     }
   } else {
     out = NULL;
+    if (use_memory_writer) {
+      picture.writer = WebPMemoryWrite;
+      picture.custom_ptr = (void*)&memory_writer;
+    }
     if (!quiet && !short_output) {
       fprintf(stderr, "No output file specified (no -o flag). Encoding will\n");
       fprintf(stderr, "be performed, but its results discarded.\n\n");
@@ -1012,10 +1058,53 @@ int main(int argc, const char *argv[]) {
     }
   }
   if ((resize_w | resize_h) > 0) {
+    WebPPicture picture_no_alpha;
+    if (config.exact) {
+      // If -exact, we can't premultiply RGB by A otherwise RGB is lost if A=0.
+      // We rescale an opaque copy and assemble scaled A and non-premultiplied
+      // RGB channels. This is slower but it's a very uncommon use case. Color
+      // leak at sharp alpha edges is possible.
+      if (!WebPPictureCopy(&picture, &picture_no_alpha)) {
+        fprintf(stderr, "Error! Cannot copy temporary picture\n");
+        goto Error;
+      }
+
+      // We enforced picture.use_argb = 1 above. Now, remove the alpha values.
+      {
+        int x, y;
+        uint32_t* argb_no_alpha = picture_no_alpha.argb;
+        for (y = 0; y < picture_no_alpha.height; ++y) {
+          for (x = 0; x < picture_no_alpha.width; ++x) {
+            argb_no_alpha[x] |= 0xff000000;  // Opaque copy.
+          }
+          argb_no_alpha += picture_no_alpha.argb_stride;
+        }
+      }
+
+      if (!WebPPictureRescale(&picture_no_alpha, resize_w, resize_h)) {
+        fprintf(stderr, "Error! Cannot resize temporary picture\n");
+        goto Error;
+      }
+    }
+
     if (!WebPPictureRescale(&picture, resize_w, resize_h)) {
       fprintf(stderr, "Error! Cannot resize picture\n");
       goto Error;
     }
+
+    if (config.exact) {  // Put back the alpha information.
+      int x, y;
+      uint32_t* argb_no_alpha = picture_no_alpha.argb;
+      uint32_t* argb = picture.argb;
+      for (y = 0; y < picture_no_alpha.height; ++y) {
+        for (x = 0; x < picture_no_alpha.width; ++x) {
+          argb[x] = (argb[x] & 0xff000000) | (argb_no_alpha[x] & 0x00ffffff);
+        }
+        argb_no_alpha += picture_no_alpha.argb_stride;
+        argb += picture.argb_stride;
+      }
+      WebPPictureFree(&picture_no_alpha);
+    }
   }
   if (verbose && (crop != 0 || (resize_w | resize_h) > 0)) {
     const double preproc_time = StopwatchReadAndReset(&stop_watch);
@@ -1025,8 +1114,12 @@ int main(int argc, const char *argv[]) {
   if (picture.extra_info_type > 0) {
     AllocExtraInfo(&picture);
   }
-  if (print_distortion >= 0) {  // Save original picture for later comparison
+  // Save original picture for later comparison. Only for lossy as lossless does
-    WebPPictureCopy(&picture, &original_picture);
+  // not modify 'picture' (even near-lossless).
+  if (print_distortion >= 0 && !config.lossless &&
+      !WebPPictureCopy(&picture, &original_picture)) {
+    fprintf(stderr, "Error! Cannot copy temporary picture\n");
+    goto Error;
   }
 
   // Compress.
@@ -1044,40 +1137,72 @@ int main(int argc, const char *argv[]) {
     fprintf(stderr, "Time to encode picture: %.3fs\n", encode_time);
   }
 
-  // Write info
+  // Get the decompressed image for the lossless pipeline.
+  if (!quiet && print_distortion >= 0 && config.lossless) {
+    if (config.near_lossless == 100) {
+      // Pure lossless: image was not modified, make 'original_picture' a view
+      // of 'picture' by copying all members except the freeable pointers.
+      original_picture = picture;
+      original_picture.memory_ = original_picture.memory_argb_ = NULL;
+    } else {
+      // Decode the bitstream stored in 'memory_writer' to get the altered image
+      // to 'picture'; save the 'original_picture' beforehand.
+      assert(use_memory_writer);
+      original_picture = picture;
+      if (!WebPPictureInit(&picture)) {  // Do not free 'picture'.
+        fprintf(stderr, "Error! Version mismatch!\n");
+        goto Error;
+      }
+
+      picture.use_argb = 1;
+      if (!ReadWebP(
+              memory_writer.mem, memory_writer.size, &picture,
+              /*keep_alpha=*/WebPPictureHasTransparency(&original_picture),
+              /*metadata=*/NULL)) {
+        fprintf(stderr, "Error! Cannot decode encoded WebP bitstream\n");
+        fprintf(stderr, "Error code: %d (%s)\n", picture.error_code,
+                kErrorMessages[picture.error_code]);
+        goto Error;
+      }
+      picture.stats = original_picture.stats;
+    }
+    original_picture.stats = NULL;
+  }
+
+  // Write the YUV planes to a PGM file. Only available for lossy.
   if (dump_file) {
     if (picture.use_argb) {
-      fprintf(stderr, "Warning: can't dump file (-d option) in lossless mode.");
+      fprintf(stderr, "Warning: can't dump file (-d option) "
+                      "in lossless mode.\n");
     } else if (!DumpPicture(&picture, dump_file)) {
-      fprintf(stderr, "Warning, couldn't dump picture %s\n", dump_file);
+      WFPRINTF(stderr, "Warning, couldn't dump picture %s\n",
+               (const W_CHAR*)dump_file);
     }
   }
 
-  if (keep_metadata != 0) {
+  if (use_memory_writer && out != NULL &&
-    if (out != NULL) {
+      !WriteWebPWithMetadata(out, &picture, &memory_writer, &metadata,
-      if (!WriteWebPWithMetadata(out, &picture, &memory_writer,
+                             keep_metadata, &metadata_written)) {
-                                 &metadata, keep_metadata, &metadata_written)) {
+    fprintf(stderr, "Error writing WebP file!\n");
-        fprintf(stderr, "Error writing WebP file with metadata!\n");
+    goto Error;
-        goto Error;
+  }
-      }
-    } else {  // output is disabled, just display the metadata stats.
-      const struct {
-        const MetadataPayload* const payload;
-        int flag;
-      } *iter, info[] = {
-        { &metadata.exif, METADATA_EXIF },
-        { &metadata.iccp, METADATA_ICC },
-        { &metadata.xmp, METADATA_XMP },
-        { NULL, 0 }
-      };
-      uint32_t unused1 = 0;
-      uint64_t unused2 = 0;
 
-      for (iter = info; iter->payload != NULL; ++iter) {
+  if (out == NULL && keep_metadata) {
-        if (UpdateFlagsAndSize(iter->payload, !!(keep_metadata & iter->flag),
+    // output is disabled, just display the metadata stats.
-                               0, &unused1, &unused2)) {
+    const struct {
-          metadata_written |= iter->flag;
+      const MetadataPayload* const payload;
-        }
+      int flag;
+    } *iter, info[] = {{&metadata.exif, METADATA_EXIF},
+                       {&metadata.iccp, METADATA_ICC},
+                       {&metadata.xmp, METADATA_XMP},
+                       {NULL, 0}};
+    uint32_t unused1 = 0;
+    uint64_t unused2 = 0;
+
+    for (iter = info; iter->payload != NULL; ++iter) {
+      if (UpdateFlagsAndSize(iter->payload, !!(keep_metadata & iter->flag),
+                             /*flag=*/0, &unused1, &unused2)) {
+        metadata_written |= iter->flag;
       }
     }
   }
@@ -1113,11 +1238,11 @@ int main(int argc, const char *argv[]) {
       PrintMetadataInfo(&metadata, metadata_written);
     }
   }
-  return_value = 0;
+  return_value = EXIT_SUCCESS;
 
  Error:
   WebPMemoryWriterClear(&memory_writer);
-  free(picture.extra_info);
+  WebPFree(picture.extra_info);
   MetadataFree(&metadata);
   WebPPictureFree(&picture);
   WebPPictureFree(&original_picture);
@@ -1125,7 +1250,7 @@ int main(int argc, const char *argv[]) {
     fclose(out);
   }
 
-  return return_value;
+  FREE_WARGV_AND_RETURN(return_value);
 }
 
 //------------------------------------------------------------------------------

examples/dwebp.c

@@ -24,6 +24,7 @@
 #include "../imageio/image_enc.h"
 #include "../imageio/webpdec.h"
 #include "./stopwatch.h"
+#include "./unicode.h"
 
 static int verbose = 0;
 static int quiet = 0;
@@ -42,7 +43,7 @@ extern void* VP8GetCPUInfo;   // opaque forward declaration.
 
 static int SaveOutput(const WebPDecBuffer* const buffer,
                       WebPOutputFileFormat format, const char* const out_file) {
-  const int use_stdout = (out_file != NULL) && !strcmp(out_file, "-");
+  const int use_stdout = (out_file != NULL) && !WSTRCMP(out_file, "-");
   int ok = 1;
   Stopwatch stop_watch;
 
@@ -56,7 +57,7 @@ static int SaveOutput(const WebPDecBuffer* const buffer,
       if (use_stdout) {
         fprintf(stderr, "Saved to stdout\n");
       } else {
-        fprintf(stderr, "Saved file %s\n", out_file);
+        WFPRINTF(stderr, "Saved file %s\n", (const W_CHAR*)out_file);
       }
     }
     if (verbose) {
@@ -67,7 +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;
@@ -75,7 +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"
@@ -94,7 +96,7 @@ static void Help(void) {
          "  -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"
-         "  -resize <w> <h> ......... scale the output (*after* any cropping)\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"
@@ -131,7 +133,7 @@ static uint8_t* AllocateExternalBuffer(WebPDecoderConfig* config,
                      format == RGB_565) ? 2
                   : 4;
     uint32_t stride = bpp * w + 7;   // <- just for exercising
-    external_buffer = (uint8_t*)malloc(stride * h);
+    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;
@@ -144,7 +146,7 @@ static uint8_t* AllocateExternalBuffer(WebPDecoderConfig* config,
     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*)malloc(total_size);
+    external_buffer = (uint8_t*)WebPMalloc(total_size);
     if (external_buffer == NULL) return NULL;
     tmp = external_buffer;
     output_buffer->u.YUVA.y = tmp;
@@ -175,10 +177,11 @@ static uint8_t* AllocateExternalBuffer(WebPDecoderConfig* config,
   return external_buffer;
 }
 
-int main(int argc, const char *argv[]) {
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
+int main(int argc, const char* argv[]) {
   int ok = 0;
-  const char *in_file = NULL;
+  const char* in_file = NULL;
-  const char *out_file = NULL;
+  const char* out_file = NULL;
 
   WebPDecoderConfig config;
   WebPDecBuffer* const output_buffer = &config.output;
@@ -191,18 +194,20 @@ int main(int argc, const char *argv[]) {
   int incremental = 0;
   int c;
 
+  INIT_WARGV(argc, argv);
+
   if (!WebPInitDecoderConfig(&config)) {
     fprintf(stderr, "Library version mismatch!\n");
-    return -1;
+    FREE_WARGV_AND_RETURN(EXIT_FAILURE);
   }
 
   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(EXIT_SUCCESS);
     } 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")) {
@@ -223,7 +228,7 @@ int main(int argc, const char *argv[]) {
       const int version = WebPGetDecoderVersion();
       printf("%d.%d.%d\n",
              (version >> 16) & 0xff, (version >> 8) & 0xff, version & 0xff);
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else if (!strcmp(argv[c], "-pgm")) {
       format = PGM;
     } else if (!strcmp(argv[c], "-yuv")) {
@@ -284,26 +289,26 @@ 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(EXIT_FAILURE);
     } else {
-      in_file = argv[c];
+      in_file = (const char*)GET_WARGV(argv, c);
     }
 
     if (parse_error) {
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(EXIT_FAILURE);
     }
   }
 
   if (in_file == NULL) {
     fprintf(stderr, "missing input file!!\n");
     Help();
-    return -1;
+    FREE_WARGV_AND_RETURN(EXIT_FAILURE);
   }
 
   if (quiet) verbose = 0;
@@ -312,7 +317,7 @@ int main(int argc, const char *argv[]) {
     VP8StatusCode status = VP8_STATUS_OK;
     size_t data_size = 0;
     if (!LoadWebP(in_file, &data, &data_size, bitstream)) {
-      return -1;
+      FREE_WARGV_AND_RETURN(EXIT_FAILURE);
     }
 
     switch (format) {
@@ -389,18 +394,18 @@ int main(int argc, const char *argv[]) {
 
   if (out_file != NULL) {
     if (!quiet) {
-      fprintf(stderr, "Decoded %s. Dimensions: %d x %d %s. Format: %s. "
+      WFPRINTF(stderr, "Decoded %s.", (const W_CHAR*)in_file);
-                      "Now saving...\n",
+      fprintf(stderr, " Dimensions: %d x %d %s. Format: %s. Now saving...\n",
-              in_file, output_buffer->width, output_buffer->height,
+              output_buffer->width, output_buffer->height,
               bitstream->has_alpha ? " (with alpha)" : "",
               kFormatType[bitstream->format]);
     }
     ok = SaveOutput(output_buffer, format, out_file);
   } else {
     if (!quiet) {
-      fprintf(stderr, "File %s can be decoded "
+      WFPRINTF(stderr, "File %s can be decoded ", (const W_CHAR*)in_file);
-                      "(dimensions: %d x %d %s. Format: %s).\n",
+      fprintf(stderr, "(dimensions: %d x %d %s. Format: %s).\n",
-              in_file, output_buffer->width, output_buffer->height,
+              output_buffer->width, output_buffer->height,
               bitstream->has_alpha ? " (with alpha)" : "",
               kFormatType[bitstream->format]);
       fprintf(stderr, "Nothing written; "
@@ -409,9 +414,9 @@ int main(int argc, const char *argv[]) {
   }
  Exit:
   WebPFreeDecBuffer(output_buffer);
-  free((void*)external_buffer);
+  WebPFree((void*)external_buffer);
-  free((void*)data);
+  WebPFree((void*)data);
-  return ok ? 0 : -1;
+  FREE_WARGV_AND_RETURN(ok ? EXIT_SUCCESS : EXIT_FAILURE);
 }
 
 //------------------------------------------------------------------------------

examples/example_util.c

@@ -75,7 +75,7 @@ static void ResetCommandLineArguments(int argc, const char* argv[],
 void ExUtilDeleteCommandLineArguments(CommandLineArguments* const args) {
   if (args != NULL) {
     if (args->own_argv_) {
-      free((void*)args->argv_);
+      WebPFree((void*)args->argv_);
       WebPDataClear(&args->argv_data_);
     }
     ResetCommandLineArguments(0, NULL, args);
@@ -90,12 +90,23 @@ int ExUtilInitCommandLineArguments(int argc, const char* argv[],
   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**)malloc(MAX_ARGC * sizeof(*args->argv_));
+    args->argv_ = (const char**)WebPMalloc(MAX_ARGC * sizeof(*args->argv_));
-    if (args->argv_ == NULL) return 0;
+    if (args->argv_ == NULL) {
+      ExUtilDeleteCommandLineArguments(args);
+      return 0;
+    }
 
     argc = 0;
     for (cur = strtok((char*)args->argv_data_.bytes, sep);
@@ -103,6 +114,7 @@ int ExUtilInitCommandLineArguments(int argc, const char* argv[],
          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);

examples/gif2webp.c

@@ -33,6 +33,8 @@
 #include "../examples/example_util.h"
 #include "../imageio/imageio_util.h"
 #include "./gifdec.h"
+#include "./unicode.h"
+#include "./unicode_gif.h"
 
 #if !defined(STDIN_FILENO)
 #define STDIN_FILENO 0
@@ -94,13 +96,13 @@ static void Help(void) {
 
 //------------------------------------------------------------------------------
 
-int main(int argc, const char *argv[]) {
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
+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;
+  const W_CHAR* in_file = NULL, *out_file = NULL;
-  FILE* out = NULL;
   GifFileType* gif = NULL;
   int frame_duration = 0;
   int frame_timestamp = 0;
@@ -133,11 +135,13 @@ int main(int argc, const char *argv[]) {
   int default_kmin = 1;  // Whether to use default kmin value.
   int default_kmax = 1;
 
+  INIT_WARGV(argc, argv);
+
   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(EXIT_FAILURE);
   }
   config.lossless = 1;  // Use lossless compression by default.
 
@@ -147,16 +151,16 @@ int main(int argc, const char *argv[]) {
 
   if (argc == 1) {
     Help();
-    return 0;
+    FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
   }
 
   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(EXIT_SUCCESS);
     } 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")) {
@@ -213,7 +217,7 @@ 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(EXIT_FAILURE);
         }
         start = token + 1;
       }
@@ -226,7 +230,7 @@ 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(EXIT_SUCCESS);
     } else if (!strcmp(argv[c], "-quiet")) {
       quiet = 1;
       enc_options.verbose = 0;
@@ -234,19 +238,19 @@ int main(int argc, const char *argv[]) {
       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(EXIT_FAILURE);
     } else {
-      in_file = argv[c];
+      in_file = GET_WARGV(argv, c);
     }
 
     if (parse_error) {
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(EXIT_FAILURE);
     }
   }
 
@@ -270,13 +274,7 @@ int main(int argc, const char *argv[]) {
   }
 
   // Start the decoder object
-#if LOCAL_GIF_PREREQ(5,0)
+  gif = DGifOpenFileUnicode(in_file, &gif_error);
-  gif = !strcmp(in_file, "-") ? DGifOpenFileHandle(STDIN_FILENO, &gif_error)
-                              : DGifOpenFileName(in_file, &gif_error);
-#else
-  gif = !strcmp(in_file, "-") ? DGifOpenFileHandle(STDIN_FILENO)
-                              : DGifOpenFileName(in_file);
-#endif
   if (gif == NULL) goto End;
 
   // Loop over GIF images
@@ -317,8 +315,11 @@ int main(int argc, const char *argv[]) {
           frame.use_argb = 1;
           if (!WebPPictureAlloc(&frame)) goto End;
           GIFClearPic(&frame, NULL);
-          WebPPictureCopy(&frame, &curr_canvas);
+          if (!(WebPPictureCopy(&frame, &curr_canvas) &&
-          WebPPictureCopy(&frame, &prev_canvas);
+                WebPPictureCopy(&frame, &prev_canvas))) {
+            fprintf(stderr, "Error allocating canvas.\n");
+            goto End;
+          }
 
           // Background color.
           GIFGetBackgroundColor(gif->SColorMap, gif->SBackGroundColor,
@@ -382,7 +383,7 @@ int main(int argc, const char *argv[]) {
       }
       case EXTENSION_RECORD_TYPE: {
         int extension;
-        GifByteType *data = NULL;
+        GifByteType* data = NULL;
         if (DGifGetExtension(gif, &extension, &data) == GIF_ERROR) {
           goto End;
         }
@@ -468,8 +469,10 @@ int main(int argc, const char *argv[]) {
     fprintf(stderr, "%s\n", WebPAnimEncoderGetError(enc));
     goto End;
   }
-
+  // If there's only one frame, we don't need to handle loop count.
-  if (!loop_compatibility) {
+  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
@@ -478,7 +481,7 @@ int main(int argc, const char *argv[]) {
         stored_loop_count = 1;
         loop_count = 1;
       }
-    } else if (loop_count > 0) {
+    } else if (loop_count > 0 && loop_count < 65535) {
       // adapt GIF's semantic to WebP's (except in the infinite-loop case)
       loop_count += 1;
     }
@@ -545,17 +548,18 @@ int main(int argc, const char *argv[]) {
   }
 
   if (out_file != NULL) {
-    if (!ImgIoUtilWriteFile(out_file, webp_data.bytes, webp_data.size)) {
+    if (!ImgIoUtilWriteFile((const char*)out_file, webp_data.bytes,
-      fprintf(stderr, "Error writing output file: %s\n", out_file);
+                            webp_data.size)) {
+      WFPRINTF(stderr, "Error writing output file: %s\n", out_file);
       goto End;
     }
     if (!quiet) {
-      if (!strcmp(out_file, "-")) {
+      if (!WSTRCMP(out_file, "-")) {
         fprintf(stderr, "Saved %d bytes to STDIO\n",
                 (int)webp_data.size);
       } else {
-        fprintf(stderr, "Saved output file (%d bytes): %s\n",
+        WFPRINTF(stderr, "Saved output file (%d bytes): %s\n",
-                (int)webp_data.size, out_file);
+                 (int)webp_data.size, out_file);
       }
     }
   } else {
@@ -578,7 +582,6 @@ int main(int argc, const char *argv[]) {
   WebPPictureFree(&curr_canvas);
   WebPPictureFree(&prev_canvas);
   WebPAnimEncoderDelete(enc);
-  if (out != NULL && out_file != NULL) fclose(out);
 
   if (gif_error != GIF_OK) {
     GIFDisplayError(gif, gif_error);
@@ -591,15 +594,15 @@ int main(int argc, const char *argv[]) {
 #endif
   }
 
-  return !ok;
+  FREE_WARGV_AND_RETURN(ok ? EXIT_SUCCESS : EXIT_FAILURE);
 }
 
 #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;
+  return EXIT_FAILURE;
 }
 
 #endif

examples/gifdec.c

@@ -137,7 +137,7 @@ int GIFReadFrame(GifFileType* const gif, int transparent_index,
   }
   dst = sub_image.argb;
 
-  tmp = (uint8_t*)malloc(rect.width * sizeof(*tmp));
+  tmp = (uint8_t*)WebPMalloc(rect.width * sizeof(*tmp));
   if (tmp == NULL) goto End;
 
   if (image_desc->Interlace) {  // Interlaced image.
@@ -168,7 +168,7 @@ int GIFReadFrame(GifFileType* const gif, int transparent_index,
  End:
   if (!ok) picture->error_code = sub_image.error_code;
   WebPPictureFree(&sub_image);
-  free(tmp);
+  WebPFree(tmp);
   return ok;
 }
 
@@ -317,7 +317,7 @@ void GIFDisplayError(const GifFileType* const gif, int gif_error) {
 
 #else  // !WEBP_HAVE_GIF
 
-static void ErrorGIFNotAvailable() {
+static void ErrorGIFNotAvailable(void) {
   fprintf(stderr, "GIF support not compiled. Please install the libgif-dev "
           "package before building.\n");
 }

examples/img2webp.c

@@ -27,6 +27,8 @@
 #include "../imageio/image_dec.h"
 #include "../imageio/imageio_util.h"
 #include "./stopwatch.h"
+#include "./unicode.h"
+#include "sharpyuv/sharpyuv.h"
 #include "webp/encode.h"
 #include "webp/mux.h"
 
@@ -34,18 +36,22 @@
 
 static void Help(void) {
   printf("Usage:\n\n");
-  printf("  img2webp [file-level options] [image files...] "
+  printf("  img2webp [file_options] [[frame_options] frame_file]...");
-         "[per-frame options...]\n");
+  printf(" [-o webp_file]\n\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(" -near_lossless <int> . use near-lossless image preprocessing\n"
+         "                        (0..100=off), default=100\n");
+  printf(" -sharp_yuv ........... use sharper (and slower) RGB->YUV "
+                                  "conversion\n                        "
+                                  "(lossy only)\n");
+  printf(" -loop <int> .......... loop count (default: 0, = infinite loop)\n");
   printf(" -v ................... verbose mode\n");
   printf(" -h ................... this help\n");
   printf(" -version ............. print version number and exit\n");
@@ -53,14 +59,24 @@ static void Help(void) {
 
   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(" -lossless ............ use lossless mode (default)\n");
-  printf(" -lossy ... ........... use lossy mode\n");
+  printf(" -lossy ............... use lossy mode\n");
   printf(" -q <float> ........... quality\n");
   printf(" -m <int> ............. method to use\n");
+  printf(" -exact, -noexact ..... preserve or alter RGB values in transparent "
+                                  "area\n"
+         "                        (default: -noexact, may cause artifacts\n"
+         "                                  with lossy animations)\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());
 }
 
 //------------------------------------------------------------------------------
@@ -79,7 +95,7 @@ static int ReadImage(const char filename[], WebPPicture* const pic) {
   if (!ImgIoUtilReadFile(filename, &data, &data_size)) return 0;
   reader = WebPGuessImageReader(data, data_size);
   ok = reader(data, data_size, pic, 1, NULL);
-  free((void*)data);
+  WebPFree((void*)data);
   return ok;
 }
 
@@ -118,6 +134,7 @@ static int SetLoopCount(int loop_count, WebPData* const webp_data) {
 
 //------------------------------------------------------------------------------
 
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
 int main(int argc, const char* argv[]) {
   const char* output = NULL;
   WebPAnimEncoder* enc = NULL;
@@ -134,8 +151,13 @@ int main(int argc, const char* argv[]) {
   int c;
   int have_input = 0;
   CommandLineArguments cmd_args;
-  int ok = ExUtilInitCommandLineArguments(argc - 1, argv + 1, &cmd_args);
+  int ok;
-  if (!ok) return 1;
+
+  INIT_WARGV(argc, argv);
+
+  ok = ExUtilInitCommandLineArguments(argc - 1, argv + 1, &cmd_args);
+  if (!ok) FREE_WARGV_AND_RETURN(EXIT_FAILURE);
+
   argc = cmd_args.argc_;
   argv = cmd_args.argv_;
 
@@ -154,7 +176,7 @@ int main(int argc, const char* argv[]) {
       int parse_error = 0;
       if (!strcmp(argv[c], "-o") && c + 1 < argc) {
         argv[c] = NULL;
-        output = argv[++c];
+        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);
@@ -173,18 +195,26 @@ int main(int argc, const char* argv[]) {
       } else if (!strcmp(argv[c], "-mixed")) {
         anim_config.allow_mixed = 1;
         config.lossless = 0;
+      } else if (!strcmp(argv[c], "-near_lossless") && c + 1 < argc) {
+        argv[c] = NULL;
+        config.near_lossless = ExUtilGetInt(argv[++c], 0, &parse_error);
+      } else if (!strcmp(argv[c], "-sharp_yuv")) {
+        config.use_sharp_yuv = 1;
       } else if (!strcmp(argv[c], "-v")) {
         verbose = 1;
       } else if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
         Help();
-        goto End;
+        FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
       } else if (!strcmp(argv[c], "-version")) {
         const int enc_version = WebPGetEncoderVersion();
         const int mux_version = WebPGetMuxVersion();
+        const int sharpyuv_version = SharpYuvGetVersion();
         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);
+        printf("libsharpyuv: %d.%d.%d\n", (sharpyuv_version >> 24) & 0xff,
+               (sharpyuv_version >> 16) & 0xffff, sharpyuv_version & 0xff);
         goto End;
       } else {
         continue;
@@ -222,6 +252,10 @@ int main(int argc, const char* argv[]) {
           fprintf(stderr, "Invalid negative duration (%d)\n", duration);
           parse_error = 1;
         }
+      } else if (!strcmp(argv[c], "-exact")) {
+        config.exact = 1;
+      } else if (!strcmp(argv[c], "-noexact")) {
+        config.exact = 0;
       } else {
         parse_error = 1;   // shouldn't be here.
         fprintf(stderr, "Unknown option [%s]\n", argv[c]);
@@ -241,7 +275,7 @@ int main(int argc, const char* argv[]) {
 
     // read next input image
     pic.use_argb = 1;
-    ok = ReadImage(argv[c], &pic);
+    ok = ReadImage((const char*)GET_WARGV_SHIFTED(argv, c), &pic);
     if (!ok) goto End;
 
     if (enc == NULL) {
@@ -273,8 +307,8 @@ int main(int argc, const char* argv[]) {
     if (!ok) goto End;
 
     if (verbose) {
-      fprintf(stderr, "Added frame #%3d at time %4d (file: %s)\n",
+      WFPRINTF(stderr, "Added frame #%3d at time %4d (file: %s)\n",
-              pic_num, timestamp_ms, argv[c]);
+               pic_num, timestamp_ms, GET_WARGV_SHIFTED(argv, c));
     }
     timestamp_ms += duration;
     ++pic_num;
@@ -298,7 +332,7 @@ int main(int argc, const char* argv[]) {
   if (ok) {
     if (output != NULL) {
       ok = ImgIoUtilWriteFile(output, webp_data.bytes, webp_data.size);
-      if (ok) fprintf(stderr, "output file: %s     ", output);
+      if (ok) WFPRINTF(stderr, "output file: %s     ", (const W_CHAR*)output);
     } else {
       fprintf(stderr, "[no output file specified]   ");
     }
@@ -310,5 +344,5 @@ int main(int argc, const char* argv[]) {
   }
   WebPDataClear(&webp_data);
   ExUtilDeleteCommandLineArguments(&cmd_args);
-  return ok ? 0 : 1;
+  FREE_WARGV_AND_RETURN(ok ? EXIT_SUCCESS : EXIT_FAILURE);
 }

examples/stopwatch.h

@@ -60,4 +60,4 @@ static WEBP_INLINE double StopwatchReadAndReset(Stopwatch* watch) {
 
 #endif   /* _WIN32 */
 
-#endif  /* WEBP_EXAMPLES_STOPWATCH_H_ */
+#endif  // WEBP_EXAMPLES_STOPWATCH_H_

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

@@ -18,6 +18,7 @@
 #define _POSIX_C_SOURCE 200112L  // for setenv
 #endif
 
+#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -42,6 +43,7 @@
 
 #include "../examples/example_util.h"
 #include "../imageio/imageio_util.h"
+#include "./unicode.h"
 
 #if defined(_MSC_VER) && _MSC_VER < 1900
 #define snprintf _snprintf
@@ -56,6 +58,7 @@ static struct {
   int print_info;
   int only_deltas;
   int use_color_profile;
+  int draw_anim_background_color;
 
   int canvas_width, canvas_height;
   int loop_count;
@@ -225,6 +228,9 @@ 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 */) {
@@ -252,9 +258,11 @@ 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') {
-    // Note: doesn't handle refresh of animation's last-frame (it's quite
-    // more involved to do, since you need to save the previous frame).
     kParams.print_info = 1 - kParams.print_info;
     if (!kParams.has_animation) ClearPreviousFrame();
     glutPostRedisplay();
@@ -285,8 +293,21 @@ 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) {
@@ -309,6 +330,43 @@ 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;
@@ -325,38 +383,21 @@ static void HandleDisplay(void) {
   glPixelStorei(GL_UNPACK_ROW_LENGTH, pic->u.RGBA.stride / 4);
 
   if (kParams.only_deltas) {
-    DrawCheckerBoard();
+    DrawBackground();
-  } else if (prev->dispose_method == WEBP_MUX_DISPOSE_BACKGROUND ||
+  } else {
-      curr->blend_method == WEBP_MUX_NO_BLEND) {
+    // The rectangle of the previous frame might be different than the current
-    // glScissor() takes window coordinates (0,0 at bottom left).
+    // frame, so we may need to DrawBackgroundScissored for both.
-    int window_x, window_y;
-    int frame_w, frame_h;
     if (prev->dispose_method == WEBP_MUX_DISPOSE_BACKGROUND) {
       // Clear the previous frame rectangle.
-      window_x = prev->x_offset;
+      DrawBackgroundScissored(prev->x_offset, prev->y_offset, prev->width,
-      window_y = kParams.canvas_height - prev->y_offset - prev->height;
+                              prev->height);
-      frame_w = prev->width;
+    }
-      frame_h = prev->height;
+    if (curr->blend_method == WEBP_MUX_NO_BLEND) {
-    } else {  // curr->blend_method == WEBP_MUX_NO_BLEND.
+      // We simulate no-blending behavior by first clearing the current frame
-      // We simulate no-blending behavior by first clearing the current frame
+      // rectangle and then alpha-blending against it.
-      // rectangle (to a checker-board) and then alpha-blending against it.
+      DrawBackgroundScissored(curr->x_offset, curr->y_offset, curr->width,
-      window_x = curr->x_offset;
+                              curr->height);
-      window_y = kParams.canvas_height - curr->y_offset - curr->height;
-      frame_w = curr->width;
-      frame_h = curr->height;
     }
-    glEnable(GL_SCISSOR_TEST);
-    // 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(window_x, window_y, frame_w, frame_h);
-
-    glClear(GL_COLOR_BUFFER_BIT);  // use clear color
-    DrawCheckerBoard();
-
-    glDisable(GL_SCISSOR_TEST);
   }
 
   *prev = *curr;
@@ -369,7 +410,7 @@ 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);
@@ -390,9 +431,13 @@ static void HandleDisplay(void) {
 #endif
 }
 
-static void StartDisplay(void) {
+static void StartDisplay(const char* filename) {
-  const int width = kParams.canvas_width;
+  int width = kParams.canvas_width;
-  const int height = kParams.canvas_height;
+  int height = kParams.canvas_height;
+  int screen_width, screen_height;
+  const char viewername[] = " - WebP viewer";
+  // max linux file len + viewername string
+  char title[4096 + sizeof(viewername)] = "";
   // TODO(webp:365) GLUT_DOUBLE results in flickering / old frames to be
   // partially displayed with animated webp + alpha.
 #if defined(__APPLE__) || defined(_WIN32)
@@ -400,65 +445,80 @@ static void StartDisplay(void) {
 #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;
+    }
+  }
+  snprintf(title, sizeof(title), "%s%s", filename, viewername);
   glutInitWindowSize(width, height);
-  glutCreateWindow("WebP viewer");
+  glutCreateWindow(title);
   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),
+  glClearColor(0, 0, 0, 0);  // window will be cleared to black (no blend)
-               GetColorf(kParams.bg_color, 8),
+  DrawBackground();
-               GetColorf(kParams.bg_color, 16),
-               GetColorf(kParams.bg_color, 24));
-  glClear(GL_COLOR_BUFFER_BIT);
-  DrawCheckerBoard();
 }
 
 //------------------------------------------------------------------------------
 // Main
 
 static void Help(void) {
-  printf("Usage: vwebp in_file [options]\n\n"
+  printf(
-         "Decodes the WebP image file and visualize it using OpenGL\n"
+      "Usage: vwebp in_file [options]\n\n"
-         "Options are:\n"
+      "Decodes the WebP image file and visualize it using OpenGL\n"
-         "  -version ..... print version number and exit\n"
+      "Options are:\n"
-         "  -noicc ....... don't use the icc profile if present\n"
+      "  -version ..... print version number and exit\n"
-         "  -nofancy ..... don't use the fancy YUV420 upscaler\n"
+      "  -noicc ....... don't use the icc profile if present\n"
-         "  -nofilter .... disable in-loop filtering\n"
+      "  -nofancy ..... don't use the fancy YUV420 upscaler\n"
-         "  -dither <int>  dithering strength (0..100), default=50\n"
+      "  -nofilter .... disable in-loop filtering\n"
-         "  -noalphadither disable alpha plane dithering\n"
+      "  -dither <int>  dithering strength (0..100), default=50\n"
-         "  -mt .......... use multi-threading\n"
+      "  -noalphadither disable alpha plane dithering\n"
-         "  -info ........ print info\n"
+      "  -usebgcolor .. display background color\n"
-         "  -h ........... this help message\n"
+      "  -mt .......... use multi-threading\n"
-         "\n"
+      "  -info ........ print info\n"
-         "Keyboard shortcuts:\n"
+      "  -h ........... this help message\n"
-         "  'c' ................ toggle use of color profile\n"
+      "\n"
-         "  'i' ................ overlay file information\n"
+      "Keyboard shortcuts:\n"
-         "  'd' ................ disable blending & disposal (debug)\n"
+      "  'c' ................ toggle use of color profile\n"
-         "  'q' / 'Q' / ESC .... quit\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;
+  int c, file_name_argv_index = 1;
   WebPDecoderConfig* const config = &kParams.config;
   WebPIterator* const curr = &kParams.curr_frame;
 
+  INIT_WARGV(argc, argv);
+
   if (!WebPInitDecoderConfig(config)) {
     fprintf(stderr, "Library version mismatch!\n");
-    return -1;
+    FREE_WARGV_AND_RETURN(EXIT_FAILURE);
   }
   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(EXIT_SUCCESS);
     } else if (!strcmp(argv[c], "-noicc")) {
       kParams.use_color_profile = 0;
     } else if (!strcmp(argv[c], "-nofancy")) {
@@ -467,6 +527,8 @@ int main(int argc, char *argv[]) {
       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 =
           ExUtilGetInt(argv[++c], 0, &parse_error);
@@ -479,30 +541,34 @@ 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(EXIT_SUCCESS);
     } 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);
+        file_name_argv_index = c;
+      }
       break;
     } else if (argv[c][0] == '-') {
       printf("Unknown option '%s'\n", argv[c]);
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(EXIT_FAILURE);
     } else {
-      kParams.file_name = argv[c];
+      kParams.file_name = (const char*)GET_WARGV(argv, c);
+      file_name_argv_index = c;
     }
 
     if (parse_error) {
       Help();
-      return -1;
+      FREE_WARGV_AND_RETURN(EXIT_FAILURE);
     }
   }
 
   if (kParams.file_name == NULL) {
     printf("missing input file!!\n");
     Help();
-    return 0;
+    FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
   }
 
   if (!ImgIoUtilReadFile(kParams.file_name,
@@ -556,7 +622,7 @@ int main(int argc, char *argv[]) {
 
   // Position iterator to last frame. Next call to HandleDisplay will wrap over.
   // We take this into account by bumping up loop_count.
-  WebPDemuxGetFrame(kParams.dmux, 0, curr);
+  if (!WebPDemuxGetFrame(kParams.dmux, 0, curr)) goto Error;
   if (kParams.loop_count) ++kParams.loop_count;
 
 #if defined(__unix__) || defined(__CYGWIN__)
@@ -570,26 +636,26 @@ int main(int argc, char *argv[]) {
 #ifdef FREEGLUT
   glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE, GLUT_ACTION_CONTINUE_EXECUTION);
 #endif
-  StartDisplay();
+  StartDisplay(argv[file_name_argv_index]);
 
   if (kParams.has_animation) glutTimerFunc(0, decode_callback, 0);
   glutMainLoop();
 
   // Should only be reached when using FREEGLUT:
   ClearParams();
-  return 0;
+  FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
 
  Error:
   ClearParams();
-  return -1;
+  FREE_WARGV_AND_RETURN(EXIT_FAILURE);
 }
 
 #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;
+  return EXIT_FAILURE;
 }
 
 #endif

examples/webpinfo.c

@@ -14,12 +14,14 @@
 
 #include <assert.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #ifdef HAVE_CONFIG_H
 #include "webp/config.h"
 #endif
 
 #include "../imageio/imageio_util.h"
+#include "./unicode.h"
 #include "webp/decode.h"
 #include "webp/format_constants.h"
 #include "webp/mux_types.h"
@@ -40,6 +42,7 @@
     if (webp_info->show_diagnosis_) {            \
       fprintf(stderr, "Warning: %s\n", MESSAGE); \
     }                                            \
+    ++webp_info->num_warnings_;                  \
   } while (0)
 
 static const char* const kFormats[3] = {
@@ -115,6 +118,7 @@ typedef struct WebPInfo {
   int is_processing_anim_frame_, seen_alpha_subchunk_, seen_image_subchunk_;
   // Print output control.
   int quiet_, show_diagnosis_, show_summary_;
+  int num_warnings_;
   int parse_bitstream_;
 } WebPInfo;
 
@@ -122,16 +126,16 @@ static void WebPInfoInit(WebPInfo* const webp_info) {
   memset(webp_info, 0, sizeof(*webp_info));
 }
 
-static const char kWebPChunkTags[CHUNK_TYPES][4] = {
+static const uint32_t kWebPChunkTags[CHUNK_TYPES] = {
-  { 'V', 'P', '8', ' ' },
+  MKFOURCC('V', 'P', '8', ' '),
-  { 'V', 'P', '8', 'L' },
+  MKFOURCC('V', 'P', '8', 'L'),
-  { 'V', 'P', '8', 'X' },
+  MKFOURCC('V', 'P', '8', 'X'),
-  { 'A', 'L', 'P', 'H' },
+  MKFOURCC('A', 'L', 'P', 'H'),
-  { 'A', 'N', 'I', 'M' },
+  MKFOURCC('A', 'N', 'I', 'M'),
-  { 'A', 'N', 'M', 'F' },
+  MKFOURCC('A', 'N', 'M', 'F'),
-  { 'I', 'C', 'C', 'P' },
+  MKFOURCC('I', 'C', 'C', 'P'),
-  { 'E', 'X', 'I', 'F' },
+  MKFOURCC('E', 'X', 'I', 'F'),
-  { 'X', 'M', 'P', ' ' },
+  MKFOURCC('X', 'M', 'P', ' '),
 };
 
 // -----------------------------------------------------------------------------
@@ -354,12 +358,12 @@ static WebPInfoStatus ParseLossyHeader(const ChunkData* const chunk_data,
   }
   data += 3;
   data_size -= 3;
-  printf("  Key frame:        %s\n"
+  printf(
-         "  Profile:          %d\n"
+      "  Key frame:        %s\n"
-         "  Display:          %s\n"
+      "  Profile:          %d\n"
-         "  Part. 0 length:   %d\n",
+      "  Display:          Yes\n"
-         key_frame ? "Yes" : "No", profile,
+      "  Part. 0 length:   %d\n",
-         display ? "Yes" : "No", partition0_length);
+      key_frame ? "Yes" : "No", profile, partition0_length);
   if (key_frame) {
     if (!(data[0] == 0x9d && data[1] == 0x01 && data[2] == 0x2a)) {
       LOG_ERROR("Invalid lossy bitstream signature.");
@@ -579,7 +583,7 @@ static WebPInfoStatus ParseAlphaHeader(const ChunkData* const chunk_data,
 // -----------------------------------------------------------------------------
 // Chunk parsing.
 
-static WebPInfoStatus ParseRIFFHeader(const WebPInfo* const webp_info,
+static WebPInfoStatus ParseRIFFHeader(WebPInfo* const webp_info,
                                       MemBuffer* const mem) {
   const size_t min_size = RIFF_HEADER_SIZE + CHUNK_HEADER_SIZE;
   size_t riff_size;
@@ -641,7 +645,7 @@ static WebPInfoStatus ParseChunk(const WebPInfo* const webp_info,
       return WEBP_INFO_TRUNCATED_DATA;
     }
     for (i = 0; i < CHUNK_TYPES; ++i) {
-      if (!memcmp(kWebPChunkTags[i], &fourcc, TAG_SIZE)) break;
+      if (kWebPChunkTags[i] == fourcc) break;
     }
     chunk_data->offset_ = chunk_start_offset;
     chunk_data->size_ = chunk_size;
@@ -936,7 +940,13 @@ static WebPInfoStatus ProcessChunk(const ChunkData* const chunk_data,
     LOG_WARN(error_message);
   } else {
     if (!webp_info->quiet_) {
-      const char* tag = kWebPChunkTags[chunk_data->id_];
+      char tag[4];
+      uint32_t fourcc = kWebPChunkTags[chunk_data->id_];
+#ifdef WORDS_BIGENDIAN
+      fourcc = (fourcc >> 24) | ((fourcc >> 8) & 0xff00) |
+               ((fourcc << 8) & 0xff0000) | (fourcc << 24);
+#endif
+      memcpy(tag, &fourcc, sizeof(tag));
       printf("Chunk %c%c%c%c at offset %6d, length %6d\n",
              tag[0], tag[1], tag[2], tag[3], (int)chunk_data->offset_,
              (int)chunk_data->size_);
@@ -987,7 +997,7 @@ static WebPInfoStatus ProcessChunk(const ChunkData* const chunk_data,
   return status;
 }
 
-static WebPInfoStatus Validate(const WebPInfo* const webp_info) {
+static WebPInfoStatus Validate(WebPInfo* const webp_info) {
   if (webp_info->num_frames_ < 1) {
     LOG_ERROR("No image/frame detected.");
     return WEBP_INFO_MISSING_DATA;
@@ -1092,16 +1102,14 @@ static WebPInfoStatus AnalyzeWebP(WebPInfo* const webp_info,
     } else {
       printf("Errors detected.\n");
     }
+    if (webp_info->num_warnings_ > 0) {
+      printf("There were %d warning(s).\n", webp_info->num_warnings_);
+    }
   }
   return webp_info_status;
 }
 
-static void HelpShort(void) {
+static void Help(void) {
-  printf("Usage: webpinfo [options] in_files\n"
-         "Try -longhelp for an exhaustive list of options.\n");
-}
-
-static void HelpLong(void) {
   printf("Usage: webpinfo [options] in_files\n"
          "Note: there could be multiple input files;\n"
          "      options must come before input files.\n"
@@ -1113,25 +1121,26 @@ static void HelpLong(void) {
          "  -bitstream_info .... Parse bitstream header.\n");
 }
 
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
 int main(int argc, const char* argv[]) {
   int c, quiet = 0, show_diag = 0, show_summary = 0;
   int parse_bitstream = 0;
   WebPInfoStatus webp_info_status = WEBP_INFO_OK;
   WebPInfo webp_info;
 
+  INIT_WARGV(argc, argv);
+
   if (argc == 1) {
-    HelpShort();
+    Help();
-    return WEBP_INFO_OK;
+    FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
   }
 
   // Parse command-line input.
   for (c = 1; c < argc; ++c) {
-    if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
+    if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help") ||
-      HelpShort();
+        !strcmp(argv[c], "-H") || !strcmp(argv[c], "-longhelp")) {
-      return WEBP_INFO_OK;
+      Help();
-    } else if (!strcmp(argv[c], "-H") || !strcmp(argv[c], "-longhelp")) {
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
-      HelpLong();
-      return WEBP_INFO_OK;
     } else if (!strcmp(argv[c], "-quiet")) {
       quiet = 1;
     } else if (!strcmp(argv[c], "-diag")) {
@@ -1144,35 +1153,37 @@ int main(int argc, const char* argv[]) {
       const int version = WebPGetDecoderVersion();
       printf("WebP Decoder version: %d.%d.%d\n",
              (version >> 16) & 0xff, (version >> 8) & 0xff, version & 0xff);
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else {  // Assume the remaining are all input files.
       break;
     }
   }
 
   if (c == argc) {
-    HelpShort();
+    Help();
-    return WEBP_INFO_INVALID_COMMAND;
+    FREE_WARGV_AND_RETURN(EXIT_FAILURE);
   }
 
   // Process input files one by one.
   for (; c < argc; ++c) {
     WebPData webp_data;
-    const char* in_file = NULL;
+    const W_CHAR* in_file = NULL;
     WebPInfoInit(&webp_info);
     webp_info.quiet_ = quiet;
     webp_info.show_diagnosis_ = show_diag;
     webp_info.show_summary_ = show_summary;
     webp_info.parse_bitstream_ = parse_bitstream;
-    in_file = argv[c];
+    in_file = GET_WARGV(argv, c);
-    if (in_file == NULL || !ReadFileToWebPData(in_file, &webp_data)) {
+    if (in_file == NULL ||
+        !ReadFileToWebPData((const char*)in_file, &webp_data)) {
       webp_info_status = WEBP_INFO_INVALID_COMMAND;
-      fprintf(stderr, "Failed to open input file %s.\n", in_file);
+      WFPRINTF(stderr, "Failed to open input file %s.\n", in_file);
       continue;
     }
-    if (!webp_info.quiet_) printf("File: %s\n", in_file);
+    if (!webp_info.quiet_) WPRINTF("File: %s\n", in_file);
     webp_info_status = AnalyzeWebP(&webp_info, &webp_data);
     WebPDataClear(&webp_data);
   }
-  return webp_info_status;
+  FREE_WARGV_AND_RETURN((webp_info_status == WEBP_INFO_OK) ? EXIT_SUCCESS
+                                                           : EXIT_FAILURE);
 }

examples/webpmux.c

@@ -26,6 +26,7 @@
     webpmux -set icc image_profile.icc in.webp -o out_icc_container.webp
     webpmux -set exif image_metadata.exif in.webp -o out_exif_container.webp
     webpmux -set xmp image_metadata.xmp in.webp -o out_xmp_container.webp
+    webpmux -set loop 1 in.webp -o out_looped.webp
 
   Extract relevant data from WebP container file:
     webpmux -get frame n in.webp -o out_frame.webp
@@ -58,10 +59,12 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+
 #include "webp/decode.h"
 #include "webp/mux.h"
 #include "../examples/example_util.h"
 #include "../imageio/imageio_util.h"
+#include "./unicode.h"
 
 //------------------------------------------------------------------------------
 // Config object to parse command-line arguments.
@@ -96,6 +99,8 @@ typedef enum {
   FEATURE_ICCP,
   FEATURE_ANMF,
   FEATURE_DURATION,
+  FEATURE_LOOP,
+  FEATURE_BGCOLOR,
   LAST_FEATURE
 } FeatureType;
 
@@ -146,16 +151,20 @@ static const char* ErrorString(WebPMuxError err) {
 }
 
 #define RETURN_IF_ERROR(ERR_MSG)                                     \
-  if (err != WEBP_MUX_OK) {                                          \
+  do {                                                               \
-    fprintf(stderr, ERR_MSG);                                        \
+    if (err != WEBP_MUX_OK) {                                        \
-    return err;                                                      \
+      fprintf(stderr, ERR_MSG);                                      \
-  }
+      return err;                                                    \
+    }                                                                \
+  } while (0)
 
 #define RETURN_IF_ERROR3(ERR_MSG, FORMAT_STR1, FORMAT_STR2)          \
-  if (err != WEBP_MUX_OK) {                                          \
+  do {                                                               \
-    fprintf(stderr, ERR_MSG, FORMAT_STR1, FORMAT_STR2);              \
+    if (err != WEBP_MUX_OK) {                                        \
-    return err;                                                      \
+      fprintf(stderr, ERR_MSG, FORMAT_STR1, FORMAT_STR2);            \
-  }
+      return err;                                                    \
+    }                                                                \
+  } while (0)
 
 #define ERROR_GOTO1(ERR_MSG, LABEL)                                  \
   do {                                                               \
@@ -312,10 +321,12 @@ static void PrintHelp(void) {
 
   printf("\n");
   printf("SET_OPTIONS:\n");
-  printf(" Set color profile/metadata:\n");
+  printf(" Set color profile/metadata/parameters:\n");
-  printf("   icc  file.icc     set ICC profile\n");
+  printf("   loop LOOP_COUNT            set the loop count\n");
-  printf("   exif file.exif    set EXIF metadata\n");
+  printf("   bgcolor BACKGROUND_COLOR   set the animation background color\n");
-  printf("   xmp  file.xmp     set XMP metadata\n");
+  printf("   icc  file.icc              set ICC profile\n");
+  printf("   exif file.exif             set EXIF metadata\n");
+  printf("   xmp  file.xmp              set XMP metadata\n");
   printf("   where:    'file.icc' contains the ICC profile to be set,\n");
   printf("             'file.exif' contains the EXIF metadata to be set\n");
   printf("             'file.xmp' contains the XMP metadata to be set\n");
@@ -323,7 +334,7 @@ static void PrintHelp(void) {
   printf("\n");
   printf("DURATION_OPTIONS:\n");
   printf(" Set duration of selected frames:\n");
-  printf("   duration            set duration for each frames\n");
+  printf("   duration            set duration for all frames\n");
   printf("   duration,frame      set duration of a particular frame\n");
   printf("   duration,start,end  set duration of frames in the\n");
   printf("                        interval [start,end])\n");
@@ -342,7 +353,7 @@ static void PrintHelp(void) {
   printf("\n");
   printf("FRAME_OPTIONS(i):\n");
   printf(" Create animation:\n");
-  printf("   file_i +di+[xi+yi[+mi[bi]]]\n");
+  printf("   file_i +di[+xi+yi[+mi[bi]]]\n");
   printf("   where:    'file_i' is the i'th animation frame (WebP format),\n");
   printf("             'di' is the pause duration before next frame,\n");
   printf("             'xi','yi' specify the image offset for this frame,\n");
@@ -390,23 +401,25 @@ static int CreateMux(const char* const filename, WebPMux** mux) {
   *mux = WebPMuxCreate(&bitstream, 1);
   WebPDataClear(&bitstream);
   if (*mux != NULL) return 1;
-  fprintf(stderr, "Failed to create mux object from file %s.\n", filename);
+  WFPRINTF(stderr, "Failed to create mux object from file %s.\n",
+           (const W_CHAR*)filename);
   return 0;
 }
 
 static int WriteData(const char* filename, const WebPData* const webpdata) {
   int ok = 0;
-  FILE* fout = strcmp(filename, "-") ? fopen(filename, "wb")
+  FILE* fout = WSTRCMP(filename, "-") ? WFOPEN(filename, "wb")
-                                     : ImgIoUtilSetBinaryMode(stdout);
+                                      : ImgIoUtilSetBinaryMode(stdout);
   if (fout == NULL) {
-    fprintf(stderr, "Error opening output WebP file %s!\n", filename);
+    WFPRINTF(stderr, "Error opening output WebP file %s!\n",
+             (const W_CHAR*)filename);
     return 0;
   }
   if (fwrite(webpdata->bytes, webpdata->size, 1, fout) != 1) {
-    fprintf(stderr, "Error writing file %s!\n", filename);
+    WFPRINTF(stderr, "Error writing file %s!\n", (const W_CHAR*)filename);
   } else {
-    fprintf(stderr, "Saved file %s (%d bytes)\n",
+    WFPRINTF(stderr, "Saved file %s (%d bytes)\n",
-            filename, (int)webpdata->size);
+             (const W_CHAR*)filename, (int)webpdata->size);
     ok = 1;
   }
   if (fout != stdout) fclose(fout);
@@ -452,7 +465,8 @@ static WebPMux* DuplicateMuxHeader(const WebPMux* const mux) {
     if (err == WEBP_MUX_OK && metadata.size > 0) {
       err = WebPMuxSetChunk(new_mux, kFourccList[i], &metadata, 1);
       if (err != WEBP_MUX_OK) {
-        ERROR_GOTO1("Error transferring metadata in DuplicateMux().", End);
+        ERROR_GOTO1("Error transferring metadata in DuplicateMuxHeader().",
+                    End);
       }
     }
   }
@@ -466,11 +480,11 @@ static WebPMux* DuplicateMuxHeader(const WebPMux* const mux) {
 }
 
 static int ParseFrameArgs(const char* args, WebPMuxFrameInfo* const info) {
-  int dispose_method, dummy;
+  int dispose_method, unused;
   char plus_minus, blend_method;
   const int num_args = sscanf(args, "+%d+%d+%d+%d%c%c+%d", &info->duration,
                               &info->x_offset, &info->y_offset, &dispose_method,
-                              &plus_minus, &blend_method, &dummy);
+                              &plus_minus, &blend_method, &unused);
   switch (num_args) {
     case 1:
       info->x_offset = info->y_offset = 0;  // fall through
@@ -489,7 +503,7 @@ static int ParseFrameArgs(const char* args, WebPMuxFrameInfo* const info) {
 
   WarnAboutOddOffset(info);
 
-  // Note: The sanity of the following conversion is checked by
+  // Note: The validity of the following conversion is checked by
   // WebPMuxPushFrame().
   info->dispose_method = (WebPMuxAnimDispose)dispose_method;
 
@@ -595,26 +609,39 @@ static int ValidateCommandLine(const CommandLineArguments* const cmd_args,
 
 #define FEATURETYPE_IS_NIL (config->type_ == NIL_FEATURE)
 
-#define CHECK_NUM_ARGS_LESS(NUM, LABEL)                                  \
+#define CHECK_NUM_ARGS_AT_LEAST(NUM, LABEL)                              \
-  if (argc < i + (NUM)) {                                                \
+  do {                                                                   \
-    fprintf(stderr, "ERROR: Too few arguments for '%s'.\n", argv[i]);    \
+    if (argc < i + (NUM)) {                                              \
-    goto LABEL;                                                          \
+      fprintf(stderr, "ERROR: Too few arguments for '%s'.\n", argv[i]);  \
-  }
+      goto LABEL;                                                        \
+    }                                                                    \
+  } while (0)
 
-#define CHECK_NUM_ARGS_NOT_EQUAL(NUM, LABEL)                             \
+#define CHECK_NUM_ARGS_AT_MOST(NUM, LABEL)                               \
-  if (argc != i + (NUM)) {                                               \
+  do {                                                                   \
-    fprintf(stderr, "ERROR: Too many arguments for '%s'.\n", argv[i]);   \
+    if (argc > i + (NUM)) {                                              \
-    goto LABEL;                                                          \
+      fprintf(stderr, "ERROR: Too many arguments for '%s'.\n", argv[i]); \
-  }
+      goto LABEL;                                                        \
+    }                                                                    \
+  } while (0)
+
+#define CHECK_NUM_ARGS_EXACTLY(NUM, LABEL)                               \
+  do {                                                                   \
+    CHECK_NUM_ARGS_AT_LEAST(NUM, LABEL);                                 \
+    CHECK_NUM_ARGS_AT_MOST(NUM, LABEL);                                  \
+  } while (0)
 
 // Parses command-line arguments to fill up config object. Also performs some
-// semantic checks.
+// semantic checks. unicode_argv contains wchar_t arguments or is null.
-static int ParseCommandLine(Config* config) {
+static int ParseCommandLine(Config* config, const W_CHAR** const unicode_argv) {
   int i = 0;
   int feature_arg_index = 0;
   int ok = 1;
   int argc = config->cmd_args_.argc_;
   const char* const* argv = config->cmd_args_.argv_;
+  // Unicode file paths will be used if available.
+  const char* const* wargv =
+      (unicode_argv != NULL) ? (const char**)(unicode_argv + 1) : argv;
 
   while (i < argc) {
     FeatureArg* const arg = &config->args_[feature_arg_index];
@@ -627,7 +654,7 @@ static int ParseCommandLine(Config* config) {
         }
         ++i;
       } else if (!strcmp(argv[i], "-duration")) {
-        CHECK_NUM_ARGS_LESS(2, ErrParse);
+        CHECK_NUM_ARGS_AT_LEAST(2, ErrParse);
         if (ACTION_IS_NIL || config->action_type_ == ACTION_DURATION) {
           config->action_type_ = ACTION_DURATION;
         } else {
@@ -657,7 +684,7 @@ static int ParseCommandLine(Config* config) {
         }
         ++i;
       } else if (!strcmp(argv[i], "-frame")) {
-        CHECK_NUM_ARGS_LESS(3, ErrParse);
+        CHECK_NUM_ARGS_AT_LEAST(3, ErrParse);
         if (ACTION_IS_NIL || config->action_type_ == ACTION_SET) {
           config->action_type_ = ACTION_SET;
         } else {
@@ -669,12 +696,12 @@ static int ParseCommandLine(Config* config) {
           ERROR_GOTO1("ERROR: Multiple features specified.\n", ErrParse);
         }
         arg->subtype_ = SUBTYPE_ANMF;
-        arg->filename_ = argv[i + 1];
+        arg->filename_ = wargv[i + 1];
         arg->params_ = argv[i + 2];
         ++feature_arg_index;
         i += 3;
       } else if (!strcmp(argv[i], "-loop") || !strcmp(argv[i], "-bgcolor")) {
-        CHECK_NUM_ARGS_LESS(2, ErrParse);
+        CHECK_NUM_ARGS_AT_LEAST(2, ErrParse);
         if (ACTION_IS_NIL || config->action_type_ == ACTION_SET) {
           config->action_type_ = ACTION_SET;
         } else {
@@ -691,34 +718,36 @@ static int ParseCommandLine(Config* config) {
         ++feature_arg_index;
         i += 2;
       } else if (!strcmp(argv[i], "-o")) {
-        CHECK_NUM_ARGS_LESS(2, ErrParse);
+        CHECK_NUM_ARGS_AT_LEAST(2, ErrParse);
-        config->output_ = argv[i + 1];
+        config->output_ = wargv[i + 1];
         i += 2;
       } else if (!strcmp(argv[i], "-info")) {
-        CHECK_NUM_ARGS_NOT_EQUAL(2, ErrParse);
+        CHECK_NUM_ARGS_EXACTLY(2, ErrParse);
         if (config->action_type_ != NIL_ACTION) {
           ERROR_GOTO1("ERROR: Multiple actions specified.\n", ErrParse);
         } else {
           config->action_type_ = ACTION_INFO;
           config->arg_count_ = 0;
-          config->input_ = argv[i + 1];
+          config->input_ = wargv[i + 1];
         }
         i += 2;
       } else if (!strcmp(argv[i], "-h") || !strcmp(argv[i], "-help")) {
         PrintHelp();
         DeleteConfig(config);
+        LOCAL_FREE((W_CHAR** const)unicode_argv);
         exit(0);
       } else if (!strcmp(argv[i], "-version")) {
         const int version = WebPGetMuxVersion();
         printf("%d.%d.%d\n",
                (version >> 16) & 0xff, (version >> 8) & 0xff, version & 0xff);
         DeleteConfig(config);
+        LOCAL_FREE((W_CHAR** const)unicode_argv);
         exit(0);
       } else if (!strcmp(argv[i], "--")) {
         if (i < argc - 1) {
           ++i;
           if (config->input_ == NULL) {
-            config->input_ = argv[i];
+            config->input_ = wargv[i];
           } else {
             ERROR_GOTO2("ERROR at '%s': Multiple input files specified.\n",
                         argv[i], ErrParse);
@@ -742,8 +771,8 @@ static int ParseCommandLine(Config* config) {
           ERROR_GOTO1("ERROR: Multiple features specified.\n", ErrParse);
         }
         if (config->action_type_ == ACTION_SET) {
-          CHECK_NUM_ARGS_LESS(2, ErrParse);
+          CHECK_NUM_ARGS_AT_LEAST(2, ErrParse);
-          arg->filename_ = argv[i + 1];
+          arg->filename_ = wargv[i + 1];
           ++feature_arg_index;
           i += 2;
         } else {
@@ -751,14 +780,28 @@ static int ParseCommandLine(Config* config) {
         }
       } else if (!strcmp(argv[i], "frame") &&
                  (config->action_type_ == ACTION_GET)) {
-        CHECK_NUM_ARGS_LESS(2, ErrParse);
+        CHECK_NUM_ARGS_AT_LEAST(2, ErrParse);
         config->type_ = FEATURE_ANMF;
         arg->params_ = argv[i + 1];
         ++feature_arg_index;
         i += 2;
+      } else if (!strcmp(argv[i], "loop") &&
+                 (config->action_type_ == ACTION_SET)) {
+        CHECK_NUM_ARGS_AT_LEAST(2, ErrParse);
+        config->type_ = FEATURE_LOOP;
+        arg->params_ = argv[i + 1];
+        ++feature_arg_index;
+        i += 2;
+      } else if (!strcmp(argv[i], "bgcolor") &&
+                 (config->action_type_ == ACTION_SET)) {
+        CHECK_NUM_ARGS_AT_LEAST(2, ErrParse);
+        config->type_ = FEATURE_BGCOLOR;
+        arg->params_ = argv[i + 1];
+        ++feature_arg_index;
+        i += 2;
       } else {  // Assume input file.
         if (config->input_ == NULL) {
-          config->input_ = argv[i];
+          config->input_ = wargv[i];
         } else {
           ERROR_GOTO2("ERROR at '%s': Multiple input files specified.\n",
                       argv[i], ErrParse);
@@ -804,8 +847,8 @@ static int ValidateConfig(Config* const config) {
 }
 
 // Create config object from command-line arguments.
-static int InitializeConfig(int argc, const char* argv[],
+static int InitializeConfig(int argc, const char* argv[], Config* const config,
-                            Config* const config) {
+                            const W_CHAR** const unicode_argv) {
   int num_feature_args = 0;
   int ok;
 
@@ -826,7 +869,7 @@ static int InitializeConfig(int argc, const char* argv[],
   }
 
   // Parse command-line.
-  if (!ParseCommandLine(config) || !ValidateConfig(config)) {
+  if (!ParseCommandLine(config, unicode_argv) || !ValidateConfig(config)) {
     ERROR_GOTO1("Exiting due to command-line parsing error.\n", Err1);
   }
 
@@ -836,8 +879,9 @@ static int InitializeConfig(int argc, const char* argv[],
 
 #undef ACTION_IS_NIL
 #undef FEATURETYPE_IS_NIL
-#undef CHECK_NUM_ARGS_LESS
+#undef CHECK_NUM_ARGS_AT_LEAST
-#undef CHECK_NUM_ARGS_MORE
+#undef CHECK_NUM_ARGS_AT_MOST
+#undef CHECK_NUM_ARGS_EXACTLY
 
 //------------------------------------------------------------------------------
 // Processing.
@@ -998,13 +1042,62 @@ static int Process(const Config* config) {
           ok = ExUtilReadFileToWebPData(config->args_[0].filename_, &chunk);
           if (!ok) goto Err2;
           err = WebPMuxSetChunk(mux, kFourccList[config->type_], &chunk, 1);
-          free((void*)chunk.bytes);
+          WebPDataClear(&chunk);
           if (err != WEBP_MUX_OK) {
             ERROR_GOTO3("ERROR (%s): Could not set the %s.\n",
                         ErrorString(err), kDescriptions[config->type_], Err2);
           }
           break;
         }
+        case FEATURE_LOOP: {
+          WebPMuxAnimParams params = { 0xFFFFFFFF, 0 };
+          int parse_error = 0;
+          const int loop_count =
+              ExUtilGetInt(config->args_[0].params_, 10, &parse_error);
+          if (loop_count < 0 || loop_count > 65535 || parse_error) {
+            ERROR_GOTO1("ERROR: Loop count must be in the range 0 to 65535.\n",
+                        Err2);
+          }
+          ok = CreateMux(config->input_, &mux);
+          if (!ok) goto Err2;
+          ok = (WebPMuxGetAnimationParams(mux, &params) == WEBP_MUX_OK);
+          if (!ok) {
+            ERROR_GOTO1("ERROR: input file does not seem to be an animation.\n",
+                        Err2);
+          }
+          params.loop_count = loop_count;
+          err = WebPMuxSetAnimationParams(mux, &params);
+          ok = (err == WEBP_MUX_OK);
+          if (!ok) {
+            ERROR_GOTO2("ERROR (%s): Could not set animation parameters.\n",
+                        ErrorString(err), Err2);
+          }
+          break;
+        }
+        case FEATURE_BGCOLOR: {
+          WebPMuxAnimParams params = { 0xFFFFFFFF, 0 };
+          uint32_t bgcolor;
+          ok = ParseBgcolorArgs(config->args_[0].params_, &bgcolor);
+          if (!ok) {
+            ERROR_GOTO1("ERROR: Could not parse the background color.\n",
+                        Err2);
+          }
+          ok = CreateMux(config->input_, &mux);
+          if (!ok) goto Err2;
+          ok = (WebPMuxGetAnimationParams(mux, &params) == WEBP_MUX_OK);
+          if (!ok) {
+            ERROR_GOTO1("ERROR: input file does not seem to be an animation.\n",
+                        Err2);
+          }
+          params.bgcolor = bgcolor;
+          err = WebPMuxSetAnimationParams(mux, &params);
+          ok = (err == WEBP_MUX_OK);
+          if (!ok) {
+            ERROR_GOTO2("ERROR (%s): Could not set animation parameters.\n",
+                        ErrorString(err), Err2);
+          }
+          break;
+        }
         default: {
           ERROR_GOTO1("ERROR: Invalid feature for action 'set'.\n", Err2);
           break;
@@ -1032,7 +1125,7 @@ static int Process(const Config* config) {
         int* durations = NULL;
         WebPMux* new_mux = DuplicateMuxHeader(mux);
         if (new_mux == NULL) goto Err2;
-        durations = (int*)malloc((size_t)num_frames * sizeof(*durations));
+        durations = (int*)WebPMalloc((size_t)num_frames * sizeof(*durations));
         if (durations == NULL) goto Err2;
         for (i = 0; i < num_frames; ++i) durations[i] = -1;
 
@@ -1090,7 +1183,7 @@ static int Process(const Config* config) {
         new_mux = NULL;
 
  Err3:
-        free(durations);
+        WebPFree(durations);
         WebPMuxDelete(new_mux);
         if (!ok) goto Err2;
       }
@@ -1133,16 +1226,21 @@ static int Process(const Config* config) {
 //------------------------------------------------------------------------------
 // Main.
 
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
 int main(int argc, const char* argv[]) {
   Config config;
-  int ok = InitializeConfig(argc - 1, argv + 1, &config);
+  int ok;
+
+  INIT_WARGV(argc, argv);
+
+  ok = InitializeConfig(argc - 1, argv + 1, &config, GET_WARGV_OR_NULL());
   if (ok) {
     ok = Process(&config);
   } else {
     PrintHelp();
   }
   DeleteConfig(&config);
-  return !ok;
+  FREE_WARGV_AND_RETURN(ok ? EXIT_SUCCESS : EXIT_FAILURE);
 }
 
 //------------------------------------------------------------------------------

extras/Makefile.am

@@ -7,6 +7,7 @@ noinst_HEADERS += ../src/webp/types.h
 
 libwebpextras_la_SOURCES =
 libwebpextras_la_SOURCES += extras.c extras.h quality_estimate.c
+libwebpextras_la_SOURCES += sharpyuv_risk_table.c sharpyuv_risk_table.h
 
 libwebpextras_la_CPPFLAGS = $(AM_CPPFLAGS)
 libwebpextras_la_LDFLAGS = -lm
@@ -14,7 +15,7 @@ libwebpextras_la_LIBADD = ../src/libwebp.la
 
 noinst_PROGRAMS =
 noinst_PROGRAMS += webp_quality
-if WANT_DEMUX
+if BUILD_DEMUX
   noinst_PROGRAMS += get_disto
 endif
 if BUILD_VWEBP_SDL

extras/extras.c

@@ -11,13 +11,20 @@
 //
 
 #include "extras/extras.h"
-#include "webp/format_constants.h"
 
 #include <assert.h>
+#include <limits.h>
 #include <string.h>
 
+#include "extras/sharpyuv_risk_table.h"
+#include "sharpyuv/sharpyuv.h"
+#include "src/dsp/dsp.h"
+#include "src/utils/utils.h"
+#include "webp/format_constants.h"
+#include "webp/types.h"
+
 #define XTRA_MAJ_VERSION 1
-#define XTRA_MIN_VERSION 0
+#define XTRA_MIN_VERSION 4
 #define XTRA_REV_VERSION 0
 
 //------------------------------------------------------------------------------
@@ -57,7 +64,7 @@ int WebPImportRGB565(const uint8_t* rgb565, WebPPicture* pic) {
   for (y = 0; y < pic->height; ++y) {
     const int width = pic->width;
     for (x = 0; x < width; ++x) {
-#ifdef WEBP_SWAP_16BIT_CSP
+#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
@@ -90,7 +97,7 @@ int WebPImportRGB4444(const uint8_t* rgb4444, WebPPicture* pic) {
   for (y = 0; y < pic->height; ++y) {
     const int width = pic->width;
     for (x = 0; x < width; ++x) {
-#ifdef WEBP_SWAP_16BIT_CSP
+#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
@@ -144,3 +151,174 @@ int WebPImportColorMappedARGB(const uint8_t* indexed, int indexed_stride,
 }
 
 //------------------------------------------------------------------------------
+
+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;
+}
+
+//------------------------------------------------------------------------------
+// 420 risk metric
+
+#define YUV_FIX 16  // fixed-point precision for RGB->YUV
+static const int kYuvHalf = 1 << (YUV_FIX - 1);
+
+// Maps a value in [0, (256 << YUV_FIX) - 1] to [0,
+// precomputed_scores_table_sampling - 1]. It is important that the extremal
+// values are preserved and 1:1 mapped:
+//  ConvertValue(0) = 0
+//  ConvertValue((256 << 16) - 1) = rgb_sampling_size - 1
+static int SharpYuvConvertValueToSampledIdx(int v, int rgb_sampling_size) {
+  v = (v + kYuvHalf) >> YUV_FIX;
+  v = (v < 0) ? 0 : (v > 255) ? 255 : v;
+  return (v * (rgb_sampling_size - 1)) / 255;
+}
+
+#undef YUV_FIX
+
+// For each pixel, computes the index to look up that color in a precomputed
+// risk score table where the YUV space is subsampled to a size of
+// precomputed_scores_table_sampling^3 (see sharpyuv_risk_table.h)
+static int SharpYuvConvertToYuvSharpnessIndex(
+    int r, int g, int b, const SharpYuvConversionMatrix* matrix,
+    int precomputed_scores_table_sampling) {
+  const int y = SharpYuvConvertValueToSampledIdx(
+      matrix->rgb_to_y[0] * r + matrix->rgb_to_y[1] * g +
+          matrix->rgb_to_y[2] * b + matrix->rgb_to_y[3],
+      precomputed_scores_table_sampling);
+  const int u = SharpYuvConvertValueToSampledIdx(
+      matrix->rgb_to_u[0] * r + matrix->rgb_to_u[1] * g +
+          matrix->rgb_to_u[2] * b + matrix->rgb_to_u[3],
+      precomputed_scores_table_sampling);
+  const int v = SharpYuvConvertValueToSampledIdx(
+      matrix->rgb_to_v[0] * r + matrix->rgb_to_v[1] * g +
+          matrix->rgb_to_v[2] * b + matrix->rgb_to_v[3],
+      precomputed_scores_table_sampling);
+  return y + u * precomputed_scores_table_sampling +
+         v * precomputed_scores_table_sampling *
+             precomputed_scores_table_sampling;
+}
+
+static void SharpYuvRowToYuvSharpnessIndex(
+    const uint8_t* r_ptr, const uint8_t* g_ptr, const uint8_t* b_ptr,
+    int rgb_step, int rgb_bit_depth, int width, uint16_t* dst,
+    const SharpYuvConversionMatrix* matrix,
+    int precomputed_scores_table_sampling) {
+  int i;
+  assert(rgb_bit_depth == 8);
+  (void)rgb_bit_depth;  // Unused for now.
+  for (i = 0; i < width;
+       ++i, r_ptr += rgb_step, g_ptr += rgb_step, b_ptr += rgb_step) {
+    dst[i] =
+        SharpYuvConvertToYuvSharpnessIndex(r_ptr[0], g_ptr[0], b_ptr[0], matrix,
+                                           precomputed_scores_table_sampling);
+  }
+}
+
+#define SAFE_ALLOC(W, H, T) ((T*)WebPSafeMalloc((uint64_t)(W) * (H), sizeof(T)))
+
+static int DoEstimateRisk(const uint8_t* r_ptr, const uint8_t* g_ptr,
+                          const uint8_t* b_ptr, int rgb_step, int rgb_stride,
+                          int rgb_bit_depth, int width, int height,
+                          const SharpYuvOptions* options,
+                          const uint8_t precomputed_scores_table[],
+                          int precomputed_scores_table_sampling,
+                          float* score_out) {
+  const int sampling3 = precomputed_scores_table_sampling *
+                        precomputed_scores_table_sampling *
+                        precomputed_scores_table_sampling;
+  const int kNoiseLevel = 4;
+  double total_score = 0;
+  double count = 0;
+  // Rows of indices in
+  uint16_t* row1 = SAFE_ALLOC(width, 1, uint16_t);
+  uint16_t* row2 = SAFE_ALLOC(width, 1, uint16_t);
+  uint16_t* tmp;
+  int i, j;
+
+  if (row1 == NULL || row2 == NULL) {
+    WebPFree(row1);
+    WebPFree(row2);
+    return 0;
+  }
+
+  // Convert the first row ahead.
+  SharpYuvRowToYuvSharpnessIndex(r_ptr, g_ptr, b_ptr, rgb_step, rgb_bit_depth,
+                                 width, row2, options->yuv_matrix,
+                                 precomputed_scores_table_sampling);
+
+  for (j = 1; j < height; ++j) {
+    r_ptr += rgb_stride;
+    g_ptr += rgb_stride;
+    b_ptr += rgb_stride;
+    // Swap row 1 and row 2.
+    tmp = row1;
+    row1 = row2;
+    row2 = tmp;
+    // Convert the row below.
+    SharpYuvRowToYuvSharpnessIndex(r_ptr, g_ptr, b_ptr, rgb_step, rgb_bit_depth,
+                                   width, row2, options->yuv_matrix,
+                                   precomputed_scores_table_sampling);
+    for (i = 0; i < width - 1; ++i) {
+      const int idx0 = row1[i + 0];
+      const int idx1 = row1[i + 1];
+      const int idx2 = row2[i + 0];
+      const int score = precomputed_scores_table[idx0 + sampling3 * idx1] +
+                        precomputed_scores_table[idx0 + sampling3 * idx2] +
+                        precomputed_scores_table[idx1 + sampling3 * idx2];
+      if (score > kNoiseLevel) {
+        total_score += score;
+        count += 1.0;
+      }
+    }
+  }
+  if (count > 0.) total_score /= count;
+
+  // If less than 1% of pixels were evaluated -> below noise level.
+  if (100. * count / (width * height) < 1.) total_score = 0.;
+
+  // Rescale to [0:100]
+  total_score = (total_score > 25.) ? 100. : total_score * 100. / 25.;
+
+  WebPFree(row1);
+  WebPFree(row2);
+
+  *score_out = (float)total_score;
+  return 1;
+}
+
+#undef SAFE_ALLOC
+
+int SharpYuvEstimate420Risk(const void* r_ptr, const void* g_ptr,
+                            const void* b_ptr, int rgb_step, int rgb_stride,
+                            int rgb_bit_depth, int width, int height,
+                            const SharpYuvOptions* options, float* score) {
+  if (width < 1 || height < 1 || width == INT_MAX || height == INT_MAX ||
+      r_ptr == NULL || g_ptr == NULL || b_ptr == NULL || options == NULL ||
+      score == NULL) {
+    return 0;
+  }
+  if (rgb_bit_depth != 8) {
+    return 0;
+  }
+
+  if (width <= 4 || height <= 4) {
+    *score = 0.0f;  // too small, no real risk.
+    return 1;
+  }
+
+  return DoEstimateRisk(
+      (const uint8_t*)r_ptr, (const uint8_t*)g_ptr, (const uint8_t*)b_ptr,
+      rgb_step, rgb_stride, rgb_bit_depth, width, height, options,
+      kSharpYuvPrecomputedRisk, kSharpYuvPrecomputedRiskYuvSampling, score);
+}
+
+//------------------------------------------------------------------------------

extras/extras.h

@@ -17,9 +17,10 @@
 extern "C" {
 #endif
 
+#include "sharpyuv/sharpyuv.h"
 #include "webp/encode.h"
 
-#define WEBP_EXTRAS_ABI_VERSION 0x0001    // MAJOR(8b) + MINOR(8b)
+#define WEBP_EXTRAS_ABI_VERSION 0x0003    // MAJOR(8b) + MINOR(8b)
 
 //------------------------------------------------------------------------------
 
@@ -51,6 +52,13 @@ 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
@@ -63,8 +71,40 @@ WEBP_EXTERN int VP8EstimateQuality(const uint8_t* const data, size_t size);
 
 //------------------------------------------------------------------------------
 
+// Computes a score between 0 and 100 which represents the risk of having visual
+// quality loss from converting an RGB image to YUV420.
+// A low score, typically < 40, means there is a low risk of artifacts from
+// chroma subsampling and a simple averaging algorithm can be used instead of
+// the more expensive SharpYuvConvert function.
+// A medium score, typically >= 40 and < 70, means that simple chroma
+// subsampling will produce artifacts and it may be advisable to use the more
+// costly SharpYuvConvert for YUV420 conversion.
+// A high score, typically >= 70, means there is a very high risk of artifacts
+// from chroma subsampling even with SharpYuvConvert, and best results might be
+// achieved by using YUV444.
+// If not using SharpYuvConvert, a threshold of about 50 can be used to decide
+// between (simple averaging) 420 and 444.
+// r_ptr, g_ptr, b_ptr: pointers to the source r, g and b channels. Should point
+//     to uint8_t buffers if rgb_bit_depth is 8, or uint16_t buffers otherwise.
+// rgb_step: distance in bytes between two horizontally adjacent pixels on the
+//     r, g and b channels. If rgb_bit_depth is > 8, it should be a
+//     multiple of 2.
+// rgb_stride: distance in bytes between two vertically adjacent pixels on the
+//     r, g, and b channels. If rgb_bit_depth is > 8, it should be a
+//     multiple of 2.
+// rgb_bit_depth: number of bits for each r/g/b value. Only a value of 8 is
+//     currently supported.
+// width, height: width and height of the image in pixels
+// Returns 0 on failure.
+WEBP_EXTERN int SharpYuvEstimate420Risk(
+    const void* r_ptr, const void* g_ptr, const void* b_ptr, int rgb_step,
+    int rgb_stride, int rgb_bit_depth, int width, int height,
+    const SharpYuvOptions* options, float* score);
+
+//------------------------------------------------------------------------------
+
 #ifdef __cplusplus
 }    // extern "C"
 #endif
 
-#endif  /* WEBP_EXTRAS_EXTRAS_H_ */
+#endif  // WEBP_EXTRAS_EXTRAS_H_

extras/get_disto.c

@@ -26,6 +26,7 @@
 #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) {
@@ -48,7 +49,8 @@ static size_t ReadPicture(const char* const filename, WebPPicture* const pic,
 
  End:
   if (!ok) {
-    fprintf(stderr, "Error! Could not process file %s\n", filename);
+    WFPRINTF(stderr, "Error! Could not process file %s\n",
+             (const W_CHAR*)filename);
   }
   free((void*)data);
   return ok ? data_size : 0;
@@ -221,13 +223,15 @@ static void Help(void) {
           "  -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"
-          " Also handles PNG, JPG and TIFF files, in addition to WebP.\n");
+          "\nSupported input formats:\n  %s\n",
+          WebPGetEnabledInputFileFormats());
 }
 
-int main(int argc, const char *argv[]) {
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
+int main(int argc, const char* argv[]) {
   WebPPicture pic1, pic2;
   size_t size1 = 0, size2 = 0;
-  int ret = 1;
+  int ret = EXIT_FAILURE;
   float disto[5];
   int type = 0;
   int c;
@@ -239,9 +243,11 @@ int main(int argc, const char *argv[]) {
   const char* name2 = NULL;
   const char* output = NULL;
 
+  INIT_WARGV(argc, argv);
+
   if (!WebPPictureInit(&pic1) || !WebPPictureInit(&pic2)) {
     fprintf(stderr, "Can't init pictures\n");
-    return 1;
+    FREE_WARGV_AND_RETURN(EXIT_FAILURE);
   }
 
   for (c = 1; c < argc; ++c) {
@@ -257,17 +263,17 @@ int main(int argc, const char *argv[]) {
       use_gray = 1;
     } else if (!strcmp(argv[c], "-h")) {
       help = 1;
-      ret = 0;
+      ret = EXIT_SUCCESS;
     } else if (!strcmp(argv[c], "-o")) {
       if (++c == argc) {
         fprintf(stderr, "missing file name after %s option.\n", argv[c - 1]);
         goto End;
       }
-      output = argv[c];
+      output = (const char*)GET_WARGV(argv, c);
     } else if (name1 == NULL) {
-      name1 = argv[c];
+      name1 = (const char*)GET_WARGV(argv, c);
     } else {
-      name2 = argv[c];
+      name2 = (const char*)GET_WARGV(argv, c);
     }
   }
   if (help || name1 == NULL || name2 == NULL) {
@@ -332,7 +338,8 @@ int main(int argc, const char *argv[]) {
       fprintf(stderr, "Error during lossless encoding.\n");
       goto End;
     }
-    ret = ImgIoUtilWriteFile(output, data, data_size) ? 0 : 1;
+    ret = ImgIoUtilWriteFile(output, data, data_size) ? EXIT_SUCCESS
+                                                      : EXIT_FAILURE;
     WebPFree(data);
     if (ret) goto End;
 #else
@@ -340,12 +347,13 @@ int main(int argc, const char *argv[]) {
     (void)data_size;
     fprintf(stderr, "Cannot save the difference map. Please recompile "
                     "without the WEBP_REDUCE_CSP flag.\n");
+    goto End;
 #endif  // WEBP_REDUCE_CSP
   }
-  ret = 0;
+  ret = EXIT_SUCCESS;
 
  End:
   WebPPictureFree(&pic1);
   WebPPictureFree(&pic2);
-  return ret;
+  FREE_WARGV_AND_RETURN(ret);
 }

extras/sharpyuv_risk_table.h

@@ -0,0 +1,27 @@
+// Copyright 2023 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.
+// -----------------------------------------------------------------------------
+//
+// Precomputed data for 420 risk estimation.
+
+#ifndef WEBP_EXTRAS_SHARPYUV_RISK_TABLE_H_
+#define WEBP_EXTRAS_SHARPYUV_RISK_TABLE_H_
+
+#include "src/webp/types.h"
+
+extern const int kSharpYuvPrecomputedRiskYuvSampling;
+// Table of precomputed risk scores when chroma subsampling images with two
+// given colors.
+// Since precomputing values for all possible YUV colors would create a huge
+// table, the YUV space (i.e. [0, 255]^3) is reduced to
+// [0, kSharpYuvPrecomputedRiskYuvSampling-1]^3
+// where 255 maps to kSharpYuvPrecomputedRiskYuvSampling-1.
+// Table size: kSharpYuvPrecomputedRiskYuvSampling^6 bytes or 114 KiB
+extern const uint8_t kSharpYuvPrecomputedRisk[];
+
+#endif  // WEBP_EXTRAS_SHARPYUV_RISK_TABLE_H_

extras/vwebp_sdl.c

@@ -15,6 +15,7 @@
 // Author: James Zern (jzern@google.com)
 
 #include <stdio.h>
+#include <stdlib.h>
 
 #ifdef HAVE_CONFIG_H
 #include "webp/config.h"
@@ -25,11 +26,12 @@
 #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>
+#include <SDL2/SDL.h>
 #endif
 
 static void ProcessEvents(void) {
@@ -48,32 +50,37 @@ static void ProcessEvents(void) {
   }
 }
 
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
 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]);
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else {
-      file = argv[c];
+      file = (const char*)GET_WARGV(argv, c);
     }
     if (file == NULL) continue;
     if (!ImgIoUtilReadFile(file, &webp, &webp_size)) {
-      fprintf(stderr, "Error opening file: %s\n", file);
+      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);
+    ok = WebPToSDL((const char*)webp, (int)webp_size);
     free((void*)webp);
     if (!ok) {
-      fprintf(stderr, "Error decoding file %s\n", file);
+      WFPRINTF(stderr, "Error decoding file %s\n", (const W_CHAR*)file);
       goto Error;
     }
     ProcessEvents();
@@ -82,12 +89,12 @@ int main(int argc, char* argv[]) {
 
  Error:
   SDL_Quit();
-  return ok ? 0 : 1;
+  FREE_WARGV_AND_RETURN(ok ? EXIT_SUCCESS : EXIT_FAILURE);
 }
 
 #else  // !WEBP_HAVE_SDL
 
-int main(int argc, const char *argv[]) {
+int main(int argc, const char* argv[]) {
   fprintf(stderr, "SDL support not enabled in %s.\n", argv[0]);
   (void)argc;
   return 0;

extras/webp_quality.c

@@ -13,26 +13,31 @@
 
 #include "extras/extras.h"
 #include "imageio/imageio_util.h"
+#include "../examples/unicode.h"
 
-int main(int argc, const char *argv[]) {
+// Returns EXIT_SUCCESS on success, EXIT_FAILURE on failure.
+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");
-      return 0;
+      FREE_WARGV_AND_RETURN(EXIT_SUCCESS);
     } else {
-      const char* const filename = argv[c];
+      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) printf("[%s] ", filename);
+      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;
@@ -46,5 +51,5 @@ int main(int argc, const char *argv[]) {
       free((void*)data);
     }
   }
-  return ok ? 0 : 1;
+  FREE_WARGV_AND_RETURN(ok ? EXIT_SUCCESS : EXIT_FAILURE);
 }

extras/webp_to_sdl.c

@@ -20,88 +20,75 @@
 #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>
+#include <SDL2/SDL.h>
 #endif
 
 static int init_ok = 0;
-int WebpToSDL(const char* data, unsigned int data_size) {
+int WebPToSDL(const char* data, unsigned int data_size) {
   int ok = 0;
   VP8StatusCode status;
-  WebPDecoderConfig config;
+  WebPBitstreamFeatures input;
-  WebPBitstreamFeatures* const input = &config.input;
+  uint8_t* output = NULL;
-  WebPDecBuffer* const output = &config.output;
+  SDL_Window* window = NULL;
-  SDL_Surface* screen = NULL;
+  SDL_Renderer* renderer = NULL;
-  SDL_Surface* surface = NULL;
+  SDL_Texture* texture = NULL;
-
+  int width, height;
-  if (!WebPInitDecoderConfig(&config)) {
-    fprintf(stderr, "Library version mismatch!\n");
-    return 1;
-  }
 
   if (!init_ok) {
     SDL_Init(SDL_INIT_VIDEO);
     init_ok = 1;
   }
 
-  status = WebPGetFeatures((uint8_t*)data, (size_t)data_size, &config.input);
+  status = WebPGetFeatures((uint8_t*)data, (size_t)data_size, &input);
   if (status != VP8_STATUS_OK) goto Error;
+  width = input.width;
+  height = input.height;
 
-  screen = SDL_SetVideoMode(input->width, input->height, 32, SDL_SWSURFACE);
+  SDL_CreateWindowAndRenderer(width, height, 0, &window, &renderer);
-  if (screen == NULL) {
+  if (window == NULL || renderer == NULL) {
-    fprintf(stderr, "Unable to set video mode (32bpp %dx%d)!\n",
+    fprintf(stderr, "Unable to create window or renderer!\n");
-            input->width, input->height);
     goto Error;
   }
+  SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY,
+              "linear");  // make the scaled rendering look smoother.
+  SDL_RenderSetLogicalSize(renderer, width, height);
 
-  surface = SDL_CreateRGBSurface(SDL_SWSURFACE,
+  texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ABGR8888,
-                                 input->width, input->height, 32,
+                              SDL_TEXTUREACCESS_STREAMING, width, height);
-                                 0x000000ffu,   // R mask
+  if (texture == NULL) {
-                                 0x0000ff00u,   // G mask
+    fprintf(stderr, "Unable to create %dx%d RGBA texture!\n", width, height);
-                                 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;
+  output = WebPDecodeBGRA((const uint8_t*)data, (size_t)data_size, &width,
+                          &height);
 #else
-  output->colorspace = MODE_RGBA;
+  output = WebPDecodeRGBA((const uint8_t*)data, (size_t)data_size, &width,
+                          &height);
 #endif
-  output->width  = surface->w;
+  if (output == NULL) {
-  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);
+  SDL_UpdateTexture(texture, NULL, output, width * sizeof(uint32_t));
-  if (SDL_BlitSurface(surface, NULL, screen, NULL) ||
+  SDL_RenderClear(renderer);
-      SDL_Flip(screen)) {
+  SDL_RenderCopy(renderer, texture, NULL, NULL);
-    goto Error;
+  SDL_RenderPresent(renderer);
-  }
-
   ok = 1;
 
  Error:
-  SDL_FreeSurface(surface);
+  // We should call SDL_DestroyWindow(window) but that makes .js fail.
-  SDL_FreeSurface(screen);
+  SDL_DestroyRenderer(renderer);
-  WebPFreeDecBuffer(output);
+  SDL_DestroyTexture(texture);
+  WebPFree(output);
   return ok;
 }
 

extras/webp_to_sdl.h

@@ -14,9 +14,9 @@
 #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
+// 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);
+extern int WebPToSDL(const char* data, unsigned int data_size);
 
 #endif  // WEBP_EXTRAS_WEBP_TO_SDL_H_

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,5 @@
-#Thu May 12 17:06:25 CEST 2016
 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
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.13-bin.zip

gradlew

@@ -1,4 +1,20 @@
-#!/usr/bin/env bash
+#!/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.
+#
 
 ##############################################################################
 ##
@@ -28,16 +44,16 @@ 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=""
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD="maximum"
 
-warn ( ) {
+warn () {
     echo "$*"
 }
 
-die ( ) {
+die () {
     echo
     echo "$*"
     echo
@@ -109,8 +125,8 @@ if $darwin; then
     GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
 fi
 
-# For Cygwin, switch paths to Windows format before running java
+# For Cygwin or MSYS, switch paths to Windows format before running java
-if $cygwin ; then
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
     APP_HOME=`cygpath --path --mixed "$APP_HOME"`
     CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
     JAVACMD=`cygpath --unix "$JAVACMD"`
@@ -138,27 +154,30 @@ if $cygwin ; then
         else
             eval `echo args$i`="\"$arg\""
         fi
-        i=$((i+1))
+        i=`expr $i + 1`
     done
     case $i in
-        (0) set -- ;;
+        0) set -- ;;
-        (1) set -- "$args0" ;;
+        1) set -- "$args0" ;;
-        (2) set -- "$args0" "$args1" ;;
+        2) set -- "$args0" "$args1" ;;
-        (3) set -- "$args0" "$args1" "$args2" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
-        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
-        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
-        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
-        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
-        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
-        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
     esac
 fi
 
-# Split up the JVM_OPTS And GRADLE_OPTS values into an array, following the shell quoting and substitution rules
+# Escape application args
-function splitJvmOpts() {
+save () {
-    JVM_OPTS=("$@")
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
 }
-eval splitJvmOpts $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS
+APP_ARGS=`save "$@"`
-JVM_OPTS[${#JVM_OPTS[*]}]="-Dorg.gradle.appname=$APP_BASE_NAME"
 
-exec "$JAVACMD" "${JVM_OPTS[@]}" -classpath "$CLASSPATH" org.gradle.wrapper.GradleWrapperMain "$@"
+# 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

@@ -1,90 +1,100 @@
-@if "%DEBUG%" == "" @echo off
+@rem
-@rem ##########################################################################
+@rem Copyright 2015 the original author or authors.
-@rem
+@rem
-@rem  Gradle startup script for Windows
+@rem Licensed under the Apache License, Version 2.0 (the "License");
-@rem
+@rem you may not use this file except in compliance with the License.
-@rem ##########################################################################
+@rem You may obtain a copy of the License at
-
+@rem
-@rem Set local scope for the variables with windows NT shell
+@rem      https://www.apache.org/licenses/LICENSE-2.0
-if "%OS%"=="Windows_NT" setlocal
+@rem
-
+@rem Unless required by applicable law or agreed to in writing, software
-set DIRNAME=%~dp0
+@rem distributed under the License is distributed on an "AS IS" BASIS,
-if "%DIRNAME%" == "" set DIRNAME=.
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-set APP_BASE_NAME=%~n0
+@rem See the License for the specific language governing permissions and
-set APP_HOME=%DIRNAME%
+@rem limitations under the License.
-
+@rem
-@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=
+@if "%DEBUG%" == "" @echo off
-
+@rem ##########################################################################
-@rem Find java.exe
+@rem
-if defined JAVA_HOME goto findJavaFromJavaHome
+@rem  Gradle startup script for Windows
-
+@rem
-set JAVA_EXE=java.exe
+@rem ##########################################################################
-%JAVA_EXE% -version >NUL 2>&1
+
-if "%ERRORLEVEL%" == "0" goto init
+@rem Set local scope for the variables with windows NT shell
-
+if "%OS%"=="Windows_NT" setlocal
-echo.
+
-echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+set DIRNAME=%~dp0
-echo.
+if "%DIRNAME%" == "" set DIRNAME=.
-echo Please set the JAVA_HOME variable in your environment to match the
+set APP_BASE_NAME=%~n0
-echo location of your Java installation.
+set APP_HOME=%DIRNAME%
-
+
-goto fail
+@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"
-:findJavaFromJavaHome
+
-set JAVA_HOME=%JAVA_HOME:"=%
+@rem Find java.exe
-set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
-
+
-if exist "%JAVA_EXE%" goto init
+set JAVA_EXE=java.exe
-
+%JAVA_EXE% -version >NUL 2>&1
-echo.
+if "%ERRORLEVEL%" == "0" goto init
-echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+
-echo.
+echo.
-echo Please set the JAVA_HOME variable in your environment to match the
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
-echo location of your Java installation.
+echo.
-
+echo Please set the JAVA_HOME variable in your environment to match the
-goto fail
+echo location of your Java installation.
-
+
-:init
+goto fail
-@rem Get command-line arguments, handling Windows variants
+
-
+:findJavaFromJavaHome
-if not "%OS%" == "Windows_NT" goto win9xME_args
+set JAVA_HOME=%JAVA_HOME:"=%
-if "%@eval[2+2]" == "4" goto 4NT_args
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
-
+
-:win9xME_args
+if exist "%JAVA_EXE%" goto init
-@rem Slurp the command line arguments.
+
-set CMD_LINE_ARGS=
+echo.
-set _SKIP=2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
-
+echo.
-:win9xME_args_slurp
+echo Please set the JAVA_HOME variable in your environment to match the
-if "x%~1" == "x" goto execute
+echo location of your Java installation.
-
+
-set CMD_LINE_ARGS=%*
+goto fail
-goto execute
+
-
+:init
-:4NT_args
+@rem Get command-line arguments, handling Windows variants
-@rem Get arguments from the 4NT Shell from JP Software
+
-set CMD_LINE_ARGS=%$
+if not "%OS%" == "Windows_NT" goto win9xME_args
-
+
-:execute
+:win9xME_args
-@rem Setup the command line
+@rem Slurp the command line arguments.
-
+set CMD_LINE_ARGS=
-set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+set _SKIP=2
-
+
-@rem Execute Gradle
+:win9xME_args_slurp
-"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+if "x%~1" == "x" goto execute
-
+
-:end
+set CMD_LINE_ARGS=%*
-@rem End local scope for the variables with windows NT shell
+
-if "%ERRORLEVEL%"=="0" goto mainEnd
+:execute
-
+@rem Setup the command line
-:fail
+
-rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
-rem the _cmd.exe /c_ return code!
+
-if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+@rem Execute Gradle
-exit /b 1
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
-
+
-:mainEnd
+:end
-if "%OS%"=="Windows_NT" endlocal
+@rem End local scope for the variables with windows NT shell
-
+if "%ERRORLEVEL%"=="0" goto mainEnd
-:omega
+
+: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

@@ -1,3 +1,5 @@
+# Ignore this file during non-NDK builds.
+ifdef NDK_ROOT
 LOCAL_PATH := $(call my-dir)
 
 ################################################################################
@@ -52,3 +54,4 @@ LOCAL_STATIC_LIBRARIES := imageio_util
 LOCAL_MODULE := imageenc
 
 include $(BUILD_STATIC_LIBRARY)
+endif  # NDK_ROOT

imageio/Makefile.am

@@ -1,7 +1,7 @@
 AM_CPPFLAGS += -I$(top_builddir)/src -I$(top_srcdir)/src
 noinst_LTLIBRARIES =
 noinst_LTLIBRARIES += libimageio_util.la
-if WANT_DEMUX
+if BUILD_DEMUX
   noinst_LTLIBRARIES += libimagedec.la
 endif
 noinst_LTLIBRARIES += libimageenc.la

imageio/image_dec.c

@@ -11,6 +11,24 @@
 
 #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];
 }

imageio/image_dec.h

@@ -41,6 +41,9 @@ typedef enum {
   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,

imageio/image_enc.c

@@ -29,11 +29,13 @@
                          // 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
@@ -61,11 +63,12 @@ static HRESULT CreateOutputStream(const char* out_file_name,
     // 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));
+    IFS(SHCreateStreamOnFile((const LPTSTR)out_file_name,
+                             STGM_WRITE | STGM_CREATE, stream));
   }
   if (FAILED(hr)) {
-    fprintf(stderr, "Error opening output file %s (%08lx)\n",
+    _ftprintf(stderr, _T("Error opening output file %s (%08lx)\n"),
-            out_file_name, hr);
+              (const LPTSTR)out_file_name, hr);
   }
   return hr;
 }
@@ -152,8 +155,8 @@ int WebPWritePNG(const char* out_file_name, int use_stdout,
 }
 
 #elif defined(WEBP_HAVE_PNG)    // !HAVE_WINCODEC_H
-static void PNGAPI PNGErrorFunction(png_structp png, png_const_charp dummy) {
+static void PNGAPI PNGErrorFunction(png_structp png, png_const_charp unused) {
-  (void)dummy;  // remove variable-unused warning
+  (void)unused;  // remove variable-unused warning
   longjmp(png_jmpbuf(png), 1);
 }
 
@@ -257,14 +260,20 @@ int WebPWritePAM(FILE* fout, const WebPDecBuffer* const buffer) {
 
 // Save 16b mode (RGBA4444, RGB565, ...) for debugging purpose.
 int WebPWrite16bAsPGM(FILE* fout, const WebPDecBuffer* const buffer) {
-  const uint32_t width = buffer->width;
+  uint32_t width, height;
-  const uint32_t height = buffer->height;
+  uint8_t* rgba;
-  const uint8_t* rgba = buffer->u.RGBA.rgba;
+  int stride;
-  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;
+  if (fout == NULL || buffer == NULL) return 0;
+
+  width = buffer->width;
+  height = buffer->height;
+  rgba = buffer->u.RGBA.rgba;
+  stride = buffer->u.RGBA.stride;
+
+  if (rgba == NULL) return 0;
 
   fprintf(fout, "P5\n%u %u\n255\n", width * bytes_per_px, height);
   for (y = 0; y < height; ++y) {
@@ -277,7 +286,7 @@ int WebPWrite16bAsPGM(FILE* fout, const WebPDecBuffer* const buffer) {
 }
 
 //------------------------------------------------------------------------------
-// BMP
+// 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;
@@ -290,49 +299,67 @@ static void PutLE32(uint8_t* const dst, uint32_t value) {
 }
 
 #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);
+  int has_alpha, header_size;
-  const uint32_t width = buffer->width;
+  uint32_t width, height;
-  const uint32_t height = buffer->height;
+  uint8_t* rgba;
-  const uint8_t* rgba = buffer->u.RGBA.rgba;
+  int stride;
-  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;
+  uint32_t bytes_per_px, line_size, image_size, bmp_stride, total_size;
-  const uint32_t bmp_stride = (line_size + 3) & ~3;   // pad to 4
+  uint8_t bmp_header[BMP_HEADER_SIZE + BMP_HEADER_ALPHA_EXTRA_SIZE] = { 0 };
-  const uint32_t total_size = bmp_stride * height + BMP_HEADER_SIZE;
-  uint8_t bmp_header[BMP_HEADER_SIZE] = { 0 };
 
-  if (fout == NULL || buffer == NULL || rgba == NULL) return 0;
+  if (fout == NULL || buffer == NULL) return 0;
+
+  has_alpha = WebPIsAlphaMode(buffer->colorspace);
+  header_size = BMP_HEADER_SIZE + (has_alpha ? BMP_HEADER_ALPHA_EXTRA_SIZE : 0);
+  width = buffer->width;
+  height = buffer->height;
+  rgba = buffer->u.RGBA.rgba;
+  stride = buffer->u.RGBA.stride;
+  bytes_per_px = has_alpha ? 4 : 3;
+  line_size = bytes_per_px * width;
+  bmp_stride = (line_size + 3) & ~3;  // pad to 4
+  image_size = bmp_stride * height;
+  total_size = image_size + header_size;
+
+  if (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, BMP_HEADER_SIZE);      // offset to pixel array
+  PutLE32(bmp_header + 10, header_size);          // offset to pixel array
   // bitmap info header
-  PutLE32(bmp_header + 14, 40);                   // DIB header size
+  PutLE32(bmp_header + 14, header_size - 14);     // DIB header size
   PutLE32(bmp_header + 18, width);                // dimensions
-  PutLE32(bmp_header + 22, -(int)height);         // vertical flip!
+  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, 0);                    // no compression (BI_RGB)
+  PutLE32(bmp_header + 30, has_alpha ? 3 : 0);    // BI_BITFIELDS or BI_RGB
-  PutLE32(bmp_header + 34, 0);                    // image size (dummy)
+  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, sizeof(bmp_header), 1, fout) != 1) {
+  if (fwrite(bmp_header, header_size, 1, fout) != 1) {
     return 0;
   }
 
-  // write pixel array
+  // write pixel array, bottom to top
   for (y = 0; y < height; ++y) {
-    if (fwrite(rgba, line_size, 1, fout) != 1) {
+    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
@@ -342,11 +369,11 @@ int WebPWriteBMP(FILE* fout, const WebPDecBuffer* const buffer) {
         return 0;
       }
     }
-    rgba += stride;
   }
   return 1;
 }
 #undef BMP_HEADER_SIZE
+#undef BMP_HEADER_ALPHA_EXTRA_SIZE
 
 //------------------------------------------------------------------------------
 // TIFF
@@ -358,17 +385,14 @@ int WebPWriteBMP(FILE* fout, const WebPDecBuffer* const buffer) {
 #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);
+  int has_alpha;
-  const uint32_t width = buffer->width;
+  uint32_t width, height;
-  const uint32_t height = buffer->height;
+  uint8_t* rgba;
-  const uint8_t* rgba = buffer->u.RGBA.rgba;
+  int stride;
-  const int stride = buffer->u.RGBA.stride;
+  uint8_t bytes_per_px = 0;
-  const uint8_t bytes_per_px = has_alpha ? 4 : 3;
+  const uint8_t assoc_alpha = 0;
-  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
+  const uint8_t num_ifd_entries = 0;
-                                            : 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
@@ -402,7 +426,20 @@ int WebPWriteTIFF(FILE* fout, const WebPDecBuffer* const buffer) {
   };
   uint32_t y;
 
-  if (fout == NULL || buffer == NULL || rgba == NULL) return 0;
+  if (fout == NULL || buffer == NULL) return 0;
+
+  has_alpha = WebPIsAlphaMode(buffer->colorspace);
+  width = buffer->width;
+  height = buffer->height;
+  rgba = buffer->u.RGBA.rgba;
+  stride = buffer->u.RGBA.stride;
+
+  if (rgba == NULL) return 0;
+
+  // Update bytes_per_px, num_ifd_entries and assoc_alpha.
+  tiff_header[38] = tiff_header[102] = bytes_per_px = has_alpha ? 4 : 3;
+  tiff_header[8] = has_alpha ? NUM_IFD_ENTRIES : NUM_IFD_ENTRIES - 1;
+  tiff_header[186] = WebPIsPremultipliedMode(buffer->colorspace) ? 1 : 2;
 
   // Fill placeholders in IFD:
   PutLE32(tiff_header + 10 + 8, width);
@@ -549,7 +586,8 @@ int WebPSaveImage(const WebPDecBuffer* const buffer,
                   const char* const out_file_name) {
   FILE* fout = NULL;
   int needs_open_file = 1;
-  const int use_stdout = (out_file_name != NULL) && !strcmp(out_file_name, "-");
+  const int use_stdout =
+      (out_file_name != NULL) && !WSTRCMP(out_file_name, "-");
   int ok = 1;
 
   if (buffer == NULL || out_file_name == NULL) return 0;
@@ -560,9 +598,10 @@ int WebPSaveImage(const WebPDecBuffer* const buffer,
 
   if (needs_open_file) {
     fout = use_stdout ? ImgIoUtilSetBinaryMode(stdout)
-                      : fopen(out_file_name, "wb");
+                      : WFOPEN(out_file_name, "wb");
     if (fout == NULL) {
-      fprintf(stderr, "Error opening output file %s\n", out_file_name);
+      WFPRINTF(stderr, "Error opening output file %s\n",
+               (const W_CHAR*)out_file_name);
       return 0;
     }
   }

imageio/image_enc.h

@@ -79,7 +79,7 @@ int WebPWriteTIFF(FILE* fout, const struct WebPDecBuffer* const buffer);
 int WebPWriteAlphaPlane(FILE* fout, const struct WebPDecBuffer* const buffer);
 
 // Save as YUV samples as PGM format (using IMC4 layout).
-// See: http://www.fourcc.org/yuv.php#IMC4.
+// 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);
 

imageio/imageio_util.c

@@ -18,6 +18,7 @@
 #endif
 #include <stdlib.h>
 #include <string.h>
+#include "../examples/unicode.h"
 
 // -----------------------------------------------------------------------------
 // File I/O
@@ -73,7 +74,7 @@ int ImgIoUtilReadFile(const char* const file_name,
   uint8_t* file_data;
   size_t file_size;
   FILE* in;
-  const int from_stdin = (file_name == NULL) || !strcmp(file_name, "-");
+  const int from_stdin = (file_name == NULL) || !WSTRCMP(file_name, "-");
 
   if (from_stdin) return ImgIoUtilReadFromStdin(data, data_size);
 
@@ -81,29 +82,34 @@ int ImgIoUtilReadFile(const char* const file_name,
   *data = NULL;
   *data_size = 0;
 
-  in = fopen(file_name, "rb");
+  in = WFOPEN(file_name, "rb");
   if (in == NULL) {
-    fprintf(stderr, "cannot open input file '%s'\n", file_name);
+    WFPRINTF(stderr, "cannot open input file '%s'\n", (const W_CHAR*)file_name);
     return 0;
   }
   fseek(in, 0, SEEK_END);
   file_size = ftell(in);
+  if (file_size == (size_t)-1) {
+    fclose(in);
+    WFPRINTF(stderr, "error getting size of '%s'\n", (const W_CHAR*)file_name);
+    return 0;
+  }
   fseek(in, 0, SEEK_SET);
   // we allocate one extra byte for the \0 terminator
-  file_data = (uint8_t*)malloc(file_size + 1);
+  file_data = (uint8_t*)WebPMalloc(file_size + 1);
   if (file_data == NULL) {
     fclose(in);
-    fprintf(stderr, "memory allocation failure when reading file %s\n",
+    WFPRINTF(stderr, "memory allocation failure when reading file %s\n",
-            file_name);
+             (const W_CHAR*)file_name);
     return 0;
   }
   ok = (fread(file_data, file_size, 1, in) == 1);
   fclose(in);
 
   if (!ok) {
-    fprintf(stderr, "Could not read %d bytes of data from file %s\n",
+    WFPRINTF(stderr, "Could not read %d bytes of data from file %s\n",
-            (int)file_size, file_name);
+             (int)file_size, (const W_CHAR*)file_name);
-    free(file_data);
+    WebPFree(file_data);
     return 0;
   }
   file_data[file_size] = '\0';  // convenient 0-terminator
@@ -118,14 +124,15 @@ 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) || !strcmp(file_name, "-");
+  const int to_stdout = (file_name == NULL) || !WSTRCMP(file_name, "-");
 
   if (data == NULL) {
     return 0;
   }
-  out = to_stdout ? ImgIoUtilSetBinaryMode(stdout) : fopen(file_name, "wb");
+  out = to_stdout ? ImgIoUtilSetBinaryMode(stdout) : WFOPEN(file_name, "wb");
   if (out == NULL) {
-    fprintf(stderr, "Error! Cannot open output file '%s'\n", file_name);
+    WFPRINTF(stderr, "Error! Cannot open output file '%s'\n",
+             (const W_CHAR*)file_name);
     return 0;
   }
   ok = (fwrite(data, data_size, 1, out) == 1);
@@ -146,9 +153,11 @@ void ImgIoUtilCopyPlane(const uint8_t* src, int src_stride,
 
 // -----------------------------------------------------------------------------
 
-int ImgIoUtilCheckSizeArgumentsOverflow(uint64_t nmemb, size_t size) {
+int ImgIoUtilCheckSizeArgumentsOverflow(uint64_t stride, size_t height) {
-  const uint64_t total_size = nmemb * size;
+  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

imageio/imageio_util.h

@@ -29,7 +29,7 @@ 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 free().
+// 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.
@@ -54,8 +54,8 @@ void ImgIoUtilCopyPlane(const uint8_t* src, int src_stride,
 
 //------------------------------------------------------------------------------
 
-// Returns 0 in case of overflow of nmemb * size.
+// Returns 0 in case of overflow, memory over-allocation or excessive dimension.
-int ImgIoUtilCheckSizeArgumentsOverflow(uint64_t nmemb, size_t size);
+int ImgIoUtilCheckSizeArgumentsOverflow(uint64_t stride, size_t height);
 
 #ifdef __cplusplus
 }    // extern "C"

imageio/jpegdec.c

@@ -206,7 +206,18 @@ struct my_error_mgr {
 
 static void my_error_exit(j_common_ptr dinfo) {
   struct my_error_mgr* myerr = (struct my_error_mgr*)dinfo->err;
+  // The following code is disabled in fuzzing mode because:
+  // - the logs can be flooded due to invalid JPEG files
+  // - msg_code is wrongfully seen as uninitialized by msan when the libjpeg
+  //   dependency is not built with sanitizers enabled
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+  const int msg_code = myerr->pub.msg_code;
+  fprintf(stderr, "libjpeg error: ");
   dinfo->err->output_message(dinfo);
+  if (msg_code == JERR_INPUT_EOF || msg_code == JERR_FILE_READ) {
+    fprintf(stderr, "`jpegtran -copy all` MAY be able to process this file.\n");
+  }
+#endif
   longjmp(myerr->setjmp_buffer, 1);
 }
 
@@ -273,7 +284,7 @@ int ReadJPEG(const uint8_t* const data, size_t data_size,
   ctx.data = data;
   ctx.data_size = data_size;
 
-  memset((j_decompress_ptr)&dinfo, 0, sizeof(dinfo));   // for setjmp sanity
+  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;
 
@@ -335,7 +346,11 @@ int ReadJPEG(const uint8_t* const data, size_t data_size,
   pic->width = width;
   pic->height = height;
   ok = WebPPictureImportRGB(pic, rgb, (int)stride);
-  if (!ok) goto Error;
+  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);

imageio/pngdec.c

@@ -18,6 +18,9 @@
 #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>
@@ -27,11 +30,33 @@
 #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,
@@ -108,7 +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) },
@@ -171,11 +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) < \
+#if LOCAL_PNG_PREREQ(1,5)
-    ((1 << 8) | (5 << 0))
-      png_charp profile;
-#else  // >= libpng 1.5.0
       png_bytep profile;
+#else
+      png_charp profile;
 #endif
       png_uint_32 len;
 
@@ -211,7 +235,7 @@ int ReadPNG(const uint8_t* const data, size_t data_size,
   volatile png_infop end_info = NULL;
   PNGReadContext context = { NULL, 0, 0 };
   int color_type, bit_depth, interlaced;
-  int has_alpha;
+  int num_channels;
   int num_passes;
   int p;
   volatile int ok = 0;
@@ -224,7 +248,8 @@ int ReadPNG(const uint8_t* const data, size_t data_size,
   context.data = data;
   context.data_size = data_size;
 
-  png = png_create_read_struct(PNG_LIBPNG_VER_STRING, 0, 0, 0);
+  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);
@@ -234,6 +259,15 @@ int ReadPNG(const uint8_t* const data, size_t data_size,
     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);
@@ -259,9 +293,6 @@ int ReadPNG(const uint8_t* const data, size_t data_size,
   }
   if (png_get_valid(png, info, PNG_INFO_tRNS)) {
     png_set_tRNS_to_alpha(png);
-    has_alpha = 1;
-  } else {
-    has_alpha = !!(color_type & PNG_COLOR_MASK_ALPHA);
   }
 
   // Apply gamma correction if needed.
@@ -276,13 +307,16 @@ int ReadPNG(const uint8_t* const data, size_t data_size,
 
   if (!keep_alpha) {
     png_set_strip_alpha(png);
-    has_alpha = 0;
   }
 
   num_passes = png_set_interlace_handling(png);
   png_read_update_info(png, info);
 
-  stride = (int64_t)(has_alpha ? 4 : 3) * width * sizeof(*rgb);
+  num_channels = png_get_channels(png, info);
+  if (num_channels != 3 && num_channels != 4) {
+    goto Error;
+  }
+  stride = (int64_t)num_channels * width * sizeof(*rgb);
   if (stride != (int)stride ||
       !ImgIoUtilCheckSizeArgumentsOverflow(stride, height)) {
     goto Error;
@@ -307,8 +341,8 @@ int ReadPNG(const uint8_t* const data, size_t data_size,
 
   pic->width = (int)width;
   pic->height = (int)height;
-  ok = has_alpha ? WebPPictureImportRGBA(pic, rgb, (int)stride)
+  ok = (num_channels == 4) ? WebPPictureImportRGBA(pic, rgb, (int)stride)
-                 : WebPPictureImportRGB(pic, rgb, (int)stride);
+                           : WebPPictureImportRGB(pic, rgb, (int)stride);
 
   if (!ok) {
     goto Error;

imageio/pnmdec.c

@@ -20,21 +20,25 @@
 #include "webp/encode.h"
 #include "./imageio_util.h"
 
+#if defined(_MSC_VER) && _MSC_VER < 1900
+#define snprintf _snprintf
+#endif
+
 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 = 0x1f
+  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;   // 1, 3, 4
+  int bytes_per_px;
-  int depth;
+  int depth;          // 1 (grayscale), 2 (grayscale + alpha), 3 (rgb), 4 (rgba)
   int max_value;
   int type;           // 5, 6 or 7
   int seen_flags;
@@ -74,6 +78,7 @@ 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);
@@ -95,38 +100,43 @@ static size_t ReadPAMFields(PNMInfo* const info, size_t off) {
       info->seen_flags |= MAXVAL_FLAG;
       info->max_value = tmp;
     } else if (!strcmp(out, "TUPLTYPE RGB_ALPHA")) {
-      info->bytes_per_px = 4;
+      expected_depth = 4;
       info->seen_flags |= TUPLE_FLAG;
     } else if (!strcmp(out, "TUPLTYPE RGB")) {
-      info->bytes_per_px = 3;
+      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")) {
-      info->bytes_per_px = 1;
+      expected_depth = 1;
       info->seen_flags |= TUPLE_FLAG;
     } else if (!strcmp(out, "ENDHDR")) {
       break;
     } else {
       static const char kEllipsis[] = " ...";
+      const size_t kLen = strlen(kEllipsis) + 1;  // +1 = trailing \0
       int i;
-      if (out_size > 20) sprintf(out + 20 - strlen(kEllipsis), kEllipsis);
+      if (out_size > 20) snprintf(out + 20 - kLen, kLen, kEllipsis);
       for (i = 0; i < (int)strlen(out); ++i) {
-        if (!isprint(out[i])) 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 & TUPLE_FLAG)) {
+  if (!(info->seen_flags & ALL_NEEDED_FLAGS)) {
-    if (info->depth > 0 && info->depth <= 4 && info->depth != 2) {
+    fprintf(stderr, "PAM header error: missing tags%s%s%s%s\n",
-      info->seen_flags |= TUPLE_FLAG;
+            (info->seen_flags & WIDTH_FLAG) ? "" : " WIDTH",
-      info->bytes_per_px = info->depth * (info->max_value > 255 ? 2 : 1);
+            (info->seen_flags & HEIGHT_FLAG) ? "" : " HEIGHT",
-    } else {
+            (info->seen_flags & DEPTH_FLAG) ? "" : " DEPTH",
-      fprintf(stderr, "PAM: invalid bitdepth (%d).\n", info->depth);
+            (info->seen_flags & MAXVAL_FLAG) ? "" : " MAXVAL");
-      return 0;
+    return 0;
-    }
   }
-  if (info->seen_flags != ALL_NEEDED_FLAGS) {
+  if (expected_depth != -1 && info->depth != expected_depth) {
-    fprintf(stderr, "PAM: incomplete header.\n");
+    fprintf(stderr, "PAM header error: expected DEPTH %d but got DEPTH %d\n",
+            expected_depth, info->depth);
     return 0;
   }
   return off;
@@ -160,16 +170,15 @@ static size_t ReadHeader(PNMInfo* const info) {
 
     // finish initializing missing fields
     info->depth = (info->type == 5) ? 1 : 3;
-    info->bytes_per_px = info->depth * (info->max_value > 255 ? 2 : 1);
   }
   // perform some basic numerical validation
   if (info->width <= 0 || info->height <= 0 ||
       info->type <= 0 || info->type >= 9 ||
-      info->depth <= 0 || info->depth == 2 || info->depth > 4 ||
+      info->depth <= 0 || info->depth > 4 ||
-      info->bytes_per_px < info->depth ||
       info->max_value <= 0 || info->max_value >= 65536) {
     return 0;
   }
+  info->bytes_per_px = info->depth * (info->max_value > 255 ? 2 : 1);
   return off;
 }
 
@@ -178,7 +187,7 @@ int ReadPNM(const uint8_t* const data, size_t data_size,
             struct Metadata* const metadata) {
   int ok = 0;
   int i, j;
-  uint64_t stride, pixel_bytes;
+  uint64_t stride, pixel_bytes, sample_size, depth;
   uint8_t* rgb = NULL, *tmp_rgb;
   size_t offset;
   PNMInfo info;
@@ -209,8 +218,10 @@ int ReadPNM(const uint8_t* const data, size_t data_size,
     fprintf(stderr, "Truncated PNM file (P%d).\n", info.type);
     goto End;
   }
-  stride =
+  sample_size = (info.max_value > 255) ? 2 : 1;
-      (uint64_t)(info.bytes_per_px < 3 ? 3 : info.bytes_per_px) * info.width;
+  // 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;
@@ -219,30 +230,63 @@ int ReadPNM(const uint8_t* const data, size_t data_size,
   rgb = (uint8_t*)malloc((size_t)stride * info.height);
   if (rgb == NULL) goto End;
 
-  // Convert input
+  // 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) {
-    assert(offset + info.bytes_per_px * info.width <= data_size);
+    const uint8_t* in = data + offset;
-    if (info.depth == 1) {
-      // convert grayscale -> RGB
-      for (i = 0; i < info.width; ++i) {
-        const uint8_t v = data[offset + i];
-        tmp_rgb[3 * i + 0] = tmp_rgb[3 * i + 1] = tmp_rgb[3 * i + 2] = v;
-      }
-    } else if (info.depth == 3) {   // RGB
-      memcpy(tmp_rgb, data + offset, 3 * info.width * sizeof(*data));
-    } else if (info.depth == 4) {   // RGBA
-      memcpy(tmp_rgb, data + offset, 4 * info.width * sizeof(*data));
-    }
     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 = (info.depth == 4) ? WebPPictureImportRGBA(pic, rgb, (int)stride)
+  ok = (depth == 4) ? WebPPictureImportRGBA(pic, rgb, (int)stride)
-                         : WebPPictureImportRGB(pic, rgb, (int)stride);
+                    : WebPPictureImportRGB(pic, rgb, (int)stride);
   if (!ok) goto End;
 
   ok = 1;

imageio/tiffdec.c

@@ -46,7 +46,7 @@ static int ExtractMetadataFromTIFF(TIFF* const tif, Metadata* const metadata) {
         (MetadataPayload*)((uint8_t*)metadata +
                            kTIFFMetadataMap[i].storage_offset);
     void* tag_data;
-    uint32 tag_data_len;
+    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)) {
@@ -121,7 +121,6 @@ static tsize_t MyRead(thandle_t opaque, void* dst, tsize_t size) {
 // (we don't want to force a dependency to a libdspdec library).
 #define MFIX 24    // 24bit fixed-point arithmetic
 #define HALF ((1u << MFIX) >> 1)
-#define KINV_255 ((1u << MFIX) / 255u)
 
 static uint32_t Unmult(uint8_t x, uint32_t mult) {
   const uint32_t v = (x * mult + HALF) >> MFIX;
@@ -132,6 +131,9 @@ 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) {
@@ -154,7 +156,8 @@ int ReadTIFF(const uint8_t* const data, size_t data_size,
              Metadata* const metadata) {
   MyData my_data = { data, (toff_t)data_size, 0 };
   TIFF* tif;
-  uint32_t width, height;
+  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;
@@ -185,17 +188,40 @@ int ReadTIFF(const uint8_t* const data, size_t data_size,
     fprintf(stderr, "Error! Cannot retrieve TIFF samples-per-pixel info.\n");
     goto End;
   }
-  if (samples_per_px < 3 || samples_per_px > 4) goto End;  // not supported
+  if (!(samples_per_px == 1 || samples_per_px == 3 || samples_per_px == 4)) {
+    goto End;  // not supported
+  }
 
-  if (!(TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &width) &&
+  if (!(TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &image_width) &&
-        TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &height))) {
+        TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &image_height))) {
     fprintf(stderr, "Error! Cannot retrieve TIFF image dimensions.\n");
     goto End;
   }
-  if (!ImgIoUtilCheckSizeArgumentsOverflow((uint64_t)width * height,
+  stride = (uint64_t)image_width * sizeof(*raster);
-                                           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");
@@ -203,33 +229,32 @@ int ReadTIFF(const uint8_t* const data, size_t data_size,
   }
 
   // _Tiffmalloc uses a signed type for size.
-  alloc_size = (int64_t)((uint64_t)width * height * sizeof(*raster));
+  alloc_size = (int64_t)(stride * image_height);
   if (alloc_size < 0 || alloc_size != (tsize_t)alloc_size) goto End;
 
-  raster = (uint32*)_TIFFmalloc((tsize_t)alloc_size);
+  raster = (uint32_t*)_TIFFmalloc((tsize_t)alloc_size);
   if (raster != NULL) {
-    if (TIFFReadRGBAImageOriented(tif, width, height, raster,
+    if (TIFFReadRGBAImageOriented(tif, image_width, image_height, raster,
                                   ORIENTATION_TOPLEFT, 1)) {
-      const int stride = width * sizeof(*raster);
+      pic->width = image_width;
-      pic->width = width;
+      pic->height = image_height;
-      pic->height = height;
       // TIFF data is ABGR
 #ifdef WORDS_BIGENDIAN
-      TIFFSwabArrayOfLong(raster, width * height);
+      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 < height; ++y) {
+        for (y = 0; y < image_height; ++y) {
-          MultARGBRow(tmp, width);
+          MultARGBRow(tmp, image_width);
           tmp += stride;
         }
       }
       ok = keep_alpha
-         ? WebPPictureImportRGBA(pic, (const uint8_t*)raster, stride)
+         ? WebPPictureImportRGBA(pic, (const uint8_t*)raster, (int)stride)
-         : WebPPictureImportRGBX(pic, (const uint8_t*)raster, stride);
+         : WebPPictureImportRGBX(pic, (const uint8_t*)raster, (int)stride);
     }
     _TIFFfree(raster);
   } else {

imageio/webpdec.c

@@ -22,6 +22,7 @@
 #include "webp/decode.h"
 #include "webp/demux.h"
 #include "webp/encode.h"
+#include "../examples/unicode.h"
 #include "./imageio_util.h"
 #include "./metadata.h"
 
@@ -43,7 +44,7 @@ static void PrintAnimationWarning(const WebPDecoderConfig* const config) {
 }
 
 void PrintWebPError(const char* const in_file, int status) {
-  fprintf(stderr, "Decoding of %s failed.\n", in_file);
+  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]);
@@ -64,7 +65,7 @@ int LoadWebP(const char* const in_file,
 
   status = WebPGetFeatures(*data, *data_size, bitstream);
   if (status != VP8_STATUS_OK) {
-    free((void*)*data);
+    WebPFree((void*)*data);
     *data = NULL;
     *data_size = 0;
     PrintWebPError(in_file, status);
@@ -94,7 +95,7 @@ VP8StatusCode DecodeWebPIncremental(
   {
     WebPIDecoder* const idec = WebPIDecode(data, data_size, config);
     if (idec == NULL) {
-      fprintf(stderr, "Failed during WebPINewDecoder().\n");
+      fprintf(stderr, "Failed during WebPIDecode().\n");
       return VP8_STATUS_OUT_OF_MEMORY;
     } else {
       status = WebPIUpdate(idec, data, data_size);

imageio/wicdec.c

@@ -29,12 +29,14 @@
                          // 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 {                                                              \
@@ -85,7 +87,7 @@ WEBP_DEFINE_GUID(GUID_WICPixelFormat64bppRGBA_,
 
 static HRESULT OpenInputStream(const char* filename, IStream** stream) {
   HRESULT hr = S_OK;
-  if (!strcmp(filename, "-")) {
+  if (!WSTRCMP(filename, "-")) {
     const uint8_t* data = NULL;
     size_t data_size = 0;
     const int ok = ImgIoUtilReadFile(filename, &data, &data_size);
@@ -108,11 +110,12 @@ static HRESULT OpenInputStream(const char* filename, IStream** stream) {
       hr = E_FAIL;
     }
   } else {
-    IFS(SHCreateStreamOnFileA(filename, STGM_READ, stream));
+    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;
 }
@@ -131,7 +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;
@@ -267,10 +273,15 @@ 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;
@@ -295,9 +306,15 @@ int ReadPictureWithWIC(const char* const filename,
           factory, stream, NULL,
           WICDecodeMetadataCacheOnDemand, &decoder));
   IFS(IWICBitmapDecoder_GetFrameCount(decoder, &frame_count));
-  if (SUCCEEDED(hr) && frame_count == 0) {
+  if (SUCCEEDED(hr)) {
-    fprintf(stderr, "No frame found in input file.\n");
+    if (frame_count == 0) {
-    hr = E_FAIL;
+      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));

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

@@ -1,17 +1,21 @@
 #!/bin/bash
 #
-# This script generates 'WebP.framework' and 'WebPDecoder.framework'. An iOS
+# This script generates 'WebP.framework' and 'WebPDecoder.framework',
-# app can decode WebP images by including 'WebPDecoder.framework' and both
+# 'WebPDemux.framework' and 'WebPMux.framework'.
-# encode and decode WebP images by including 'WebP.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 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
 readonly SDK=$(xcodebuild -showsdks \
   | grep iphoneos | sort | tail -n 1 | awk '{print substr($NF, 9)}'
@@ -35,35 +39,59 @@ 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 SHARPYUVTARGETDIR="${TOPDIR}/SharpYuv.framework"
 readonly DEVELOPER=$(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%%.*} -gt 8 ]]; then
   EXTRA_CFLAGS="-fembed-bitcode"
-elif [[ ${SDK} < 6.0 ]]; then
+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} ${TARGETDIR} ${DECTARGETDIR}
+echo "Xcode Version: ${XCODE}"
-mkdir -p ${BUILDDIR} ${TARGETDIR}/Headers/ ${DECTARGETDIR}/Headers/
+echo "iOS SDK Version: ${SDK}"
+
+if [[ -e "${BUILDDIR}" || -e "${TARGETDIR}" || -e "${DECTARGETDIR}" \
+      || -e "${MUXTARGETDIR}" || -e "${DEMUXTARGETDIR}" \
+      || -e "${SHARPYUVTARGETDIR}" ]]; then
+  cat << EOF
+WARNING: The following directories will be deleted:
+WARNING:   ${BUILDDIR}
+WARNING:   ${TARGETDIR}
+WARNING:   ${DECTARGETDIR}
+WARNING:   ${MUXTARGETDIR}
+WARNING:   ${DEMUXTARGETDIR}
+WARNING:   ${SHARPYUVTARGETDIR}
+WARNING: The build will continue in 5 seconds...
+EOF
+  sleep 5
+fi
+rm -rf ${BUILDDIR} ${TARGETDIR} ${DECTARGETDIR} \
+    ${MUXTARGETDIR} ${DEMUXTARGETDIR} ${SHARPYUVTARGETDIR}
+mkdir -p ${BUILDDIR} ${TARGETDIR}/Headers/ ${DECTARGETDIR}/Headers/ \
+    ${MUXTARGETDIR}/Headers/ ${DEMUXTARGETDIR}/Headers/ \
+    ${SHARPYUVTARGETDIR}/Headers/
 
 if [[ ! -e ${SRCDIR}/configure ]]; then
   if ! (cd ${SRCDIR} && sh autogen.sh); then
-    cat <<EOT
+    cat << EOF
 Error creating configure script!
 This script requires the autoconf/automake and libtool to build. MacPorts can
 be used to obtain these:
-http://www.macports.org/install.php
+https://www.macports.org/install.php
-EOT
+EOF
     exit 1
   fi
 fi
@@ -97,7 +125,7 @@ for PLATFORM in ${PLATFORMS}; do
   SDKROOT="${PLATFORMSROOT}/"
   SDKROOT+="${PLATFORM}.platform/Developer/SDKs/${PLATFORM}${SDK}.sdk/"
   CFLAGS="-arch ${ARCH2:-${ARCH}} -pipe -isysroot ${SDKROOT} -O3 -DNDEBUG"
-  CFLAGS+=" -miphoneos-version-min=6.0 ${EXTRA_CFLAGS}"
+  CFLAGS+=" -miphoneos-version-min=${IOS_MIN_VERSION} ${EXTRA_CFLAGS}"
 
   set -x
   export PATH="${DEVROOT}/usr/bin:${OLDPATH}"
@@ -105,25 +133,46 @@ for PLATFORM in ${PLATFORMS}; do
     --build=$(${SRCDIR}/config.guess) \
     --disable-shared --enable-static \
     --enable-libwebpdecoder --enable-swap-16bit-csp \
+    --enable-libwebpmux \
     CFLAGS="${CFLAGS}"
   set +x
 
-  # run make only in the src/ directory to create libwebp.a/libwebpdecoder.a
+  # Build only the libraries, skip the examples.
-  cd src/
+  make V=0 -C sharpyuv install
-  make V=0
+  make V=0 -C src install
-  make install
 
   LIBLIST+=" ${ROOTDIR}/lib/libwebp.a"
   DECLIBLIST+=" ${ROOTDIR}/lib/libwebpdecoder.a"
+  MUXLIBLIST+=" ${ROOTDIR}/lib/libwebpmux.a"
+  DEMUXLIBLIST+=" ${ROOTDIR}/lib/libwebpdemux.a"
+  SHARPYUVLIBLIST+=" ${ROOTDIR}/lib/libsharpyuv.a"
 
   make clean
-  cd ..
 
   export PATH=${OLDPATH}
 done
 
+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 "SHARPYUVLIBLIST = ${SHARPYUVLIBLIST}"
+cp -a ${SRCDIR}/sharpyuv/{sharpyuv,sharpyuv_csp}.h \
+    ${SHARPYUVTARGETDIR}/Headers/
+${LIPO} -create ${SHARPYUVLIBLIST} -output ${SHARPYUVTARGETDIR}/SharpYuv
+
+echo  "SUCCESS"

makefile.unix

@@ -3,7 +3,8 @@
 # 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',
-# 'src/demux/libwebpdemux.a' and 'extras/libwebpextras.a'.
+# 'src/demux/libwebpdemux.a', 'extras/libwebpextras.a' and
+# 'sharpyuv/libsharpyuv.a'.
 #
 # To build the library and examples, use:
 #    make -f makefile.unix
@@ -36,18 +37,18 @@ else
 endif
 
 # SDL flags: use sdl-config if it exists
-SDL_CONFIG = $(shell sdl-config --version 2> /dev/null)
+SDL_CONFIG = $(shell sdl2-config --version 2> /dev/null)
 ifneq ($(SDL_CONFIG),)
-  SDL_LIBS = $(shell sdl-config --libs)
+  SDL_LIBS = $(shell sdl2-config --libs)
-  SDL_FLAGS = $(shell sdl-config --cflags)
+  SDL_FLAGS = $(shell sdl2-config --cflags)
 else
   # use best-guess
-  SDL_LIBS = -lSDL
+  SDL_LIBS = -lSDL2
   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"
@@ -89,12 +90,6 @@ EXTRA_FLAGS += -DWEBP_HAVE_SSE41
 src/dsp/%_sse41.o: EXTRA_FLAGS += -msse4.1
 endif
 
-# AVX2-specific flags:
-ifeq ($(HAVE_AVX2), 1)
-EXTRA_FLAGS += -DWEBP_HAVE_AVX2
-src/dsp/%_avx2.o: EXTRA_FLAGS += -mavx2
-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
@@ -124,9 +119,22 @@ 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_cpu.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_dec.o \
     src/dec/buffer_dec.o \
@@ -168,6 +176,7 @@ DSP_DEC_OBJS = \
     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 \
@@ -191,9 +200,9 @@ 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_avx2.o \
     src/dsp/enc_mips32.o \
     src/dsp/enc_mips_dsp_r2.o \
     src/dsp/enc_msa.o \
@@ -267,6 +276,7 @@ UTILS_DEC_OBJS = \
     src/utils/color_cache_utils.o \
     src/utils/filters_utils.o \
     src/utils/huffman_utils.o \
+    src/utils/palette.o \
     src/utils/quant_levels_dec_utils.o \
     src/utils/random_utils.o \
     src/utils/rescaler_utils.o \
@@ -281,13 +291,15 @@ UTILS_ENC_OBJS = \
 EXTRA_OBJS = \
     extras/extras.o \
     extras/quality_estimate.o \
+    extras/sharpyuv_risk_table.o \
 
 LIBWEBPDECODER_OBJS = $(DEC_OBJS) $(DSP_DEC_OBJS) $(UTILS_DEC_OBJS)
-LIBWEBP_OBJS = $(LIBWEBPDECODER_OBJS) $(ENC_OBJS) $(DSP_ENC_OBJS) \
+LIBWEBP_OBJS = $(LIBWEBPDECODER_OBJS) $(ENC_OBJS) \
-               $(UTILS_ENC_OBJS)
+               $(DSP_ENC_OBJS) $(UTILS_ENC_OBJS)
 LIBWEBPMUX_OBJS = $(MUX_OBJS)
 LIBWEBPDEMUX_OBJS = $(DEMUX_OBJS)
 LIBWEBPEXTRA_OBJS = $(EXTRA_OBJS)
+LIBSHARPYUV_OBJS = $(SHARPYUV_OBJS)
 
 HDRS_INSTALLED = \
     src/webp/decode.h \
@@ -297,6 +309,11 @@ HDRS_INSTALLED = \
     src/webp/mux_types.h \
     src/webp/types.h \
 
+SHARPYUV_HDRS_INSTALLED = \
+    sharpyuv/sharpyuv.h \
+    sharpyuv/sharpyuv_cpu.h \
+    sharpyuv/sharpyuv_csp.h \
+
 HDRS = \
     src/dec/alphai_dec.h \
     src/dec/common_dec.h \
@@ -305,6 +322,7 @@ HDRS = \
     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 \
@@ -327,6 +345,7 @@ HDRS = \
     src/utils/filters_utils.h \
     src/utils/huffman_utils.h \
     src/utils/huffman_encode_utils.h \
+    src/utils/palette.h \
     src/utils/quant_levels_utils.h \
     src/utils/quant_levels_dec_utils.h \
     src/utils/random_utils.h \
@@ -335,6 +354,7 @@ HDRS = \
     src/utils/utils.h \
     src/webp/format_constants.h \
     $(HDRS_INSTALLED) \
+    $(SHARPYUV_HDRS_INSTALLED) \
 
 OUT_LIBS = examples/libexample_util.a
 OUT_LIBS += imageio/libimageio_util.a
@@ -342,6 +362,7 @@ OUT_LIBS += imageio/libimagedec.a
 OUT_LIBS += imageio/libimageenc.a
 OUT_LIBS += src/libwebpdecoder.a
 OUT_LIBS += src/libwebp.a
+OUT_LIBS += sharpyuv/libsharpyuv.a
 EXTRA_LIB = extras/libwebpextras.a
 OUT_EXAMPLES = examples/cwebp examples/dwebp
 EXTRA_EXAMPLES = examples/gif2webp examples/vwebp examples/webpmux \
@@ -387,12 +408,13 @@ src/libwebpdecoder.a: $(LIBWEBPDECODER_OBJS)
 src/libwebp.a: $(LIBWEBP_OBJS)
 src/mux/libwebpmux.a: $(LIBWEBPMUX_OBJS)
 src/demux/libwebpdemux.a: $(LIBWEBPDEMUX_OBJS)
+sharpyuv/libsharpyuv.a: $(LIBSHARPYUV_OBJS)
 
 %.a:
 	$(AR) $(ARFLAGS) $@ $^
 
 examples/anim_diff: examples/anim_diff.o $(ANIM_UTIL_OBJS) $(GIFDEC_OBJS)
-examples/anim_dump: examples/anim_dump.o $(ANIM_UTIL_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 $(GIFDEC_OBJS)
@@ -404,43 +426,51 @@ 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: EXTRA_LIBS += $(GIF_LIBS)
+examples/anim_diff: sharpyuv/libsharpyuv.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/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: EXTRA_LIBS += $(GIF_LIBS) $(DWEBP_LIBS)
+examples/anim_dump: sharpyuv/libsharpyuv.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/cwebp: sharpyuv/libsharpyuv.a
+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: EXTRA_LIBS += $(DWEBP_LIBS)
+examples/dwebp: sharpyuv/libsharpyuv.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: EXTRA_LIBS += $(GIF_LIBS)
+examples/gif2webp: sharpyuv/libsharpyuv.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: imageio/libimageio_util.a src/libwebp.a
-examples/vwebp: EXTRA_LIBS += $(GL_LIBS)
+examples/vwebp: sharpyuv/libsharpyuv.a
+examples/vwebp: override EXTRA_LIBS += $(GL_LIBS)
 examples/vwebp: EXTRA_FLAGS += -DWEBP_HAVE_GL
 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: src/mux/libwebpmux.a
-examples/img2webp: EXTRA_LIBS += $(CWEBP_LIBS)
+examples/img2webp: src/libwebp.a
+examples/img2webp: sharpyuv/libsharpyuv.a
+examples/img2webp: override EXTRA_LIBS += $(CWEBP_LIBS)
 examples/webpinfo: examples/libexample_util.a imageio/libimageio_util.a
 examples/webpinfo: src/libwebpdecoder.a
 
@@ -449,18 +479,21 @@ 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: EXTRA_LIBS += $(CWEBP_LIBS)
+extras/get_disto: sharpyuv/libsharpyuv.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/webp_quality: sharpyuv/libsharpyuv.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: sharpyuv/libsharpyuv.a
 extras/vwebp_sdl: EXTRA_FLAGS += -DWEBP_HAVE_SDL $(SDL_FLAGS)
-extras/vwebp_sdl: EXTRA_LIBS += $(SDL_LIBS)
+extras/vwebp_sdl: override EXTRA_LIBS += $(SDL_LIBS)
 
 $(OUT_EXAMPLES) $(EXTRA_EXAMPLES) $(OTHER_EXAMPLES):
 	$(CC) -o $@ $^ $(LDFLAGS)
@@ -469,12 +502,15 @@ dist: DESTDIR := dist
 dist: OUT_EXAMPLES += $(EXTRA_EXAMPLES)
 dist: all
 	$(INSTALL) -m755 -d $(DESTDIR)/include/webp \
-	           $(DESTDIR)/bin $(DESTDIR)/doc $(DESTDIR)/lib
+	            $(DESTDIR)/include/webp/sharpyuv \
+	            $(DESTDIR)/bin $(DESTDIR)/doc $(DESTDIR)/lib
 	$(INSTALL) -m755 -s $(OUT_EXAMPLES) $(DESTDIR)/bin
 	$(INSTALL) -m644 $(HDRS_INSTALLED) $(DESTDIR)/include/webp
+	$(INSTALL) -m644 $(SHARPYUV_HDRS_INSTALLED) $(DESTDIR)/include/webp/sharpyuv
 	$(INSTALL) -m644 src/libwebp.a $(DESTDIR)/lib
 	$(INSTALL) -m644 src/demux/libwebpdemux.a $(DESTDIR)/lib
 	$(INSTALL) -m644 src/mux/libwebpmux.a $(DESTDIR)/lib
+	$(INSTALL) -m644 sharpyuv/libsharpyuv.a $(DESTDIR)/lib
 	umask 022; \
 	for m in man/[cdv]webp.1 man/gif2webp.1 man/webpmux.1 \
                  man/img2webp.1 man/webpinfo.1; do \
@@ -490,6 +526,7 @@ clean:
               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/*~ \

man/Makefile.am

@@ -1,10 +1,13 @@
 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

man/cwebp.1

@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH CWEBP 1 "January 20, 2017"
+.TH CWEBP 1 "September 17, 2024"
 .SH NAME
 cwebp \- compress an image file to a WebP file
 .SH SYNOPSIS
@@ -13,6 +13,7 @@ command.
 .PP
 \fBcwebp\fP compresses an image using the WebP format.
 Input format can be either PNG, JPEG, TIFF, WebP or raw Y'CbCr samples.
+Note: Animated PNG and WebP files are not supported.
 .SH OPTIONS
 The basic options are:
 .TP
@@ -41,10 +42,12 @@ the invisible pixel values (R/G/B or Y/U/V) will be preserved only if the
 \-exact option is used.
 .TP
 .BI \-near_lossless " int
-Use near\-lossless image preprocessing. This option adjusts pixel values
+Specify the level of near\-lossless image preprocessing. This option adjusts
-to help compressibility, but has minimal impact on the visual quality.
+pixel values to help compressibility, but has minimal impact on the visual
-It triggers lossless compression mode automatically.
+quality. It triggers lossless compression mode automatically. The range is 0
-Range is 0 (maximum preprocessing) to 100 (no preprocessing, the default).
+(maximum preprocessing) to 100 (no preprocessing, the default). The typical
+value is around 60. Note that lossy with \fB\-q 100\fP can at times yield
+better results.
 .TP
 .BI \-q " float
 Specify the compression factor for RGB channels between 0 and 100. The default
@@ -87,15 +90,17 @@ additional encoding possibilities and decide on the quality gain.
 Lower value can result in faster processing time at the expense of
 larger file size and lower compression quality.
 .TP
-.BI \-resize " width height
-Resize the source to a rectangle with size \fBwidth\fP x \fBheight\fP.
-If either (but not both) of the \fBwidth\fP or \fBheight\fP parameters is 0,
-the value will be calculated preserving the aspect\-ratio.
-.TP
 .BI \-crop " x_position y_position width height
 Crop the source to a rectangle with top\-left corner at coordinates
 (\fBx_position\fP, \fBy_position\fP) and size \fBwidth\fP x \fBheight\fP.
 This cropping area must be fully contained within the source rectangle.
+Note: the cropping is applied \fIbefore\fP any scaling.
+.TP
+.BI \-resize " width height
+Resize the source to a rectangle with size \fBwidth\fP x \fBheight\fP.
+If either (but not both) of the \fBwidth\fP or \fBheight\fP parameters is 0,
+the value will be calculated preserving the aspect\-ratio. Note: scaling
+is applied \fIafter\fP cropping.
 .TP
 .B \-mt
 Use multi\-threading for encoding, if possible.
@@ -130,7 +135,16 @@ are used, \fB\-size\fP value will prevail.
 Set a maximum number of passes to use during the dichotomy used by
 options \fB\-size\fP or \fB\-psnr\fP. Maximum value is 10, default is 1.
 If options \fB\-size\fP or \fB\-psnr\fP were used, but \fB\-pass\fP wasn't
-specified, a default value of '6' passes will be used.
+specified, a default value of '6' passes will be used. If \fB\-pass\fP is
+specified, but neither \fB-size\fP nor \fB-psnr\fP are, a target PSNR of 40dB
+will be used.
+.TP
+.BI \-qrange " int int
+Specifies the permissible interval for the quality factor. This is particularly
+useful when using multi-pass (\fB\-size\fP or \fB\-psnr\fP options).
+Default is 0 100.
+If the quality factor is outside this range, it will be clamped.
+If the minimum value must be less or equal to the maximum one.
 .TP
 .B \-af
 Turns auto\-filter on. This algorithm will spend additional time optimizing
@@ -166,8 +180,8 @@ Disable strong filtering (if filtering is being used thanks to the
 \fB\-f\fP option) and use simple filtering instead.
 .TP
 .B \-sharp_yuv
-Use more accurate and sharper RGB->YUV conversion if needed. Note that this
+Use more accurate and sharper RGB->YUV conversion. Note that this process is
-process is slower than the default 'fast' RGB->YUV conversion.
+slower than the default 'fast' RGB->YUV conversion.
 .TP
 .BI \-sns " int
 Specify the amplitude of the spatial noise shaping. Spatial noise shaping
@@ -190,7 +204,8 @@ In the VP8 format, the so\-called control partition has a limit of 512k and
 is used to store the following information: whether the macroblock is skipped,
 which segment it belongs to, whether it is coded as intra 4x4 or intra 16x16
 mode, and finally the prediction modes to use for each of the sub\-blocks.
-For a very large image, 512k only leaves room to few bits per 16x16 macroblock.
+For a very large image, 512k only leaves room for a few bits per 16x16
+macroblock.
 The absolute minimum is 4 bits per macroblock. Skip, segment, and mode
 information can use up almost all these 4 bits (although the case is unlikely),
 which is problematic for very large images. The partition_limit factor controls
@@ -199,7 +214,8 @@ useful in case the 512k limit is reached and the following message is displayed:
 \fIError code: 6 (PARTITION0_OVERFLOW: Partition #0 is too big to fit 512k)\fP.
 If using \fB\-partition_limit\fP is not enough to meet the 512k constraint, one
 should use less segments in order to save more header bits per macroblock.
-See the \fB\-segments\fP option.
+See the \fB\-segments\fP option. Note the \fB-m\fP and \fB-q\fP options also
+influence the encoder's decisions and ability to hit this limit.
 
 .SS LOGGING OPTIONS
 These options control the level of output:
@@ -212,7 +228,7 @@ Compute and report average PSNR (Peak\-Signal\-To\-Noise ratio).
 .TP
 .B \-print_ssim
 Compute and report average SSIM (structural similarity
-metric, see http://en.wikipedia.org/wiki/SSIM for additional details).
+metric, see https://en.wikipedia.org/wiki/SSIM for additional details).
 .TP
 .B \-print_lsim
 Compute and report local similarity metric (sum of lowest error amongst the
@@ -283,12 +299,12 @@ Note: each input format may not support all combinations.
 .B \-noasm
 Disable all assembly optimizations.
 
-.SH BUGS
+.SH EXIT STATUS
-Please report all bugs to the issue tracker:
+If there were no problems during execution, \fBcwebp\fP exits with the value of
-https://bugs.chromium.org/p/webp
+the C constant \fBEXIT_SUCCESS\fP. This is usually zero.
-.br
+.PP
-Patches welcome! See this page to get started:
+If an error occurs, \fBcwebp\fP exits with the value of the C constant
-http://www.webmproject.org/code/contribute/submitting\-patches/
+\fBEXIT_FAILURE\fP. This is usually one.
 
 .SH EXAMPLES
 cwebp \-q 50 -lossless picture.png \-o picture_lossless.webp
@@ -308,9 +324,16 @@ https://chromium.googlesource.com/webm/libwebp
 This manual page was written by Pascal Massimino <pascal.massimino@gmail.com>,
 for the Debian project (and may be used by others).
 
+.SH REPORTING BUGS
+Please report all bugs to the issue tracker:
+https://issues.webmproject.org
+.br
+Patches welcome! See this page to get started:
+https://www.webmproject.org/code/contribute/submitting\-patches/
+
 .SH SEE ALSO
 .BR dwebp (1),
 .BR gif2webp (1)
 .br
-Please refer to http://developers.google.com/speed/webp/ for additional
+Please refer to https://developers.google.com/speed/webp/ for additional
 information.

man/dwebp.1

@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH DWEBP 1 "June 23, 2016"
+.TH DWEBP 1 "July 18, 2024"
 .SH NAME
 dwebp \- decompress a WebP file to an image file
 .SH SYNOPSIS
@@ -12,6 +12,7 @@ This manual page documents the
 command.
 .PP
 \fBdwebp\fP decompresses WebP files into PNG, PAM, PPM or PGM images.
+Note: Animated WebP files are not supported.
 .SH OPTIONS
 The basic options are:
 .TP
@@ -107,12 +108,12 @@ Print extra information (decoding time in particular).
 .B \-noasm
 Disable all assembly optimizations.
 
-.SH BUGS
+.SH EXIT STATUS
-Please report all bugs to the issue tracker:
+If there were no problems during execution, \fBdwebp\fP exits with the value of
-https://bugs.chromium.org/p/webp
+the C constant \fBEXIT_SUCCESS\fP. This is usually zero.
-.br
+.PP
-Patches welcome! See this page to get started:
+If an error occurs, \fBdwebp\fP exits with the value of the C constant
-http://www.webmproject.org/code/contribute/submitting-patches/
+\fBEXIT_FAILURE\fP. This is usually one.
 
 .SH EXAMPLES
 dwebp picture.webp \-o output.png
@@ -132,12 +133,19 @@ https://chromium.googlesource.com/webm/libwebp
 This manual page was written by Pascal Massimino <pascal.massimino@gmail.com>,
 for the Debian project (and may be used by others).
 
+.SH REPORTING BUGS
+Please report all bugs to the issue tracker:
+https://issues.webmproject.org
+.br
+Patches welcome! See this page to get started:
+https://www.webmproject.org/code/contribute/submitting\-patches/
+
 .SH SEE ALSO
 .BR cwebp (1),
 .BR gif2webp (1),
 .BR webpmux (1)
 .br
-Please refer to http://developers.google.com/speed/webp/ for additional
+Please refer to https://developers.google.com/speed/webp/ for additional
 information.
 .SS Output file format details
 PAM: http://netpbm.sourceforge.net/doc/pam.html

man/gif2webp.1

@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH GIF2WEBP 1 "January 25, 2018"
+.TH GIF2WEBP 1 "July 18, 2024"
 .SH NAME
 gif2webp \- Convert a GIF image to WebP
 .SH SYNOPSIS
@@ -62,9 +62,9 @@ larger file size and lower compression quality.
 .TP
 .BI \-min_size
 Encode image to achieve smallest size. This disables key frame insertion and
-picks the dispose method resulting in smallest output for each frame. It uses
+picks the dispose method resulting in the smallest output for each frame. It
-lossless compression by default, but can be combined with \-q, \-m, \-lossy or
+uses lossless compression by default, but can be combined with \-q, \-m,
-\-mixed options.
+\-lossy or \-mixed options.
 .TP
 .BI \-kmin " int
 .TP
@@ -126,12 +126,12 @@ Print extra information.
 .B \-quiet
 Do not print anything.
 
-.SH BUGS
+.SH EXIT STATUS
-Please report all bugs to the issue tracker:
+If there were no problems during execution, \fBgif2webp\fP exits with the value
-https://bugs.chromium.org/p/webp
+of the C constant \fBEXIT_SUCCESS\fP. This is usually zero.
-.br
+.PP
-Patches welcome! See this page to get started:
+If an error occurs, \fBgif2webp\fP exits with the value of the C constant
-http://www.webmproject.org/code/contribute/submitting-patches/
+\fBEXIT_FAILURE\fP. This is usually one.
 
 .SH EXAMPLES
 gif2webp picture.gif \-o picture.webp
@@ -155,10 +155,17 @@ https://chromium.googlesource.com/webm/libwebp
 This manual page was written by Urvang Joshi <urvang@google.com>, for the
 Debian project (and may be used by others).
 
+.SH REPORTING BUGS
+Please report all bugs to the issue tracker:
+https://issues.webmproject.org
+.br
+Patches welcome! See this page to get started:
+https://www.webmproject.org/code/contribute/submitting\-patches/
+
 .SH SEE ALSO
 .BR cwebp (1),
 .BR dwebp (1),
 .BR webpmux (1)
 .br
-Please refer to http://developers.google.com/speed/webp/ for additional
+Please refer to https://developers.google.com/speed/webp/ for additional
 information.

man/img2webp.1

@@ -1,10 +1,10 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH IMG2WEBP 1 "April 3, 2018"
+.TH IMG2WEBP 1 "September 17, 2024"
 .SH NAME
 img2webp \- create animated WebP file from a sequence of input images.
 .SH SYNOPSIS
 .B img2webp
-[file_level_options] [files] [per_frame_options...]
+[file_options] [[frame_options] frame_file]... [\-o webp_file]
 .br
 .B img2webp argument_file_name
 .br
@@ -16,8 +16,8 @@ command.
 \fBimg2webp\fP compresses a sequence of images using the animated WebP format.
 Input images can either be PNG, JPEG, TIFF or WebP.
 If a single file name (not starting with the character '\-') is supplied as
-the argument, the command line argument are actually tokenized from this file.
+the argument, the command line arguments are actually tokenized from this file.
-This allows for easy scripting or using large number of arguments.
+This allows for easy scripting or using a large number of arguments.
 .SH FILE-LEVEL OPTIONS
 The file-level options are applied at the beginning of the compression process,
 before the input frames are read.
@@ -27,7 +27,7 @@ Specify the name of the output WebP file.
 .TP
 .BI \-min_size
 Encode images to achieve smallest size. This disables key frame insertion and
-picks the parameters resulting in smallest output for each frame. It uses
+picks the parameters resulting in the smallest output for each frame. It uses
 lossless compression by default, but can be combined with \-q, \-m, \-lossy or
 \-mixed options.
 .TP
@@ -44,6 +44,18 @@ Mixed compression mode: optimize compression of the image by picking either
 lossy or lossless compression for each frame heuristically. This global
 option disables the local option \fB-lossy\fP and \fB-lossless\fP .
 .TP
+.BI \-near_lossless " int
+Specify the level of near\-lossless image preprocessing. This option adjusts
+pixel values to help compressibility, but has minimal impact on the visual
+quality. It triggers lossless compression mode automatically. The range is 0
+(maximum preprocessing) to 100 (no preprocessing, the default). The typical
+value is around 60. Note that lossy with \fB\-q 100\fP can at times yield
+better results.
+.TP
+.B \-sharp_yuv
+Use more accurate and sharper RGB->YUV conversion. Note that this process is
+slower than the default 'fast' RGB->YUV conversion.
+.TP
 .BI \-loop " int
 Specifies the number of times the animation should loop. Using '0'
 means 'loop indefinitely'.
@@ -76,18 +88,23 @@ Specify the compression factor between 0 and 100. The default is 75.
 Specify the compression method to use. This parameter controls the
 trade off between encoding speed and the compressed file size and quality.
 Possible values range from 0 to 6. Default value is 4.
+.TP
+.B \-exact, \-noexact
+Preserve or alter RGB values in transparent area. The default is
+\fB-noexact\fP, to help compressibility. Note \fB\-noexact\fP may cause
+artifacts in frames compressed with \fB\-lossy\fP.
+
+.SH EXIT STATUS
+If there were no problems during execution, \fBimg2webp\fP exits with the value
+of the C constant \fBEXIT_SUCCESS\fP. This is usually zero.
+.PP
+If an error occurs, \fBimg2webp\fP exits with the value of the C constant
+\fBEXIT_FAILURE\fP. This is usually one.
 
 .SH EXAMPLE
 img2webp -loop 2 in0.png -lossy in1.jpg -d 80 in2.tiff -o out.webp
 .br
 
-.SH BUGS
-Please report all bugs to the issue tracker:
-https://bugs.chromium.org/p/webp
-.br
-Patches welcome! See this page to get started:
-http://www.webmproject.org/code/contribute/submitting\-patches/
-
 .SH AUTHORS
 \fBimg2webp\fP is a part of libwebp and was written by the WebP team.
 .br
@@ -97,9 +114,16 @@ https://chromium.googlesource.com/webm/libwebp
 This manual page was written by Pascal Massimino <pascal.massimino@gmail.com>,
 for the Debian project (and may be used by others).
 
+.SH REPORTING BUGS
+Please report all bugs to the issue tracker:
+https://issues.webmproject.org
+.br
+Patches welcome! See this page to get started:
+https://www.webmproject.org/code/contribute/submitting\-patches/
+
 .SH SEE ALSO
 .BR webpmux (1),
 .BR gif2webp (1)
 .br
-Please refer to http://developers.google.com/speed/webp/ for additional
+Please refer to https://developers.google.com/speed/webp/ for additional
 information.

man/vwebp.1

@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH VWEBP 1 "November 25, 2016"
+.TH VWEBP 1 "July 18, 2024"
 .SH NAME
 vwebp \- decompress a WebP file and display it in a window
 .SH SYNOPSIS
@@ -38,6 +38,10 @@ It helps by smoothing gradients and avoiding banding artifacts. Default: 50.
 By default, quantized transparency planes are dithered during decompression,
 to smooth the gradients. This flag will prevent this dithering.
 .TP
+.B \-usebgcolor
+Fill transparent areas with the bitstream's own background color instead of
+checkerboard only. Default is white for non-animated images.
+.TP
 .B \-mt
 Use multi-threading for decoding, if possible.
 .TP
@@ -56,6 +60,9 @@ the data will be read from \fIstdin\fP instead of a file.
 .B 'c'
 Toggle use of color profile.
 .TP
+.B 'b'
+Toggle display of background color.
+.TP
 .B 'i'
 Overlay file information.
 .TP
@@ -65,12 +72,12 @@ Disable blending and disposal process, for debugging purposes.
 .B 'q' / 'Q' / ESC
 Quit.
 
-.SH BUGS
+.SH EXIT STATUS
-Please report all bugs to the issue tracker:
+If there were no problems during execution, \fBvwebp\fP exits with the value of
-https://bugs.chromium.org/p/webp
+the C constant \fBEXIT_SUCCESS\fP. This is usually zero.
-.br
+.PP
-Patches welcome! See this page to get started:
+If an error occurs, \fBvwebp\fP exits with the value of the C constant
-http://www.webmproject.org/code/contribute/submitting-patches/
+\fBEXIT_FAILURE\fP. This is usually one.
 
 .SH EXAMPLES
 vwebp picture.webp
@@ -87,8 +94,15 @@ https://chromium.googlesource.com/webm/libwebp
 .PP
 This manual page was written for the Debian project (and may be used by others).
 
+.SH REPORTING BUGS
+Please report all bugs to the issue tracker:
+https://issues.webmproject.org
+.br
+Patches welcome! See this page to get started:
+https://www.webmproject.org/code/contribute/submitting\-patches/
+
 .SH SEE ALSO
 .BR dwebp (1)
 .br
-Please refer to http://developers.google.com/speed/webp/ for additional
+Please refer to https://developers.google.com/speed/webp/ for additional
 information.

man/webpinfo.1

@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH WEBPINFO 1 "November 24, 2017"
+.TH WEBPINFO 1 "July 18, 2024"
 .SH NAME
 webpinfo \- print out the chunk level structure of WebP files
 along with basic integrity checks.
@@ -47,12 +47,12 @@ Detailed usage instructions.
 Input files in WebP format. Input files must come last, following
 options (if any). There can be multiple input files.
 
-.SH BUGS
+.SH EXIT STATUS
-Please report all bugs to the issue tracker:
+If there were no problems during execution, \fBwebpinfo\fP exits with the value
-https://bugs.chromium.org/p/webp
+of the C constant \fBEXIT_SUCCESS\fP. This is usually zero.
-.br
+.PP
-Patches welcome! See this page to get started:
+If an error occurs, \fBwebpinfo\fP exits with the value of the C constant
-http://www.webmproject.org/code/contribute/submitting\-patches/
+\fBEXIT_FAILURE\fP. This is usually one.
 
 .SH EXAMPLES
 .br
@@ -73,8 +73,15 @@ https://chromium.googlesource.com/webm/libwebp
 This manual page was written by Hui Su <huisu@google.com>,
 for the Debian project (and may be used by others).
 
+.SH REPORTING BUGS
+Please report all bugs to the issue tracker:
+https://issues.webmproject.org
+.br
+Patches welcome! See this page to get started:
+https://www.webmproject.org/code/contribute/submitting\-patches/
+
 .SH SEE ALSO
 .BR webpmux (1)
 .br
-Please refer to http://developers.google.com/speed/webp/ for additional
+Please refer to https://developers.google.com/speed/webp/ for additional
 information.

man/webpmux.1

@@ -1,5 +1,5 @@
 .\"                                      Hey, EMACS: -*- nroff -*-
-.TH WEBPMUX 1 "December 1, 2017"
+.TH WEBPMUX 1 "July 18, 2024"
 .SH NAME
 webpmux \- create animated WebP files from non\-animated WebP images, extract
 frames from animated WebP images, and manage XMP/EXIF metadata and ICC profile.
@@ -58,8 +58,8 @@ command.
 \fBwebpmux\fP can be used to create/extract from animated WebP files, as well as
 to add/extract/strip XMP/EXIF metadata and ICC profile.
 If a single file name (not starting with the character '\-') is supplied as
-the argument, the command line argument are actually tokenized from this file.
+the argument, the command line arguments are actually tokenized from this file.
-This allows for easy scripting or using large number of arguments.
+This allows for easy scripting or using a large number of arguments.
 .SH OPTIONS
 .SS GET_OPTIONS (\-get):
 .TP
@@ -77,6 +77,17 @@ Get nth frame from an animated image. (n = 0 has a special meaning: last frame).
 
 .SS SET_OPTIONS (\-set)
 .TP
+.BI loop " loop_count
+Set loop count on an animated file.
+.P
+Where: 'loop_count' must be in range [0, 65535].
+.TP
+.BI bgcolor " A,R,G,B
+Set the background color of the canvas on an animated file.
+.P
+where: 'A', 'R', 'G' and 'B' are integers in the range 0 to 255 specifying the
+Alpha, Red, Green and Blue component values respectively.
+.TP
 .BI icc " file.icc
 Set ICC profile.
 .P
@@ -175,12 +186,12 @@ Output file in WebP format.
 .TP
 The nature of EXIF, XMP and ICC data is not checked and is assumed to be valid.
 
-.SH BUGS
+.SH EXIT STATUS
-Please report all bugs to the issue tracker:
+If there were no problems during execution, \fBwebpmux\fP exits with the value
-https://bugs.chromium.org/p/webp
+of the C constant \fBEXIT_SUCCESS\fP. This is usually zero.
-.br
+.PP
-Patches welcome! See this page to get started:
+If an error occurs, \fBwebpmux\fP exits with the value of the C constant
-http://www.webmproject.org/code/contribute/submitting\-patches/
+\fBEXIT_FAILURE\fP. This is usually one.
 
 .SH EXAMPLES
 .P
@@ -251,10 +262,17 @@ https://chromium.googlesource.com/webm/libwebp
 This manual page was written by Vikas Arora <vikaas.arora@gmail.com>,
 for the Debian project (and may be used by others).
 
+.SH REPORTING BUGS
+Please report all bugs to the issue tracker:
+https://issues.webmproject.org
+.br
+Patches welcome! See this page to get started:
+https://www.webmproject.org/code/contribute/submitting\-patches/
+
 .SH SEE ALSO
 .BR cwebp (1),
 .BR dwebp (1),
 .BR gif2webp (1)
 .br
-Please refer to http://developers.google.com/speed/webp/ for additional
+Please refer to https://developers.google.com/speed/webp/ for additional
 information.

sharpyuv/Makefile.am

@@ -0,0 +1,41 @@
+AM_CPPFLAGS += -I$(top_builddir) -I$(top_srcdir)
+AM_CPPFLAGS += -I$(top_builddir)/src -I$(top_srcdir)/src
+
+lib_LTLIBRARIES = libsharpyuv.la
+
+noinst_LTLIBRARIES =
+noinst_LTLIBRARIES += libsharpyuv_sse2.la
+noinst_LTLIBRARIES += libsharpyuv_neon.la
+
+libsharpyuvinclude_HEADERS =
+libsharpyuvinclude_HEADERS += sharpyuv.h
+libsharpyuvinclude_HEADERS += sharpyuv_csp.h
+noinst_HEADERS =
+noinst_HEADERS += ../src/dsp/cpu.c
+noinst_HEADERS += ../src/dsp/cpu.h
+noinst_HEADERS += ../src/webp/types.h
+
+libsharpyuv_sse2_la_SOURCES =
+libsharpyuv_sse2_la_SOURCES += sharpyuv_sse2.c
+libsharpyuv_sse2_la_CPPFLAGS = $(libsharpyuv_la_CPPFLAGS)
+libsharpyuv_sse2_la_CFLAGS = $(AM_CFLAGS) $(SSE2_FLAGS)
+
+libsharpyuv_neon_la_SOURCES =
+libsharpyuv_neon_la_SOURCES += sharpyuv_neon.c
+libsharpyuv_neon_la_CPPFLAGS = $(libsharpyuv_la_CPPFLAGS)
+libsharpyuv_neon_la_CFLAGS = $(AM_CFLAGS) $(NEON_FLAGS)
+
+libsharpyuv_la_SOURCES =
+libsharpyuv_la_SOURCES += sharpyuv_cpu.c sharpyuv_cpu.h
+libsharpyuv_la_SOURCES += sharpyuv_csp.c sharpyuv_csp.h
+libsharpyuv_la_SOURCES += sharpyuv_dsp.c sharpyuv_dsp.h
+libsharpyuv_la_SOURCES += sharpyuv_gamma.c sharpyuv_gamma.h
+libsharpyuv_la_SOURCES += sharpyuv.c sharpyuv.h
+
+libsharpyuv_la_CPPFLAGS = $(AM_CPPFLAGS)
+libsharpyuv_la_LDFLAGS = -no-undefined -version-info 1:0:1 -lm
+libsharpyuv_la_LIBADD =
+libsharpyuv_la_LIBADD += libsharpyuv_sse2.la
+libsharpyuv_la_LIBADD += libsharpyuv_neon.la
+libsharpyuvincludedir = $(includedir)/webp/sharpyuv
+pkgconfig_DATA = libsharpyuv.pc

sharpyuv/libsharpyuv.pc.in

@@ -0,0 +1,11 @@
+prefix=@prefix@
+exec_prefix=@exec_prefix@
+libdir=@libdir@
+includedir=@includedir@/webp
+
+Name: libsharpyuv
+Description: Library for sharp RGB to YUV conversion
+Version: @PACKAGE_VERSION@
+Cflags: -I${includedir}
+Libs: -L${libdir} -l@webp_libname_prefix@sharpyuv
+Libs.private: -lm @PTHREAD_CFLAGS@ @PTHREAD_LIBS@

sharpyuv/libsharpyuv.rc

@@ -0,0 +1,41 @@
+#define APSTUDIO_READONLY_SYMBOLS
+#include "winres.h"
+#undef APSTUDIO_READONLY_SYMBOLS
+
+#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_ENU)
+LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
+
+VS_VERSION_INFO VERSIONINFO
+ FILEVERSION 0,0,4,0
+ PRODUCTVERSION 0,0,4,0
+ FILEFLAGSMASK 0x3fL
+#ifdef _DEBUG
+ FILEFLAGS 0x1L
+#else
+ FILEFLAGS 0x0L
+#endif
+ FILEOS 0x40004L
+ FILETYPE 0x2L
+ FILESUBTYPE 0x0L
+BEGIN
+    BLOCK "StringFileInfo"
+    BEGIN
+        BLOCK "040904b0"
+        BEGIN
+            VALUE "CompanyName", "Google, Inc."
+            VALUE "FileDescription", "libsharpyuv DLL"
+            VALUE "FileVersion", "0.4.0"
+            VALUE "InternalName", "libsharpyuv.dll"
+            VALUE "LegalCopyright", "Copyright (C) 2024"
+            VALUE "OriginalFilename", "libsharpyuv.dll"
+            VALUE "ProductName", "SharpYuv Library"
+            VALUE "ProductVersion", "0.4.0"
+        END
+    END
+    BLOCK "VarFileInfo"
+    BEGIN
+        VALUE "Translation", 0x409, 1200
+    END
+END
+
+#endif    // English (United States) resources

sharpyuv/sharpyuv.c

@@ -0,0 +1,575 @@
+// Copyright 2022 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.
+// -----------------------------------------------------------------------------
+//
+// Sharp RGB to YUV conversion.
+//
+// Author: Skal (pascal.massimino@gmail.com)
+
+#include "sharpyuv/sharpyuv.h"
+
+#include <assert.h>
+#include <limits.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "src/webp/types.h"
+#include "sharpyuv/sharpyuv_cpu.h"
+#include "sharpyuv/sharpyuv_dsp.h"
+#include "sharpyuv/sharpyuv_gamma.h"
+
+//------------------------------------------------------------------------------
+
+int SharpYuvGetVersion(void) {
+  return SHARPYUV_VERSION;
+}
+
+//------------------------------------------------------------------------------
+// Sharp RGB->YUV conversion
+
+static const int kNumIterations = 4;
+
+#define YUV_FIX 16  // fixed-point precision for RGB->YUV
+static const int kYuvHalf = 1 << (YUV_FIX - 1);
+
+// Max bit depth so that intermediate calculations fit in 16 bits.
+static const int kMaxBitDepth = 14;
+
+// Returns the precision shift to use based on the input rgb_bit_depth.
+static int GetPrecisionShift(int rgb_bit_depth) {
+  // Try to add 2 bits of precision if it fits in kMaxBitDepth. Otherwise remove
+  // bits if needed.
+  return ((rgb_bit_depth + 2) <= kMaxBitDepth) ? 2
+                                               : (kMaxBitDepth - rgb_bit_depth);
+}
+
+typedef int16_t fixed_t;      // signed type with extra precision for UV
+typedef uint16_t fixed_y_t;   // unsigned type with extra precision for W
+
+//------------------------------------------------------------------------------
+
+static uint8_t clip_8b(fixed_t v) {
+  return (!(v & ~0xff)) ? (uint8_t)v : (v < 0) ? 0u : 255u;
+}
+
+static uint16_t clip(fixed_t v, int max) {
+  return (v < 0) ? 0 : (v > max) ? max : (uint16_t)v;
+}
+
+static fixed_y_t clip_bit_depth(int y, int bit_depth) {
+  const int max = (1 << bit_depth) - 1;
+  return (!(y & ~max)) ? (fixed_y_t)y : (y < 0) ? 0 : max;
+}
+
+//------------------------------------------------------------------------------
+
+static int RGBToGray(int64_t r, int64_t g, int64_t b) {
+  const int64_t luma = 13933 * r + 46871 * g + 4732 * b + kYuvHalf;
+  return (int)(luma >> YUV_FIX);
+}
+
+static uint32_t ScaleDown(uint16_t a, uint16_t b, uint16_t c, uint16_t d,
+                          int rgb_bit_depth,
+                          SharpYuvTransferFunctionType transfer_type) {
+  const int bit_depth = rgb_bit_depth + GetPrecisionShift(rgb_bit_depth);
+  const uint32_t A = SharpYuvGammaToLinear(a, bit_depth, transfer_type);
+  const uint32_t B = SharpYuvGammaToLinear(b, bit_depth, transfer_type);
+  const uint32_t C = SharpYuvGammaToLinear(c, bit_depth, transfer_type);
+  const uint32_t D = SharpYuvGammaToLinear(d, bit_depth, transfer_type);
+  return SharpYuvLinearToGamma((A + B + C + D + 2) >> 2, bit_depth,
+                               transfer_type);
+}
+
+static WEBP_INLINE void UpdateW(const fixed_y_t* src, fixed_y_t* dst, int w,
+                                int rgb_bit_depth,
+                                SharpYuvTransferFunctionType transfer_type) {
+  const int bit_depth = rgb_bit_depth + GetPrecisionShift(rgb_bit_depth);
+  int i = 0;
+  do {
+    const uint32_t R =
+        SharpYuvGammaToLinear(src[0 * w + i], bit_depth, transfer_type);
+    const uint32_t G =
+        SharpYuvGammaToLinear(src[1 * w + i], bit_depth, transfer_type);
+    const uint32_t B =
+        SharpYuvGammaToLinear(src[2 * w + i], bit_depth, transfer_type);
+    const uint32_t Y = RGBToGray(R, G, B);
+    dst[i] = (fixed_y_t)SharpYuvLinearToGamma(Y, bit_depth, transfer_type);
+  } while (++i < w);
+}
+
+static void UpdateChroma(const fixed_y_t* src1, const fixed_y_t* src2,
+                         fixed_t* dst, int uv_w, int rgb_bit_depth,
+                         SharpYuvTransferFunctionType transfer_type) {
+  int i = 0;
+  do {
+    const int r =
+        ScaleDown(src1[0 * uv_w + 0], src1[0 * uv_w + 1], src2[0 * uv_w + 0],
+                  src2[0 * uv_w + 1], rgb_bit_depth, transfer_type);
+    const int g =
+        ScaleDown(src1[2 * uv_w + 0], src1[2 * uv_w + 1], src2[2 * uv_w + 0],
+                  src2[2 * uv_w + 1], rgb_bit_depth, transfer_type);
+    const int b =
+        ScaleDown(src1[4 * uv_w + 0], src1[4 * uv_w + 1], src2[4 * uv_w + 0],
+                  src2[4 * uv_w + 1], rgb_bit_depth, transfer_type);
+    const int W = RGBToGray(r, g, b);
+    dst[0 * uv_w] = (fixed_t)(r - W);
+    dst[1 * uv_w] = (fixed_t)(g - W);
+    dst[2 * uv_w] = (fixed_t)(b - W);
+    dst  += 1;
+    src1 += 2;
+    src2 += 2;
+  } while (++i < uv_w);
+}
+
+static void StoreGray(const fixed_y_t* rgb, fixed_y_t* y, int w) {
+  int i = 0;
+  assert(w > 0);
+  do {
+    y[i] = RGBToGray(rgb[0 * w + i], rgb[1 * w + i], rgb[2 * w + i]);
+  } while (++i < w);
+}
+
+//------------------------------------------------------------------------------
+
+static WEBP_INLINE fixed_y_t Filter2(int A, int B, int W0, int bit_depth) {
+  const int v0 = (A * 3 + B + 2) >> 2;
+  return clip_bit_depth(v0 + W0, bit_depth);
+}
+
+//------------------------------------------------------------------------------
+
+static WEBP_INLINE int Shift(int v, int shift) {
+  return (shift >= 0) ? (v << shift) : (v >> -shift);
+}
+
+static void ImportOneRow(const uint8_t* const r_ptr,
+                         const uint8_t* const g_ptr,
+                         const uint8_t* const b_ptr,
+                         int rgb_step,
+                         int rgb_bit_depth,
+                         int pic_width,
+                         fixed_y_t* const dst) {
+  // Convert the rgb_step from a number of bytes to a number of uint8_t or
+  // uint16_t values depending the bit depth.
+  const int step = (rgb_bit_depth > 8) ? rgb_step / 2 : rgb_step;
+  int i = 0;
+  const int w = (pic_width + 1) & ~1;
+  do {
+    const int off = i * step;
+    const int shift = GetPrecisionShift(rgb_bit_depth);
+    if (rgb_bit_depth == 8) {
+      dst[i + 0 * w] = Shift(r_ptr[off], shift);
+      dst[i + 1 * w] = Shift(g_ptr[off], shift);
+      dst[i + 2 * w] = Shift(b_ptr[off], shift);
+    } else {
+      dst[i + 0 * w] = Shift(((uint16_t*)r_ptr)[off], shift);
+      dst[i + 1 * w] = Shift(((uint16_t*)g_ptr)[off], shift);
+      dst[i + 2 * w] = Shift(((uint16_t*)b_ptr)[off], shift);
+    }
+  } while (++i < pic_width);
+  if (pic_width & 1) {  // replicate rightmost pixel
+    dst[pic_width + 0 * w] = dst[pic_width + 0 * w - 1];
+    dst[pic_width + 1 * w] = dst[pic_width + 1 * w - 1];
+    dst[pic_width + 2 * w] = dst[pic_width + 2 * w - 1];
+  }
+}
+
+static void InterpolateTwoRows(const fixed_y_t* const best_y,
+                               const fixed_t* prev_uv,
+                               const fixed_t* cur_uv,
+                               const fixed_t* next_uv,
+                               int w,
+                               fixed_y_t* out1,
+                               fixed_y_t* out2,
+                               int rgb_bit_depth) {
+  const int uv_w = w >> 1;
+  const int len = (w - 1) >> 1;   // length to filter
+  int k = 3;
+  const int bit_depth = rgb_bit_depth + GetPrecisionShift(rgb_bit_depth);
+  while (k-- > 0) {   // process each R/G/B segments in turn
+    // special boundary case for i==0
+    out1[0] = Filter2(cur_uv[0], prev_uv[0], best_y[0], bit_depth);
+    out2[0] = Filter2(cur_uv[0], next_uv[0], best_y[w], bit_depth);
+
+    SharpYuvFilterRow(cur_uv, prev_uv, len, best_y + 0 + 1, out1 + 1,
+                      bit_depth);
+    SharpYuvFilterRow(cur_uv, next_uv, len, best_y + w + 1, out2 + 1,
+                      bit_depth);
+
+    // special boundary case for i == w - 1 when w is even
+    if (!(w & 1)) {
+      out1[w - 1] = Filter2(cur_uv[uv_w - 1], prev_uv[uv_w - 1],
+                            best_y[w - 1 + 0], bit_depth);
+      out2[w - 1] = Filter2(cur_uv[uv_w - 1], next_uv[uv_w - 1],
+                            best_y[w - 1 + w], bit_depth);
+    }
+    out1 += w;
+    out2 += w;
+    prev_uv += uv_w;
+    cur_uv  += uv_w;
+    next_uv += uv_w;
+  }
+}
+
+static WEBP_INLINE int RGBToYUVComponent(int r, int g, int b,
+                                         const int coeffs[4], int sfix) {
+  const int srounder = 1 << (YUV_FIX + sfix - 1);
+  const int luma = coeffs[0] * r + coeffs[1] * g + coeffs[2] * b +
+                   coeffs[3] + srounder;
+  return (luma >> (YUV_FIX + sfix));
+}
+
+static int ConvertWRGBToYUV(const fixed_y_t* best_y, const fixed_t* best_uv,
+                            uint8_t* y_ptr, int y_stride, uint8_t* u_ptr,
+                            int u_stride, uint8_t* v_ptr, int v_stride,
+                            int rgb_bit_depth,
+                            int yuv_bit_depth, int width, int height,
+                            const SharpYuvConversionMatrix* yuv_matrix) {
+  int i, j;
+  const fixed_t* const best_uv_base = best_uv;
+  const int w = (width + 1) & ~1;
+  const int h = (height + 1) & ~1;
+  const int uv_w = w >> 1;
+  const int uv_h = h >> 1;
+  const int sfix = GetPrecisionShift(rgb_bit_depth);
+  const int yuv_max = (1 << yuv_bit_depth) - 1;
+
+  best_uv = best_uv_base;
+  j = 0;
+  do {
+    i = 0;
+    do {
+      const int off = (i >> 1);
+      const int W = best_y[i];
+      const int r = best_uv[off + 0 * uv_w] + W;
+      const int g = best_uv[off + 1 * uv_w] + W;
+      const int b = best_uv[off + 2 * uv_w] + W;
+      const int y = RGBToYUVComponent(r, g, b, yuv_matrix->rgb_to_y, sfix);
+      if (yuv_bit_depth <= 8) {
+        y_ptr[i] = clip_8b(y);
+      } else {
+        ((uint16_t*)y_ptr)[i] = clip(y, yuv_max);
+      }
+    } while (++i < width);
+    best_y += w;
+    best_uv += (j & 1) * 3 * uv_w;
+    y_ptr += y_stride;
+  } while (++j < height);
+
+  best_uv = best_uv_base;
+  j = 0;
+  do {
+    i = 0;
+    do {
+      // Note r, g and b values here are off by W, but a constant offset on all
+      // 3 components doesn't change the value of u and v with a YCbCr matrix.
+      const int r = best_uv[i + 0 * uv_w];
+      const int g = best_uv[i + 1 * uv_w];
+      const int b = best_uv[i + 2 * uv_w];
+      const int u = RGBToYUVComponent(r, g, b, yuv_matrix->rgb_to_u, sfix);
+      const int v = RGBToYUVComponent(r, g, b, yuv_matrix->rgb_to_v, sfix);
+      if (yuv_bit_depth <= 8) {
+        u_ptr[i] = clip_8b(u);
+        v_ptr[i] = clip_8b(v);
+      } else {
+        ((uint16_t*)u_ptr)[i] = clip(u, yuv_max);
+        ((uint16_t*)v_ptr)[i] = clip(v, yuv_max);
+      }
+    } while (++i < uv_w);
+    best_uv += 3 * uv_w;
+    u_ptr += u_stride;
+    v_ptr += v_stride;
+  } while (++j < uv_h);
+  return 1;
+}
+
+//------------------------------------------------------------------------------
+// Main function
+
+static void* SafeMalloc(uint64_t nmemb, size_t size) {
+  const uint64_t total_size = nmemb * (uint64_t)size;
+  if (total_size != (size_t)total_size) return NULL;
+  return malloc((size_t)total_size);
+}
+
+#define SAFE_ALLOC(W, H, T) ((T*)SafeMalloc((uint64_t)(W) * (H), sizeof(T)))
+
+static int DoSharpArgbToYuv(const uint8_t* r_ptr, const uint8_t* g_ptr,
+                            const uint8_t* b_ptr, int rgb_step, int rgb_stride,
+                            int rgb_bit_depth, uint8_t* y_ptr, int y_stride,
+                            uint8_t* u_ptr, int u_stride, uint8_t* v_ptr,
+                            int v_stride, int yuv_bit_depth, int width,
+                            int height,
+                            const SharpYuvConversionMatrix* yuv_matrix,
+                            SharpYuvTransferFunctionType transfer_type) {
+  // we expand the right/bottom border if needed
+  const int w = (width + 1) & ~1;
+  const int h = (height + 1) & ~1;
+  const int uv_w = w >> 1;
+  const int uv_h = h >> 1;
+  const int y_bit_depth = rgb_bit_depth + GetPrecisionShift(rgb_bit_depth);
+  uint64_t prev_diff_y_sum = ~0;
+  int j, iter;
+
+  // TODO(skal): allocate one big memory chunk. But for now, it's easier
+  // for valgrind debugging to have several chunks.
+  fixed_y_t* const tmp_buffer = SAFE_ALLOC(w * 3, 2, fixed_y_t);   // scratch
+  fixed_y_t* const best_y_base = SAFE_ALLOC(w, h, fixed_y_t);
+  fixed_y_t* const target_y_base = SAFE_ALLOC(w, h, fixed_y_t);
+  fixed_y_t* const best_rgb_y = SAFE_ALLOC(w, 2, fixed_y_t);
+  fixed_t* const best_uv_base = SAFE_ALLOC(uv_w * 3, uv_h, fixed_t);
+  fixed_t* const target_uv_base = SAFE_ALLOC(uv_w * 3, uv_h, fixed_t);
+  fixed_t* const best_rgb_uv = SAFE_ALLOC(uv_w * 3, 1, fixed_t);
+  fixed_y_t* best_y = best_y_base;
+  fixed_y_t* target_y = target_y_base;
+  fixed_t* best_uv = best_uv_base;
+  fixed_t* target_uv = target_uv_base;
+  const uint64_t diff_y_threshold = (uint64_t)(3.0 * w * h);
+  int ok;
+  assert(w > 0);
+  assert(h > 0);
+
+  if (best_y_base == NULL || best_uv_base == NULL ||
+      target_y_base == NULL || target_uv_base == NULL ||
+      best_rgb_y == NULL || best_rgb_uv == NULL ||
+      tmp_buffer == NULL) {
+    ok = 0;
+    goto End;
+  }
+
+  // Import RGB samples to W/RGB representation.
+  for (j = 0; j < height; j += 2) {
+    const int is_last_row = (j == height - 1);
+    fixed_y_t* const src1 = tmp_buffer + 0 * w;
+    fixed_y_t* const src2 = tmp_buffer + 3 * w;
+
+    // prepare two rows of input
+    ImportOneRow(r_ptr, g_ptr, b_ptr, rgb_step, rgb_bit_depth, width,
+                 src1);
+    if (!is_last_row) {
+      ImportOneRow(r_ptr + rgb_stride, g_ptr + rgb_stride, b_ptr + rgb_stride,
+                   rgb_step, rgb_bit_depth, width, src2);
+    } else {
+      memcpy(src2, src1, 3 * w * sizeof(*src2));
+    }
+    StoreGray(src1, best_y + 0, w);
+    StoreGray(src2, best_y + w, w);
+
+    UpdateW(src1, target_y, w, rgb_bit_depth, transfer_type);
+    UpdateW(src2, target_y + w, w, rgb_bit_depth, transfer_type);
+    UpdateChroma(src1, src2, target_uv, uv_w, rgb_bit_depth, transfer_type);
+    memcpy(best_uv, target_uv, 3 * uv_w * sizeof(*best_uv));
+    best_y += 2 * w;
+    best_uv += 3 * uv_w;
+    target_y += 2 * w;
+    target_uv += 3 * uv_w;
+    r_ptr += 2 * rgb_stride;
+    g_ptr += 2 * rgb_stride;
+    b_ptr += 2 * rgb_stride;
+  }
+
+  // Iterate and resolve clipping conflicts.
+  for (iter = 0; iter < kNumIterations; ++iter) {
+    const fixed_t* cur_uv = best_uv_base;
+    const fixed_t* prev_uv = best_uv_base;
+    uint64_t diff_y_sum = 0;
+
+    best_y = best_y_base;
+    best_uv = best_uv_base;
+    target_y = target_y_base;
+    target_uv = target_uv_base;
+    j = 0;
+    do {
+      fixed_y_t* const src1 = tmp_buffer + 0 * w;
+      fixed_y_t* const src2 = tmp_buffer + 3 * w;
+      {
+        const fixed_t* const next_uv = cur_uv + ((j < h - 2) ? 3 * uv_w : 0);
+        InterpolateTwoRows(best_y, prev_uv, cur_uv, next_uv, w,
+                           src1, src2, rgb_bit_depth);
+        prev_uv = cur_uv;
+        cur_uv = next_uv;
+      }
+
+      UpdateW(src1, best_rgb_y + 0 * w, w, rgb_bit_depth, transfer_type);
+      UpdateW(src2, best_rgb_y + 1 * w, w, rgb_bit_depth, transfer_type);
+      UpdateChroma(src1, src2, best_rgb_uv, uv_w, rgb_bit_depth, transfer_type);
+
+      // update two rows of Y and one row of RGB
+      diff_y_sum +=
+          SharpYuvUpdateY(target_y, best_rgb_y, best_y, 2 * w, y_bit_depth);
+      SharpYuvUpdateRGB(target_uv, best_rgb_uv, best_uv, 3 * uv_w);
+
+      best_y += 2 * w;
+      best_uv += 3 * uv_w;
+      target_y += 2 * w;
+      target_uv += 3 * uv_w;
+      j += 2;
+    } while (j < h);
+    // test exit condition
+    if (iter > 0) {
+      if (diff_y_sum < diff_y_threshold) break;
+      if (diff_y_sum > prev_diff_y_sum) break;
+    }
+    prev_diff_y_sum = diff_y_sum;
+  }
+
+  // final reconstruction
+  ok = ConvertWRGBToYUV(best_y_base, best_uv_base, y_ptr, y_stride, u_ptr,
+                        u_stride, v_ptr, v_stride, rgb_bit_depth, yuv_bit_depth,
+                        width, height, yuv_matrix);
+
+ End:
+  free(best_y_base);
+  free(best_uv_base);
+  free(target_y_base);
+  free(target_uv_base);
+  free(best_rgb_y);
+  free(best_rgb_uv);
+  free(tmp_buffer);
+  return ok;
+}
+
+#undef SAFE_ALLOC
+
+#if defined(WEBP_USE_THREAD) && !defined(_WIN32)
+#include <pthread.h>  // NOLINT
+
+#define LOCK_ACCESS \
+    static pthread_mutex_t sharpyuv_lock = PTHREAD_MUTEX_INITIALIZER; \
+    if (pthread_mutex_lock(&sharpyuv_lock)) return
+#define UNLOCK_ACCESS_AND_RETURN                  \
+    do {                                          \
+      (void)pthread_mutex_unlock(&sharpyuv_lock); \
+      return;                                     \
+    } while (0)
+#else  // !(defined(WEBP_USE_THREAD) && !defined(_WIN32))
+#define LOCK_ACCESS do {} while (0)
+#define UNLOCK_ACCESS_AND_RETURN return
+#endif  // defined(WEBP_USE_THREAD) && !defined(_WIN32)
+
+// Hidden exported init function.
+// By default SharpYuvConvert calls it with SharpYuvGetCPUInfo. If needed,
+// users can declare it as extern and call it with an alternate VP8CPUInfo
+// function.
+extern VP8CPUInfo SharpYuvGetCPUInfo;
+SHARPYUV_EXTERN void SharpYuvInit(VP8CPUInfo cpu_info_func);
+void SharpYuvInit(VP8CPUInfo cpu_info_func) {
+  static volatile VP8CPUInfo sharpyuv_last_cpuinfo_used =
+      (VP8CPUInfo)&sharpyuv_last_cpuinfo_used;
+  LOCK_ACCESS;
+  // Only update SharpYuvGetCPUInfo when called from external code to avoid a
+  // race on reading the value in SharpYuvConvert().
+  if (cpu_info_func != (VP8CPUInfo)&SharpYuvGetCPUInfo) {
+    SharpYuvGetCPUInfo = cpu_info_func;
+  }
+  if (sharpyuv_last_cpuinfo_used == SharpYuvGetCPUInfo) {
+    UNLOCK_ACCESS_AND_RETURN;
+  }
+
+  SharpYuvInitDsp();
+  SharpYuvInitGammaTables();
+
+  sharpyuv_last_cpuinfo_used = SharpYuvGetCPUInfo;
+  UNLOCK_ACCESS_AND_RETURN;
+}
+
+int SharpYuvConvert(const void* r_ptr, const void* g_ptr, const void* b_ptr,
+                    int rgb_step, int rgb_stride, int rgb_bit_depth,
+                    void* y_ptr, int y_stride, void* u_ptr, int u_stride,
+                    void* v_ptr, int v_stride, int yuv_bit_depth, int width,
+                    int height, const SharpYuvConversionMatrix* yuv_matrix) {
+  SharpYuvOptions options;
+  options.yuv_matrix = yuv_matrix;
+  options.transfer_type = kSharpYuvTransferFunctionSrgb;
+  return SharpYuvConvertWithOptions(
+      r_ptr, g_ptr, b_ptr, rgb_step, rgb_stride, rgb_bit_depth, y_ptr, y_stride,
+      u_ptr, u_stride, v_ptr, v_stride, yuv_bit_depth, width, height, &options);
+}
+
+int SharpYuvOptionsInitInternal(const SharpYuvConversionMatrix* yuv_matrix,
+                                SharpYuvOptions* options, int version) {
+  const int major = (version >> 24);
+  const int minor = (version >> 16) & 0xff;
+  if (options == NULL || yuv_matrix == NULL ||
+      (major == SHARPYUV_VERSION_MAJOR && major == 0 &&
+       minor != SHARPYUV_VERSION_MINOR) ||
+      (major != SHARPYUV_VERSION_MAJOR)) {
+    return 0;
+  }
+  options->yuv_matrix = yuv_matrix;
+  options->transfer_type = kSharpYuvTransferFunctionSrgb;
+  return 1;
+}
+
+int SharpYuvConvertWithOptions(const void* r_ptr, const void* g_ptr,
+                               const void* b_ptr, int rgb_step, int rgb_stride,
+                               int rgb_bit_depth, void* y_ptr, int y_stride,
+                               void* u_ptr, int u_stride, void* v_ptr,
+                               int v_stride, int yuv_bit_depth, int width,
+                               int height, const SharpYuvOptions* options) {
+  const SharpYuvConversionMatrix* yuv_matrix = options->yuv_matrix;
+  SharpYuvTransferFunctionType transfer_type = options->transfer_type;
+  SharpYuvConversionMatrix scaled_matrix;
+  const int rgb_max = (1 << rgb_bit_depth) - 1;
+  const int rgb_round = 1 << (rgb_bit_depth - 1);
+  const int yuv_max = (1 << yuv_bit_depth) - 1;
+  const int sfix = GetPrecisionShift(rgb_bit_depth);
+
+  if (width < 1 || height < 1 || width == INT_MAX || height == INT_MAX ||
+      r_ptr == NULL || g_ptr == NULL || b_ptr == NULL || y_ptr == NULL ||
+      u_ptr == NULL || v_ptr == NULL) {
+    return 0;
+  }
+  if (rgb_bit_depth != 8 && rgb_bit_depth != 10 && rgb_bit_depth != 12 &&
+      rgb_bit_depth != 16) {
+    return 0;
+  }
+  if (yuv_bit_depth != 8 && yuv_bit_depth != 10 && yuv_bit_depth != 12) {
+    return 0;
+  }
+  if (rgb_bit_depth > 8 && (rgb_step % 2 != 0 || rgb_stride % 2 != 0)) {
+    // Step/stride should be even for uint16_t buffers.
+    return 0;
+  }
+  if (yuv_bit_depth > 8 &&
+      (y_stride % 2 != 0 || u_stride % 2 != 0 || v_stride % 2 != 0)) {
+    // Stride should be even for uint16_t buffers.
+    return 0;
+  }
+  // The address of the function pointer is used to avoid a read race.
+  SharpYuvInit((VP8CPUInfo)&SharpYuvGetCPUInfo);
+
+  // Add scaling factor to go from rgb_bit_depth to yuv_bit_depth, to the
+  // rgb->yuv conversion matrix.
+  if (rgb_bit_depth == yuv_bit_depth) {
+    memcpy(&scaled_matrix, yuv_matrix, sizeof(scaled_matrix));
+  } else {
+    int i;
+    for (i = 0; i < 3; ++i) {
+      scaled_matrix.rgb_to_y[i] =
+          (yuv_matrix->rgb_to_y[i] * yuv_max + rgb_round) / rgb_max;
+      scaled_matrix.rgb_to_u[i] =
+          (yuv_matrix->rgb_to_u[i] * yuv_max + rgb_round) / rgb_max;
+      scaled_matrix.rgb_to_v[i] =
+          (yuv_matrix->rgb_to_v[i] * yuv_max + rgb_round) / rgb_max;
+    }
+  }
+  // Also incorporate precision change scaling.
+  scaled_matrix.rgb_to_y[3] = Shift(yuv_matrix->rgb_to_y[3], sfix);
+  scaled_matrix.rgb_to_u[3] = Shift(yuv_matrix->rgb_to_u[3], sfix);
+  scaled_matrix.rgb_to_v[3] = Shift(yuv_matrix->rgb_to_v[3], sfix);
+
+  return DoSharpArgbToYuv(
+      (const uint8_t*)r_ptr, (const uint8_t*)g_ptr, (const uint8_t*)b_ptr,
+      rgb_step, rgb_stride, rgb_bit_depth, (uint8_t*)y_ptr, y_stride,
+      (uint8_t*)u_ptr, u_stride, (uint8_t*)v_ptr, v_stride, yuv_bit_depth,
+      width, height, &scaled_matrix, transfer_type);
+}
+
+//------------------------------------------------------------------------------

sharpyuv/sharpyuv.h

@@ -0,0 +1,181 @@
+// Copyright 2022 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.
+// -----------------------------------------------------------------------------
+//
+// Sharp RGB to YUV conversion.
+
+#ifndef WEBP_SHARPYUV_SHARPYUV_H_
+#define WEBP_SHARPYUV_SHARPYUV_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef SHARPYUV_EXTERN
+#ifdef WEBP_EXTERN
+#define SHARPYUV_EXTERN WEBP_EXTERN
+#else
+// This explicitly marks library functions and allows for changing the
+// signature for e.g., Windows DLL builds.
+#if defined(_WIN32) && defined(WEBP_DLL)
+#define SHARPYUV_EXTERN __declspec(dllexport)
+#elif defined(__GNUC__) && __GNUC__ >= 4
+#define SHARPYUV_EXTERN extern __attribute__((visibility("default")))
+#else
+#define SHARPYUV_EXTERN extern
+#endif /* defined(_WIN32) && defined(WEBP_DLL) */
+#endif /* WEBP_EXTERN */
+#endif /* SHARPYUV_EXTERN */
+
+#ifndef SHARPYUV_INLINE
+#ifdef WEBP_INLINE
+#define SHARPYUV_INLINE WEBP_INLINE
+#else
+#ifndef _MSC_VER
+#if defined(__cplusplus) || !defined(__STRICT_ANSI__) || \
+    (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L)
+#define SHARPYUV_INLINE inline
+#else
+#define SHARPYUV_INLINE
+#endif
+#else
+#define SHARPYUV_INLINE __forceinline
+#endif /* _MSC_VER */
+#endif /* WEBP_INLINE */
+#endif /* SHARPYUV_INLINE */
+
+// SharpYUV API version following the convention from semver.org
+#define SHARPYUV_VERSION_MAJOR 0
+#define SHARPYUV_VERSION_MINOR 4
+#define SHARPYUV_VERSION_PATCH 0
+// Version as a uint32_t. The major number is the high 8 bits.
+// The minor number is the middle 8 bits. The patch number is the low 16 bits.
+#define SHARPYUV_MAKE_VERSION(MAJOR, MINOR, PATCH) \
+  (((MAJOR) << 24) | ((MINOR) << 16) | (PATCH))
+#define SHARPYUV_VERSION                                                \
+  SHARPYUV_MAKE_VERSION(SHARPYUV_VERSION_MAJOR, SHARPYUV_VERSION_MINOR, \
+                        SHARPYUV_VERSION_PATCH)
+
+// Returns the library's version number, packed in hexadecimal. See
+// SHARPYUV_VERSION.
+SHARPYUV_EXTERN int SharpYuvGetVersion(void);
+
+// RGB to YUV conversion matrix, in 16 bit fixed point.
+// y_ = rgb_to_y[0] * r + rgb_to_y[1] * g + rgb_to_y[2] * b + rgb_to_y[3]
+// u_ = rgb_to_u[0] * r + rgb_to_u[1] * g + rgb_to_u[2] * b + rgb_to_u[3]
+// v_ = rgb_to_v[0] * r + rgb_to_v[1] * g + rgb_to_v[2] * b + rgb_to_v[3]
+// Then the values are divided by 1<<16 and rounded.
+// y = (y_ + (1 << 15)) >> 16
+// u = (u_ + (1 << 15)) >> 16
+// v = (v_ + (1 << 15)) >> 16
+//
+// Typically, the offset values rgb_to_y[3], rgb_to_u[3] and rgb_to_v[3] depend
+// on the input's bit depth, e.g., rgb_to_u[3] = 1 << (rgb_bit_depth - 1 + 16).
+// See also sharpyuv_csp.h to get a predefined matrix or generate a matrix.
+typedef struct {
+  int rgb_to_y[4];
+  int rgb_to_u[4];
+  int rgb_to_v[4];
+} SharpYuvConversionMatrix;
+
+typedef struct SharpYuvOptions SharpYuvOptions;
+
+// Enums for transfer functions, as defined in H.273,
+// https://www.itu.int/rec/T-REC-H.273-202107-I/en
+typedef enum SharpYuvTransferFunctionType {
+  // 0 is reserved
+  kSharpYuvTransferFunctionBt709 = 1,
+  // 2 is unspecified
+  // 3 is reserved
+  kSharpYuvTransferFunctionBt470M = 4,
+  kSharpYuvTransferFunctionBt470Bg = 5,
+  kSharpYuvTransferFunctionBt601 = 6,
+  kSharpYuvTransferFunctionSmpte240 = 7,
+  kSharpYuvTransferFunctionLinear = 8,
+  kSharpYuvTransferFunctionLog100 = 9,
+  kSharpYuvTransferFunctionLog100_Sqrt10 = 10,
+  kSharpYuvTransferFunctionIec61966 = 11,
+  kSharpYuvTransferFunctionBt1361 = 12,
+  kSharpYuvTransferFunctionSrgb = 13,
+  kSharpYuvTransferFunctionBt2020_10Bit = 14,
+  kSharpYuvTransferFunctionBt2020_12Bit = 15,
+  kSharpYuvTransferFunctionSmpte2084 = 16,  // PQ
+  kSharpYuvTransferFunctionSmpte428 = 17,
+  kSharpYuvTransferFunctionHlg = 18,
+  kSharpYuvTransferFunctionNum
+} SharpYuvTransferFunctionType;
+
+// Converts RGB to YUV420 using a downsampling algorithm that minimizes
+// artefacts caused by chroma subsampling.
+// This is slower than standard downsampling (averaging of 4 UV values).
+// Assumes that the image will be upsampled using a bilinear filter. If nearest
+// neighbor is used instead, the upsampled image might look worse than with
+// standard downsampling.
+// r_ptr, g_ptr, b_ptr: pointers to the source r, g and b channels. Should point
+//     to uint8_t buffers if rgb_bit_depth is 8, or uint16_t buffers otherwise.
+// rgb_step: distance in bytes between two horizontally adjacent pixels on the
+//     r, g and b channels. If rgb_bit_depth is > 8, it should be a
+//     multiple of 2.
+// rgb_stride: distance in bytes between two vertically adjacent pixels on the
+//     r, g, and b channels. If rgb_bit_depth is > 8, it should be a
+//     multiple of 2.
+// rgb_bit_depth: number of bits for each r/g/b value. One of: 8, 10, 12, 16.
+//     Note: 16 bit input is truncated to 14 bits before conversion to yuv.
+// yuv_bit_depth: number of bits for each y/u/v value. One of: 8, 10, 12.
+// y_ptr, u_ptr, v_ptr: pointers to the destination y, u and v channels.  Should
+//     point to uint8_t buffers if yuv_bit_depth is 8, or uint16_t buffers
+//     otherwise.
+// y_stride, u_stride, v_stride: distance in bytes between two vertically
+//     adjacent pixels on the y, u and v channels. If yuv_bit_depth > 8, they
+//     should be multiples of 2.
+// width, height: width and height of the image in pixels
+// yuv_matrix: RGB to YUV conversion matrix. The matrix values typically
+//     depend on the input's rgb_bit_depth.
+// This function calls SharpYuvConvertWithOptions with a default transfer
+// function of kSharpYuvTransferFunctionSrgb.
+SHARPYUV_EXTERN int SharpYuvConvert(const void* r_ptr, const void* g_ptr,
+                                    const void* b_ptr, int rgb_step,
+                                    int rgb_stride, int rgb_bit_depth,
+                                    void* y_ptr, int y_stride, void* u_ptr,
+                                    int u_stride, void* v_ptr, int v_stride,
+                                    int yuv_bit_depth, int width, int height,
+                                    const SharpYuvConversionMatrix* yuv_matrix);
+
+struct SharpYuvOptions {
+  // This matrix cannot be NULL and can be initialized by
+  // SharpYuvComputeConversionMatrix.
+  const SharpYuvConversionMatrix* yuv_matrix;
+  SharpYuvTransferFunctionType transfer_type;
+};
+
+// Internal, version-checked, entry point
+SHARPYUV_EXTERN int SharpYuvOptionsInitInternal(const SharpYuvConversionMatrix*,
+                                                SharpYuvOptions*, int);
+
+// Should always be called, to initialize a fresh SharpYuvOptions
+// structure before modification. SharpYuvOptionsInit() must have succeeded
+// before using the 'options' object.
+static SHARPYUV_INLINE int SharpYuvOptionsInit(
+    const SharpYuvConversionMatrix* yuv_matrix, SharpYuvOptions* options) {
+  return SharpYuvOptionsInitInternal(yuv_matrix, options, SHARPYUV_VERSION);
+}
+
+SHARPYUV_EXTERN int SharpYuvConvertWithOptions(
+    const void* r_ptr, const void* g_ptr, const void* b_ptr, int rgb_step,
+    int rgb_stride, int rgb_bit_depth, void* y_ptr, int y_stride, void* u_ptr,
+    int u_stride, void* v_ptr, int v_stride, int yuv_bit_depth, int width,
+    int height, const SharpYuvOptions* options);
+
+// TODO(b/194336375): Add YUV444 to YUV420 conversion. Maybe also add 422
+// support (it's rarely used in practice, especially for images).
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif  // WEBP_SHARPYUV_SHARPYUV_H_

sharpyuv/sharpyuv_cpu.c

@@ -1,4 +1,4 @@
-// Copyright 2014 Google Inc. All Rights Reserved.
+// Copyright 2022 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
@@ -7,15 +7,8 @@
 // be found in the AUTHORS file in the root of the source tree.
 // -----------------------------------------------------------------------------
 //
-// AVX2 version of speed-critical encoding functions.
+#include "sharpyuv/sharpyuv_cpu.h"
 
-#include "src/dsp/dsp.h"
+// Include src/dsp/cpu.c to create SharpYuvGetCPUInfo from VP8GetCPUInfo. The
-
+// function pointer is renamed in sharpyuv_cpu.h.
-#if defined(WEBP_USE_AVX2)
+#include "src/dsp/cpu.c"
-
-#endif  // WEBP_USE_AVX2
-
-//------------------------------------------------------------------------------
-// Entry point
-
-WEBP_DSP_INIT_STUB(VP8EncDspInitAVX2)