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img2webp: convert a sequence of images to an animated webp

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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

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

Change-Id: I23771b90eaf0660f420d7ffd304e704155386286
This commit is contained in:
Pascal Massimino 2016-12-02 11:44:17 +01:00
parent ea72cd60cb
commit 03f40955a3
10 changed files with 493 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
CMakeLists.txt
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@ -6,6 +6,7 @@ project(libwebp C)
option(WEBP_BUILD_CWEBP "Build the cwebp command line tool." OFF)
option(WEBP_BUILD_DWEBP "Build the dwebp command line tool." OFF)
option(WEBP_BUILD_GIF2WEBP "Build the gif2webp conversion tool." OFF)
option(WEBP_BUILD_IMG2WEBP "Build the img2webp animation tool." OFF)
option(WEBP_EXPERIMENTAL_FEATURES "Build with experimental features." OFF)
option(WEBP_ENABLE_SWAP_16BIT_CSP "Enable byte swap for 16 bit colorspaces." OFF)
@ -95,7 +96,8 @@ foreach(I_FILE RANGE ${WEBP_SIMD_FILES_TO_INCLUDE_RANGE})
endforeach()
# Build the executables if asked for.
if(WEBP_BUILD_CWEBP OR WEBP_BUILD_DWEBP OR WEBP_BUILD_GIF2WEBP)
if(WEBP_BUILD_CWEBP OR WEBP_BUILD_DWEBP OR
WEBP_BUILD_GIF2WEBP OR WEBP_BUILD_IMG2WEBP)
# Example utility library.
set(exampleutil_SRCS
${CMAKE_CURRENT_SOURCE_DIR}/examples/stopwatch.h
@ -174,3 +176,14 @@ if(WEBP_BUILD_GIF2WEBP)
${WEBP_DEP_LIBRARIES} ${WEBP_DEP_IMG_LIBRARIES}
)
endif()
if(WEBP_BUILD_IMG2WEBP)
# img2webp
include_directories(${WEBP_DEP_IMG_INCLUDE_DIRS})
set(IMG2WEBP_SRCS ${CMAKE_CURRENT_SOURCE_DIR}/examples/img2webp.c)
parse_Makefile_am(${CMAKE_CURRENT_SOURCE_DIR}/src/mux "IMG2WEBP_SRCS")
add_executable(img2webp ${IMG2WEBP_SRCS})
target_link_libraries(img2webp imagedec webp exampleutil imageioutil
${WEBP_DEP_LIBRARIES} ${WEBP_DEP_IMG_LIBRARIES}
)
endif()

7
Makefile.vc
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@ -331,7 +331,8 @@ ex: $(OUT_LIBS)
all: ex
!ELSE
OUT_EXAMPLES = $(DIRBIN)\cwebp.exe $(DIRBIN)\dwebp.exe
EXTRA_EXAMPLES = $(DIRBIN)\vwebp.exe $(DIRBIN)\webpmux.exe
EXTRA_EXAMPLES = $(DIRBIN)\vwebp.exe $(DIRBIN)\webpmux.exe \
$(DIRBIN)\img2webp.exe
ex: $(OUT_LIBS) $(OUT_EXAMPLES)
all: ex $(EXTRA_EXAMPLES)
@ -355,6 +356,10 @@ $(DIRBIN)\vwebp.exe: $(DIROBJ)\examples\vwebp.obj $(EX_UTIL_OBJS)
$(DIRBIN)\vwebp.exe: $(IMAGEIO_UTIL_OBJS) $(LIBWEBPDEMUX) $(LIBWEBP)
$(DIRBIN)\webpmux.exe: $(DIROBJ)\examples\webpmux.obj $(LIBWEBPMUX)
$(DIRBIN)\webpmux.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS) $(LIBWEBP)
$(DIRBIN)\img2webp.exe: $(DIROBJ)\examples\img2webp.obj $(LIBWEBPMUX)
$(DIRBIN)\img2webp.exe: $(IMAGEIO_DEC_OBJS)
$(DIRBIN)\img2webp.exe: $(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS) $(LIBWEBP)
$(OUT_EXAMPLES): $(EX_UTIL_OBJS) $(LIBWEBP)
$(EX_UTIL_OBJS) $(IMAGEIO_UTIL_OBJS): $(OUTPUT_DIRS)
$(IMAGEIO_DEC_OBJS) $(IMAGEIO_ENC_OBJS): $(OUTPUT_DIRS)

31
README
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@ -413,6 +413,37 @@ $ 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
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

20
build.gradle
View File

@ -368,6 +368,26 @@ model {
}
}
}
img2webp_example(NativeExecutableSpec) {
binaries {
all {
lib library: "example_util", linkage: "static"
lib library: "imagedec", linkage: "static"
lib library: "imageio_util", linkage: "static"
lib library: "webpmux", linkage: "static"
lib library: "webp"
}
}
sources {
c {
source {
srcDir "./examples"
include "img2webp.c"
}
}
}
}
}
tasks {
// Task to test all possible configurations.

6
configure.ac
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@ -556,6 +556,11 @@ AS_IF([test "x$enable_gif" != "xno"], [
AM_CONDITIONAL([BUILD_ANIMDIFF], [test "${build_animdiff}" = "yes"])
AM_CONDITIONAL([BUILD_GIF2WEBP], [test "${build_gif2webp}" = "yes"])
if test "$enable_libwebpmux" = "yes"; then
build_img2webp=yes
fi
AM_CONDITIONAL([BUILD_IMG2WEBP], [test "${build_img2webp}" = "yes"])
dnl === check for WIC support ===
AC_ARG_ENABLE([wic],
@ -710,6 +715,7 @@ dwebp : yes
GIF support : ${gif_support-no}
anim_diff : ${build_animdiff-no}
gif2webp : ${build_gif2webp-no}
img2webp : ${build_img2webp-no}
webpmux : ${enable_libwebpmux-no}
vwebp : ${build_vwebp-no}
])

16
examples/Android.mk
View File

@ -64,3 +64,19 @@ LOCAL_STATIC_LIBRARIES := example_util imageio_util webpmux webp
LOCAL_MODULE := webpmux_example
include $(BUILD_EXECUTABLE)
################################################################################
# img2webp
include $(CLEAR_VARS)
LOCAL_SRC_FILES := \
img2webp.c \
LOCAL_CFLAGS := $(WEBP_CFLAGS)
LOCAL_C_INCLUDES := $(LOCAL_PATH)/../src
LOCAL_STATIC_LIBRARIES := example_util imageio_util imagedec webpmux webp
LOCAL_MODULE := img2webp_example
include $(BUILD_EXECUTABLE)

10
examples/Makefile.am
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@ -7,6 +7,9 @@ endif
if BUILD_GIF2WEBP
bin_PROGRAMS += gif2webp
endif
if BUILD_IMG2WEBP
bin_PROGRAMS += img2webp
endif
if WANT_MUX
bin_PROGRAMS += webpmux
endif
@ -56,6 +59,13 @@ webpmux_CPPFLAGS = $(AM_CPPFLAGS) $(USE_EXPERIMENTAL_CODE)
webpmux_LDADD = libexample_util.la ../imageio/libimageio_util.la
webpmux_LDADD += ../src/mux/libwebpmux.la ../src/libwebp.la
img2webp_SOURCES = img2webp.c
img2webp_CPPFLAGS = $(AM_CPPFLAGS) $(USE_EXPERIMENTAL_CODE)
img2webp_LDADD = libexample_util.la ../imageio/libimageio_util.la
img2webp_LDADD += ../imageio/libimagedec.la
img2webp_LDADD += ../src/mux/libwebpmux.la ../src/libwebp.la
img2webp_LDADD += $(PNG_LIBS) $(JPEG_LIBS) $(TIFF_LIBS)
if BUILD_LIBWEBPDECODER
anim_diff_LDADD += ../src/libwebpdecoder.la
vwebp_LDADD += ../src/libwebpdecoder.la

285
examples/img2webp.c Normal file
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@ -0,0 +1,285 @@
// Copyright 2016 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// generate an animated WebP out of a sequence of images
// (PNG, JPEG, ...)
//
// Example usage:
// img2webp -o out.webp -q 40 -mixed -duration 40 input??.png
//
// Author: skal@google.com (Pascal Massimino)
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_CONFIG_H
#include "webp/config.h"
#endif
#include "../examples/example_util.h"
#include "../imageio/image_dec.h"
#include "../imageio/imageio_util.h"
#include "./stopwatch.h"
#include "webp/encode.h"
#include "webp/mux.h"
//------------------------------------------------------------------------------
static void Help(void) {
printf("Usage:\n\n");
printf(" img2webp [file-level options] [image files...] "
"[per-frame options...]\n");
printf("\n");
printf("File-level options (only used at the start of compression):\n");
printf(" -min_size ............ minimize size\n");
printf(" -loop <int> .......... loop count (default: 0, = infinite loop)\n");
printf(" -kmax <int> .......... maximum number of frame between key-frames\n"
" (0=only keyframes)\n");
printf(" -kmin <int> .......... minimum number of frame between key-frames\n"
" (0=disable key-frames altogether)\n");
printf(" -mixed ............... use mixed lossy/lossless automatic mode\n");
printf(" -v ................... verbose mode\n");
printf(" -h ................... this help\n");
printf("\n");
printf("Per-frame options (only used for subsequent images input):\n");
printf(" -d <int> ............. frame duration in ms (default: 100)\n");
printf(" -lossless ........... use lossless mode (default)\n");
printf(" -lossy ... ........... use lossy mode\n");
printf(" -q <float> ........... quality\n");
printf(" -m <int> ............. method to use\n");
printf("\n");
printf("example: img2webp -loop 2 in0.png -lossy in1.jpg\n"
" -d 80 in2.tiff -o out.webp\n");
}
//------------------------------------------------------------------------------
static int ReadImage(const char filename[], WebPPicture* const pic) {
const uint8_t* data = NULL;
size_t data_size = 0;
WebPImageReader reader;
int ok;
if (!ImgIoUtilReadFile(filename, &data, &data_size)) return 0;
reader = WebPGuessImageReader(data, data_size);
ok = reader(data, data_size, pic, 1, NULL);
free((void*)data);
return ok;
}
static int SetLoopCount(int loop_count, WebPData* const webp_data) {
int ok = 1;
WebPMuxError err;
WebPMuxAnimParams new_params;
WebPMux* const mux = WebPMuxCreate(webp_data, 1);
if (mux == NULL) return 0;
err = WebPMuxGetAnimationParams(mux, &new_params);
ok = (err == WEBP_MUX_OK);
if (ok) {
new_params.loop_count = loop_count;
err = WebPMuxSetAnimationParams(mux, &new_params);
ok = (err == WEBP_MUX_OK);
}
if (ok) {
WebPDataClear(webp_data);
err = WebPMuxAssemble(mux, webp_data);
ok = (err == WEBP_MUX_OK);
}
WebPMuxDelete(mux);
if (!ok) {
fprintf(stderr, "Error during loop-count setting\n");
}
return ok;
}
//------------------------------------------------------------------------------
int main(int argc, char* argv[]) {
const char* output = NULL;
WebPAnimEncoder* enc = NULL;
int verbose = 0;
int pic_num = 0;
int duration = 100;
int timestamp_ms = 0;
int ok = 1;
int loop_count = 0;
int width = 0, height = 0;
WebPAnimEncoderOptions anim_config;
WebPConfig config;
WebPPicture pic;
WebPData webp_data;
int c;
int have_input = 0;
WebPDataInit(&webp_data);
if (!WebPAnimEncoderOptionsInit(&anim_config) ||
!WebPConfigInit(&config) ||
!WebPPictureInit(&pic)) {
fprintf(stderr, "Library version mismatch!\n");
return 1;
}
// 1st pass of option parsing
for (c = 1; ok && c < argc; ++c) {
if (argv[c][0] == '-') {
int parse_error = 0;
if (!strcmp(argv[c], "-o") && c + 1 < argc) {
argv[c] = NULL;
output = argv[++c];
} else if (!strcmp(argv[c], "-kmin") && c + 1 < argc) {
argv[c] = NULL;
anim_config.kmin = ExUtilGetInt(argv[++c], 0, &parse_error);
} else if (!strcmp(argv[c], "-kmax") && c + 1 < argc) {
argv[c] = NULL;
anim_config.kmax = ExUtilGetInt(argv[++c], 0, &parse_error);
} else if (!strcmp(argv[c], "-loop") && c + 1 < argc) {
argv[c] = NULL;
loop_count = ExUtilGetInt(argv[++c], 0, &parse_error);
if (loop_count < 0) {
fprintf(stderr, "Invalid non-positive loop-count (%d)\n", loop_count);
parse_error = 1;
}
} else if (!strcmp(argv[c], "-min_size")) {
anim_config.minimize_size = 1;
} else if (!strcmp(argv[c], "-mixed")) {
anim_config.allow_mixed = 1;
config.lossless = 0;
} else if (!strcmp(argv[c], "-v")) {
verbose = 1;
} else if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
Help();
return 0;
} else {
continue;
}
ok = !parse_error;
if (!ok) goto End;
argv[c] = NULL; // mark option as 'parsed' during 1st pass
} else {
have_input |= 1;
}
}
if (!have_input) {
fprintf(stderr, "No input file(s) for generating animation!\n");
return 0;
}
// image-reading pass
pic_num = 0;
for (c = 1; ok && c < argc; ++c) {
if (argv[c] == NULL) continue;
if (argv[c][0] == '-') { // parse local options
int parse_error = 0;
if (!strcmp(argv[c], "-lossy")) {
if (!anim_config.allow_mixed) config.lossless = 0;
} else if (!strcmp(argv[c], "-lossless")) {
if (!anim_config.allow_mixed) config.lossless = 1;
} else if (!strcmp(argv[c], "-q") && c + 1 < argc) {
config.quality = ExUtilGetFloat(argv[++c], &parse_error);
} else if (!strcmp(argv[c], "-m") && c + 1 < argc) {
config.method = ExUtilGetInt(argv[++c], 0, &parse_error);
} else if (!strcmp(argv[c], "-d") && c + 1 < argc) {
duration = ExUtilGetInt(argv[++c], 0, &parse_error);
if (duration <= 0) {
fprintf(stderr, "Invalid negative duration (%d)\n", duration);
parse_error = 1;
}
} else {
parse_error = 1; // shouldn't be here.
fprintf(stderr, "Unknown option [%s]\n", argv[c]);
}
ok = !parse_error;
if (!ok) goto End;
continue;
}
if (ok) {
ok = WebPValidateConfig(&config);
if (!ok) {
fprintf(stderr, "Invalid configuration.\n");
goto End;
}
}
// read next input image
ok = ReadImage(argv[c], &pic);
if (!ok) goto End;
if (enc == NULL) {
width = pic.width;
height = pic.height;
enc = WebPAnimEncoderNew(width, height, &anim_config);
ok = (enc != NULL);
if (!ok) {
fprintf(stderr, "Could not create WebPAnimEncoder object.\n");
}
}
if (ok) {
ok = (width == pic.width && height == pic.height);
if (!ok) {
fprintf(stderr, "Frame #%d dimension mismatched! "
"Got %d x %d. Was expecting %d x %d.\n",
pic_num, pic.width, pic.height, width, height);
}
}
if (ok) {
ok = WebPAnimEncoderAdd(enc, &pic, timestamp_ms, &config);
if (!ok) {
fprintf(stderr, "Error while adding frame #%d\n", pic_num);
}
}
WebPPictureFree(&pic);
if (!ok) goto End;
if (verbose) {
fprintf(stderr, "Added frame #%3d at time %4d (file: %s)\n",
pic_num, timestamp_ms, argv[c]);
}
timestamp_ms += duration;
++pic_num;
}
// add a last fake frame to signal the last duration
ok = ok && WebPAnimEncoderAdd(enc, NULL, timestamp_ms, NULL);
ok = ok && WebPAnimEncoderAssemble(enc, &webp_data);
if (!ok) {
fprintf(stderr, "Error during final animation assembly.\n");
}
End:
// free resources
WebPAnimEncoderDelete(enc);
if (ok && loop_count > 0) { // Re-mux to add loop count.
ok = SetLoopCount(loop_count, &webp_data);
}
if (ok) {
if (output != NULL) {
ok = ImgIoUtilWriteFile(output, webp_data.bytes, webp_data.size);
if (ok) fprintf(stderr, "output file: %s ", output);
} else {
fprintf(stderr, "[no output file specified] ");
}
}
if (ok) {
fprintf(stderr, "[%d frames, %u bytes].\n",
pic_num, (unsigned int)webp_data.size);
}
WebPDataClear(&webp_data);
return ok ? 0 : 1;
}

10
makefile.unix
View File

@ -326,7 +326,7 @@ OUT_LIBS += src/libwebp.a
EXTRA_LIB = extras/libwebpextras.a
OUT_EXAMPLES = examples/cwebp examples/dwebp
EXTRA_EXAMPLES = examples/gif2webp examples/vwebp examples/webpmux \
examples/anim_diff
examples/anim_diff examples/img2webp
OTHER_EXAMPLES = extras/get_disto extras/webp_quality
OUTPUT = $(OUT_LIBS) $(OUT_EXAMPLES)
@ -374,6 +374,7 @@ examples/dwebp: examples/dwebp.o
examples/gif2webp: examples/gif2webp.o $(GIFDEC_OBJS)
examples/vwebp: examples/vwebp.o
examples/webpmux: examples/webpmux.o
examples/img2webp: examples/img2webp.o
examples/anim_diff: examples/libanim_util.a examples/libgifdec.a
examples/anim_diff: src/demux/libwebpdemux.a examples/libexample_util.a
@ -401,6 +402,10 @@ examples/vwebp: 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/mux/libwebpmux.a src/libwebp.a
examples/img2webp: EXTRA_LIBS += $(CWEBP_LIBS)
extras/get_disto: extras/get_disto.o
extras/get_disto: imageio/libimagedec.a
@ -428,7 +433,8 @@ dist: all
$(INSTALL) -m644 src/demux/libwebpdemux.a $(DESTDIR)/lib
$(INSTALL) -m644 src/mux/libwebpmux.a $(DESTDIR)/lib
umask 022; \
for m in man/[cdv]webp.1 man/gif2webp.1 man/webpmux.1; do \
for m in man/[cdv]webp.1 man/gif2webp.1 man/webpmux.1 \
man/img2webp.1; do \
basenam=$$(basename $$m .1); \
$(GROFF) -t -e -man -T utf8 $$m \
| $(COL) -bx >$(DESTDIR)/doc/$${basenam}.txt; \

97
man/img2webp.1 Normal file
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@ -0,0 +1,97 @@
.\" Hey, EMACS: -*- nroff -*-
.TH IMG2WEBP 1 "December 1, 2016"
.SH NAME
img2webp \- create animated WebP file from a sequence of input images.
.SH SYNOPSIS
.B img2webp
.R [file_level_options] [files] [per_frame_options...]
.br
.SH DESCRIPTION
This manual page documents the
.B img2webp
command.
.PP
\fBimg2webp\fP compresses a sequence of images using the animated WebP format.
Input images can either be PNG, JPEG, TIFF or WebP.
.SH FILE-LEVEL OPTIONS
The file-level options are applied at the beginning of the compression process,
before the input frames are read.
.TP
.BI \-o " string
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
lossless compression by default, but can be combined with \-q, \-m, \-lossy or
\-mixed options.
.TP
.BI \-kmin " int
.TP
.BI \-kmax " int
Specify the minimum and maximum distance between consecutive key frames
(independently decodable frames) in the output animation. The tool will insert
some key frames into the output animation as needed so that this criteria is
satisfied.
.br
.B \-mixed
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 \-loop " int
Specifies the number of times the animation should loop. Using '0' means
'loop indefinitely'.
.TP
.BI \-v
Be more verbose.
.TP
.B \-h, \-help
A short usage summary.
.SH PER-FRAME OPTIONS
The per-frame options are applied for the images following as arguments in the
command line. They can be modified any number of times preceding each particular
input image.
.TP
.BI \-d " int
Specify the image duration in milliseconds.
.TP
.B \-lossless, \-lossy
Compress the next image(s) using lossless or lossy compression mode. The
default mode is lossless.
.TP
.BI \-q " float
Specify the compression factor between 0 and 100. The default is 75.
.TP
.BI \-m " int
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.
.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
The latest source tree is available at
https://chromium.googlesource.com/webm/libwebp
.PP
This manual page was written by Pascal Massimino <pascal.massimino@gmail.com>,
for the Debian project (and may be used by others).
.SH SEE ALSO
.BR webpmux (1),
.BR gif2webp (1)
.br
Please refer to http://developers.google.com/speed/webp/ for additional
information.