// Copyright 2012 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
// -----------------------------------------------------------------------------
//
// simple tool to convert animated GIFs to WebP
//
// Authors: Skal (pascal.massimino@gmail.com)
// Urvang (urvang@google.com)
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_CONFIG_H
#include "webp/config.h"
#endif
#ifdef WEBP_HAVE_GIF
#if defined(HAVE_UNISTD_H) && HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <gif_lib.h>
#include "webp/encode.h"
#include "webp/mux.h"
#include "../examples/example_util.h"
#include "../imageio/imageio_util.h"
#include "./gifdec.h"
#if !defined(STDIN_FILENO)
#define STDIN_FILENO 0
#endif
//------------------------------------------------------------------------------
static int transparent_index = GIF_INDEX_INVALID; // Opaque by default.
static const char* const kErrorMessages[-WEBP_MUX_NOT_ENOUGH_DATA + 1] = {
"WEBP_MUX_NOT_FOUND", "WEBP_MUX_INVALID_ARGUMENT", "WEBP_MUX_BAD_DATA",
"WEBP_MUX_MEMORY_ERROR", "WEBP_MUX_NOT_ENOUGH_DATA"
};
static const char* ErrorString(WebPMuxError err) {
assert(err <= WEBP_MUX_NOT_FOUND && err >= WEBP_MUX_NOT_ENOUGH_DATA);
return kErrorMessages[-err];
}
enum {
METADATA_ICC = (1 << 0),
METADATA_XMP = (1 << 1),
METADATA_ALL = METADATA_ICC | METADATA_XMP
};
//------------------------------------------------------------------------------
static void Help(void) {
printf("Usage:\n");
printf(" gif2webp [options] gif_file -o webp_file\n");
printf("Options:\n");
printf(" -h / -help ............. this help\n");
printf(" -lossy ................. encode image using lossy compression\n");
printf(" -mixed ................. for each frame in the image, pick lossy\n"
" or lossless compression heuristically\n");
printf(" -q <float> ............. quality factor (0:small..100:big)\n");
printf(" -m <int> ............... compression method (0=fast, 6=slowest)\n");
printf(" -min_size .............. minimize output size (default:off)\n"
" lossless compression by default; can be\n"
" combined with -q, -m, -lossy or -mixed\n"
" options\n");
printf(" -kmin <int> ............ min distance between key frames\n");
printf(" -kmax <int> ............ max distance between key frames\n");
printf(" -f <int> ............... filter strength (0=off..100)\n");
printf(" -metadata <string> ..... comma separated list of metadata to\n");
printf(" ");
printf("copy from the input to the output if present\n");
printf(" ");
printf("Valid values: all, none, icc, xmp (default)\n");
printf(" -loop_compatibility .... use compatibility mode for Chrome\n");
printf(" version prior to M62 (inclusive)\n");
printf(" -mt .................... use multi-threading if available\n");
printf("\n");
printf(" -version ............... print version number and exit\n");
printf(" -v ..................... verbose\n");
printf(" -quiet ................. don't print anything\n");
printf("\n");
}
//------------------------------------------------------------------------------
int main(int argc, const char *argv[]) {
int verbose = 0;
int gif_error = GIF_ERROR;
WebPMuxError err = WEBP_MUX_OK;
int ok = 0;
const char *in_file = NULL, *out_file = NULL;
FILE* out = NULL;
GifFileType* gif = NULL;
int frame_duration = 0;
int frame_timestamp = 0;
GIFDisposeMethod orig_dispose = GIF_DISPOSE_NONE;
WebPPicture frame; // Frame rectangle only (not disposed).
WebPPicture curr_canvas; // Not disposed.
WebPPicture prev_canvas; // Disposed.
WebPAnimEncoder* enc = NULL;
WebPAnimEncoderOptions enc_options;
WebPConfig config;
int frame_number = 0; // Whether we are processing the first frame.
int done;
int c;
int quiet = 0;
WebPData webp_data;
int keep_metadata = METADATA_XMP; // ICC not output by default.
WebPData icc_data;
int stored_icc = 0; // Whether we have already stored an ICC profile.
WebPData xmp_data;
int stored_xmp = 0; // Whether we have already stored an XMP profile.
int loop_count = 0; // default: infinite
int stored_loop_count = 0; // Whether we have found an explicit loop count.
int loop_compatibility = 0;
WebPMux* mux = NULL;
int default_kmin = 1; // Whether to use default kmin value.
int default_kmax = 1;
if (!WebPConfigInit(&config) || !WebPAnimEncoderOptionsInit(&enc_options) ||
!WebPPictureInit(&frame) || !WebPPictureInit(&curr_canvas) ||
!WebPPictureInit(&prev_canvas)) {
fprintf(stderr, "Error! Version mismatch!\n");
return -1;
}
config.lossless = 1; // Use lossless compression by default.
WebPDataInit(&webp_data);
WebPDataInit(&icc_data);
WebPDataInit(&xmp_data);
if (argc == 1) {
Help();
return 0;
}
for (c = 1; c < argc; ++c) {
int parse_error = 0;
if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
Help();
return 0;
} else if (!strcmp(argv[c], "-o") && c < argc - 1) {
out_file = argv[++c];
} else if (!strcmp(argv[c], "-lossy")) {
config.lossless = 0;
} else if (!strcmp(argv[c], "-mixed")) {
enc_options.allow_mixed = 1;
config.lossless = 0;
} else if (!strcmp(argv[c], "-loop_compatibility")) {
loop_compatibility = 1;
} else if (!strcmp(argv[c], "-q") && c < argc - 1) {
config.quality = ExUtilGetFloat(argv[++c], &parse_error);
} else if (!strcmp(argv[c], "-m") && c < argc - 1) {
config.method = ExUtilGetInt(argv[++c], 0, &parse_error);
} else if (!strcmp(argv[c], "-min_size")) {
enc_options.minimize_size = 1;
} else if (!strcmp(argv[c], "-kmax") && c < argc - 1) {
enc_options.kmax = ExUtilGetInt(argv[++c], 0, &parse_error);
default_kmax = 0;
} else if (!strcmp(argv[c], "-kmin") && c < argc - 1) {
enc_options.kmin = ExUtilGetInt(argv[++c], 0, &parse_error);
default_kmin = 0;
} else if (!strcmp(argv[c], "-f") && c < argc - 1) {
config.filter_strength = ExUtilGetInt(argv[++c], 0, &parse_error);
} else if (!strcmp(argv[c], "-metadata") && c < argc - 1) {
static const struct {
const char* option;
int flag;
} kTokens[] = {
{ "all", METADATA_ALL },
{ "none", 0 },
{ "icc", METADATA_ICC },
{ "xmp", METADATA_XMP },
};
const size_t kNumTokens = sizeof(kTokens) / sizeof(*kTokens);
const char* start = argv[++c];
const char* const end = start + strlen(start);
keep_metadata = 0;
while (start < end) {
size_t i;
const char* token = strchr(start, ',');
if (token == NULL) token = end;
for (i = 0; i < kNumTokens; ++i) {
if ((size_t)(token - start) == strlen(kTokens[i].option) &&
!strncmp(start, kTokens[i].option, strlen(kTokens[i].option))) {
if (kTokens[i].flag != 0) {
keep_metadata |= kTokens[i].flag;
} else {
keep_metadata = 0;
}
break;
}
}
if (i == kNumTokens) {
fprintf(stderr, "Error! Unknown metadata type '%.*s'\n",
(int)(token - start), start);
Help();
return -1;
}
start = token + 1;
}
} else if (!strcmp(argv[c], "-mt")) {
++config.thread_level;
} else if (!strcmp(argv[c], "-version")) {
const int enc_version = WebPGetEncoderVersion();
const int mux_version = WebPGetMuxVersion();
printf("WebP Encoder version: %d.%d.%d\nWebP Mux version: %d.%d.%d\n",
(enc_version >> 16) & 0xff, (enc_version >> 8) & 0xff,
enc_version & 0xff, (mux_version >> 16) & 0xff,
(mux_version >> 8) & 0xff, mux_version & 0xff);
return 0;
} else if (!strcmp(argv[c], "-quiet")) {
quiet = 1;
enc_options.verbose = 0;
} else if (!strcmp(argv[c], "-v")) {
verbose = 1;
enc_options.verbose = 1;
} else if (!strcmp(argv[c], "--")) {
if (c < argc - 1) in_file = argv[++c];
break;
} else if (argv[c][0] == '-') {
fprintf(stderr, "Error! Unknown option '%s'\n", argv[c]);
Help();
return -1;
} else {
in_file = argv[c];
}
if (parse_error) {
Help();
return -1;
}
}
// Appropriate default kmin, kmax values for lossy and lossless.
if (default_kmin) {
enc_options.kmin = config.lossless ? 9 : 3;
}
if (default_kmax) {
enc_options.kmax = config.lossless ? 17 : 5;
}
if (!WebPValidateConfig(&config)) {
fprintf(stderr, "Error! Invalid configuration.\n");
goto End;
}
if (in_file == NULL) {
fprintf(stderr, "No input file specified!\n");
Help();
goto End;
}
// Start the decoder object
#if LOCAL_GIF_PREREQ(5,0)
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
done = 0;
do {
GifRecordType type;
if (DGifGetRecordType(gif, &type) == GIF_ERROR) goto End;
switch (type) {
case IMAGE_DESC_RECORD_TYPE: {
GIFFrameRect gif_rect;
GifImageDesc* const image_desc = &gif->Image;
if (!DGifGetImageDesc(gif)) goto End;
if (frame_number == 0) {
if (verbose) {
printf("Canvas screen: %d x %d\n", gif->SWidth, gif->SHeight);
}
// Fix some broken GIF global headers that report
// 0 x 0 screen dimension.
if (gif->SWidth == 0 || gif->SHeight == 0) {
image_desc->Left = 0;
image_desc->Top = 0;
gif->SWidth = image_desc->Width;
gif->SHeight = image_desc->Height;
if (gif->SWidth <= 0 || gif->SHeight <= 0) {
goto End;
}
if (verbose) {
printf("Fixed canvas screen dimension to: %d x %d\n",
gif->SWidth, gif->SHeight);
}
}
// Allocate current buffer.
frame.width = gif->SWidth;
frame.height = gif->SHeight;
frame.use_argb = 1;
if (!WebPPictureAlloc(&frame)) goto End;
GIFClearPic(&frame, NULL);
WebPPictureCopy(&frame, &curr_canvas);
WebPPictureCopy(&frame, &prev_canvas);
// Background color.
GIFGetBackgroundColor(gif->SColorMap, gif->SBackGroundColor,
transparent_index,
&enc_options.anim_params.bgcolor);
// Initialize encoder.
enc = WebPAnimEncoderNew(curr_canvas.width, curr_canvas.height,
&enc_options);
if (enc == NULL) {
fprintf(stderr,
"Error! Could not create encoder object. Possibly due to "
"a memory error.\n");
goto End;
}
}
// Some even more broken GIF can have sub-rect with zero width/height.
if (image_desc->Width == 0 || image_desc->Height == 0) {
image_desc->Width = gif->SWidth;
image_desc->Height = gif->SHeight;
}
if (!GIFReadFrame(gif, transparent_index, &gif_rect, &frame)) {
goto End;
}
// Blend frame rectangle with previous canvas to compose full canvas.
// Note that 'curr_canvas' is same as 'prev_canvas' at this point.
GIFBlendFrames(&frame, &gif_rect, &curr_canvas);
if (!WebPAnimEncoderAdd(enc, &curr_canvas, frame_timestamp, &config)) {
fprintf(stderr, "Error while adding frame #%d: %s\n", frame_number,
WebPAnimEncoderGetError(enc));
goto End;
} else {
++frame_number;
}
// Update canvases.
GIFDisposeFrame(orig_dispose, &gif_rect, &prev_canvas, &curr_canvas);
GIFCopyPixels(&curr_canvas, &prev_canvas);
// Force frames with a small or no duration to 100ms to be consistent
// with web browsers and other transcoding tools. This also avoids
// incorrect durations between frames when padding frames are
// discarded.
if (frame_duration <= 10) {
frame_duration = 100;
}
// Update timestamp (for next frame).
frame_timestamp += frame_duration;
// In GIF, graphic control extensions are optional for a frame, so we
// may not get one before reading the next frame. To handle this case,
// we reset frame properties to reasonable defaults for the next frame.
orig_dispose = GIF_DISPOSE_NONE;
frame_duration = 0;
transparent_index = GIF_INDEX_INVALID;
break;
}
case EXTENSION_RECORD_TYPE: {
int extension;
GifByteType *data = NULL;
if (DGifGetExtension(gif, &extension, &data) == GIF_ERROR) {
goto End;
}
if (data == NULL) continue;
switch (extension) {
case COMMENT_EXT_FUNC_CODE: {
break; // Do nothing for now.
}
case GRAPHICS_EXT_FUNC_CODE: {
if (!GIFReadGraphicsExtension(data, &frame_duration, &orig_dispose,
&transparent_index)) {
goto End;
}
break;
}
case PLAINTEXT_EXT_FUNC_CODE: {
break;
}
case APPLICATION_EXT_FUNC_CODE: {
if (data[0] != 11) break; // Chunk is too short
if (!memcmp(data + 1, "NETSCAPE2.0", 11) ||
!memcmp(data + 1, "ANIMEXTS1.0", 11)) {
if (!GIFReadLoopCount(gif, &data, &loop_count)) {
goto End;
}
if (verbose) {
fprintf(stderr, "Loop count: %d\n", loop_count);
}
stored_loop_count = loop_compatibility ? (loop_count != 0) : 1;
} else { // An extension containing metadata.
// We only store the first encountered chunk of each type, and
// only if requested by the user.
const int is_xmp = (keep_metadata & METADATA_XMP) &&
!stored_xmp &&
!memcmp(data + 1, "XMP DataXMP", 11);
const int is_icc = (keep_metadata & METADATA_ICC) &&
!stored_icc &&
!memcmp(data + 1, "ICCRGBG1012", 11);
if (is_xmp || is_icc) {
if (!GIFReadMetadata(gif, &data,
is_xmp ? &xmp_data : &icc_data)) {
goto End;
}
if (is_icc) {
stored_icc = 1;
} else if (is_xmp) {
stored_xmp = 1;
}
}
}
break;
}
default: {
break; // skip
}
}
while (data != NULL) {
if (DGifGetExtensionNext(gif, &data) == GIF_ERROR) goto End;
}
break;
}
case TERMINATE_RECORD_TYPE: {
done = 1;
break;
}
default: {
if (verbose) {
fprintf(stderr, "Skipping over unknown record type %d\n", type);
}
break;
}
}
} while (!done);
// Last NULL frame.
if (!WebPAnimEncoderAdd(enc, NULL, frame_timestamp, NULL)) {
fprintf(stderr, "Error flushing WebP muxer.\n");
fprintf(stderr, "%s\n", WebPAnimEncoderGetError(enc));
}
if (!WebPAnimEncoderAssemble(enc, &webp_data)) {
fprintf(stderr, "%s\n", WebPAnimEncoderGetError(enc));
goto End;
}
if (!loop_compatibility) {
if (!stored_loop_count) {
// if no loop-count element is seen, the default is '1' (loop-once)
// and we need to signal it explicitly in WebP. Note however that
// in case there's a single frame, we still don't need to store it.
if (frame_number > 1) {
stored_loop_count = 1;
loop_count = 1;
}
} else if (loop_count > 0) {
// adapt GIF's semantic to WebP's (except in the infinite-loop case)
loop_count += 1;
}
}
// loop_count of 0 is the default (infinite), so no need to signal it
if (loop_count == 0) stored_loop_count = 0;
if (stored_loop_count || stored_icc || stored_xmp) {
// Re-mux to add loop count and/or metadata as needed.
mux = WebPMuxCreate(&webp_data, 1);
if (mux == NULL) {
fprintf(stderr, "ERROR: Could not re-mux to add loop count/metadata.\n");
goto End;
}
WebPDataClear(&webp_data);
if (stored_loop_count) { // Update loop count.
WebPMuxAnimParams new_params;
err = WebPMuxGetAnimationParams(mux, &new_params);
if (err != WEBP_MUX_OK) {
fprintf(stderr, "ERROR (%s): Could not fetch loop count.\n",
ErrorString(err));
goto End;
}
new_params.loop_count = loop_count;
err = WebPMuxSetAnimationParams(mux, &new_params);
if (err != WEBP_MUX_OK) {
fprintf(stderr, "ERROR (%s): Could not update loop count.\n",
ErrorString(err));
goto End;
}
}
if (stored_icc) { // Add ICCP chunk.
err = WebPMuxSetChunk(mux, "ICCP", &icc_data, 1);
if (verbose) {
fprintf(stderr, "ICC size: %d\n", (int)icc_data.size);
}
if (err != WEBP_MUX_OK) {
fprintf(stderr, "ERROR (%s): Could not set ICC chunk.\n",
ErrorString(err));
goto End;
}
}
if (stored_xmp) { // Add XMP chunk.
err = WebPMuxSetChunk(mux, "XMP ", &xmp_data, 1);
if (verbose) {
fprintf(stderr, "XMP size: %d\n", (int)xmp_data.size);
}
if (err != WEBP_MUX_OK) {
fprintf(stderr, "ERROR (%s): Could not set XMP chunk.\n",
ErrorString(err));
goto End;
}
}
err = WebPMuxAssemble(mux, &webp_data);
if (err != WEBP_MUX_OK) {
fprintf(stderr, "ERROR (%s): Could not assemble when re-muxing to add "
"loop count/metadata.\n", ErrorString(err));
goto End;
}
}
if (out_file != NULL) {
if (!ImgIoUtilWriteFile(out_file, webp_data.bytes, webp_data.size)) {
fprintf(stderr, "Error writing output file: %s\n", out_file);
goto End;
}
if (!quiet) {
if (!strcmp(out_file, "-")) {
fprintf(stderr, "Saved %d bytes to STDIO\n",
(int)webp_data.size);
} else {
fprintf(stderr, "Saved output file (%d bytes): %s\n",
(int)webp_data.size, out_file);
}
}
} else {
if (!quiet) {
fprintf(stderr, "Nothing written; use -o flag to save the result "
"(%d bytes).\n", (int)webp_data.size);
}
}
// All OK.
ok = 1;
gif_error = GIF_OK;
End:
WebPDataClear(&icc_data);
WebPDataClear(&xmp_data);
WebPMuxDelete(mux);
WebPDataClear(&webp_data);
WebPPictureFree(&frame);
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);
}
if (gif != NULL) {
#if LOCAL_GIF_PREREQ(5,1)
DGifCloseFile(gif, &gif_error);
#else
DGifCloseFile(gif);
#endif
}
return !ok;
}
#else // !WEBP_HAVE_GIF
int main(int argc, const char *argv[]) {
fprintf(stderr, "GIF support not enabled in %s.\n", argv[0]);
(void)argc;
return 0;
}
#endif
//------------------------------------------------------------------------------