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FFmpeg/libavformat/gifdec.c

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Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
/*
* GIF demuxer
* Copyright (c) 2012 Vitaliy E Sugrobov
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* GIF demuxer.
*/
#include "avformat.h"
avformat/gifdec: export duration, nb_frames and comment
6 years ago
#include "libavutil/bprint.h"
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
#include "libavutil/intreadwrite.h"
#include "libavutil/opt.h"
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
#include "avio_internal.h"
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
#include "internal.h"
#include "libavcodec/gif.h"
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
#define GIF_PACKET_SIZE 1024
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
typedef struct GIFDemuxContext {
const AVClass *class;
/**
* Time span in hundredths of second before
* the next frame should be drawn on screen.
*/
int delay;
/**
* Minimum allowed delay between frames in hundredths of
* second. Values below this threshold considered to be
* invalid and set to value of default_delay.
*/
int min_delay;
lavf/gif: Add an option max_gif_delay to limit the frame duration. Allows playback for the sample from ticket #4369 in less than 18 hours.
10 years ago
int max_delay;
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
int default_delay;
lavf/gifdec: add loop support. Loop is ignored by default.
12 years ago
/**
* loop options
*/
int total_iter;
int iter_count;
int ignore_loop;
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
} GIFDemuxContext;
/**
* Major web browsers display gifs at ~10-15fps when rate
* is not explicitly set or have too low values. We assume default rate to be 10.
* Default delay = 100hundredths of second / 10fps = 10hos per frame.
*/
#define GIF_DEFAULT_DELAY 10
/**
* By default delay values less than this threshold considered to be invalid.
*/
#define GIF_MIN_DELAY 2
lavf: Constify the probe function argument. Reviewed-by: Lauri Kasanen Reviewed-by: Tomas Härdin
6 years ago
static int gif_probe(const AVProbeData *p)
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
{
/* check magick */
if (memcmp(p->buf, gif87a_sig, 6) && memcmp(p->buf, gif89a_sig, 6))
return 0;
/* width or height contains zero? */
if (!AV_RL16(&p->buf[6]) || !AV_RL16(&p->buf[8]))
return 0;
return AVPROBE_SCORE_MAX;
}
gifdec: resync support This allows decoding gifs that have junk at the begin and also allows byte wise seeking Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
12 years ago
static int resync(AVIOContext *pb)
{
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
ffio_ensure_seekback(pb, 13);
for (int i = 0; i < 6; i++) {
gifdec: resync support This allows decoding gifs that have junk at the begin and also allows byte wise seeking Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
12 years ago
int b = avio_r8(pb);
if (b != gif87a_sig[i] && b != gif89a_sig[i])
i = -(b != 'G');
replace calls to url_feof() with avio_feof() Signed-off-by: James Almer <jamrial@gmail.com> Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
10 years ago
if (avio_feof(pb))
gifdec: resync support This allows decoding gifs that have junk at the begin and also allows byte wise seeking Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
12 years ago
return AVERROR_EOF;
}
return 0;
}
avformat/gifdec: export duration, nb_frames and comment
6 years ago
static int gif_skip_subblocks(AVIOContext *pb)
{
int sb_size, ret = 0;
while (0x00 != (sb_size = avio_r8(pb))) {
if ((ret = avio_skip(pb, sb_size)) < 0)
return ret;
}
return ret;
}
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
static int gif_read_header(AVFormatContext *s)
{
GIFDemuxContext *gdc = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *st;
avformat/gifdec: export duration, nb_frames and comment
6 years ago
int type, width, height, ret, n, flags;
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
int64_t nb_frames = 0, duration = 0, pos;
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
gifdec: resync support This allows decoding gifs that have junk at the begin and also allows byte wise seeking Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
12 years ago
if ((ret = resync(pb)) < 0)
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
return ret;
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
pos = avio_tell(pb);
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
gdc->delay = gdc->default_delay;
gifdec: remove width and height from demuxer context Signed-off-by: Paul B Mahol <onemda@gmail.com>
12 years ago
width = avio_rl16(pb);
height = avio_rl16(pb);
avformat/gifdec: export duration, nb_frames and comment
6 years ago
flags = avio_r8(pb);
avio_skip(pb, 1);
avformat/gifdec: export sample aspect ratio
6 years ago
n = avio_r8(pb);
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
gifdec: remove width and height from demuxer context Signed-off-by: Paul B Mahol <onemda@gmail.com>
12 years ago
if (width == 0 || height == 0)
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
return AVERROR_INVALIDDATA;
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
if (!(pb->seekable & AVIO_SEEKABLE_NORMAL))
goto skip;
avformat/gifdec: export duration, nb_frames and comment
6 years ago
if (flags & 0x80)
avio_skip(pb, 3 * (1 << ((flags & 0x07) + 1)));
while ((type = avio_r8(pb)) != GIF_TRAILER) {
if (avio_feof(pb))
break;
if (type == GIF_EXTENSION_INTRODUCER) {
int subtype = avio_r8(pb);
if (subtype == GIF_COM_EXT_LABEL) {
AVBPrint bp;
int block_size;
avformat/gifdec: -1 -> AV_BPRINT_SIZE_UNLIMITED Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
4 years ago
av_bprint_init(&bp, 0, AV_BPRINT_SIZE_UNLIMITED);
avformat/gifdec: export duration, nb_frames and comment
6 years ago
while ((block_size = avio_r8(pb)) != 0) {
avio_read_to_bprint(pb, &bp, block_size);
}
av_dict_set(&s->metadata, "comment", bp.str, 0);
av_bprint_finalize(&bp, NULL);
} else if (subtype == GIF_GCE_EXT_LABEL) {
int block_size = avio_r8(pb);
if (block_size == 4) {
int delay;
avio_skip(pb, 1);
delay = avio_rl16(pb);
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
delay = delay ? delay : gdc->default_delay;
avformat/gifdec: export duration, nb_frames and comment
6 years ago
duration += delay;
avio_skip(pb, 1);
} else {
avio_skip(pb, block_size);
}
gif_skip_subblocks(pb);
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
} else if (subtype == GIF_APP_EXT_LABEL) {
uint8_t data[256];
int sb_size;
sb_size = avio_r8(pb);
ret = avio_read(pb, data, sb_size);
if (ret < 0 || !sb_size)
break;
if (sb_size == strlen(NETSCAPE_EXT_STR)) {
sb_size = avio_r8(pb);
ret = avio_read(pb, data, sb_size);
if (ret < 0 || !sb_size)
break;
if (sb_size == 3 && data[0] == 1) {
gdc->total_iter = AV_RL16(data+1);
av_log(s, AV_LOG_DEBUG, "Loop count is %d\n", gdc->total_iter);
if (gdc->total_iter == 0)
gdc->total_iter = -1;
}
}
gif_skip_subblocks(pb);
avformat/gifdec: export duration, nb_frames and comment
6 years ago
} else {
gif_skip_subblocks(pb);
}
} else if (type == GIF_IMAGE_SEPARATOR) {
avio_skip(pb, 8);
flags = avio_r8(pb);
if (flags & 0x80)
avio_skip(pb, 3 * (1 << ((flags & 0x07) + 1)));
avio_skip(pb, 1);
gif_skip_subblocks(pb);
nb_frames++;
} else {
break;
}
}
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
skip:
/* jump to start because gif decoder needs header data too */
if (avio_seek(pb, pos - 6, SEEK_SET) != pos - 6)
return AVERROR(EIO);
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
/* GIF format operates with time in "hundredths of second",
* therefore timebase is 1/100 */
avpriv_set_pts_info(st, 64, 1, 100);
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL_RAW;
Merge commit '9200514ad8717c63f82101dc394f4378854325bf' * commit '9200514ad8717c63f82101dc394f4378854325bf': lavf: replace AVStream.codec with AVStream.codecpar This has been a HUGE effort from: - Derek Buitenhuis <derek.buitenhuis@gmail.com> - Hendrik Leppkes <h.leppkes@gmail.com> - wm4 <nfxjfg@googlemail.com> - Clément Bœsch <clement@stupeflix.com> - James Almer <jamrial@gmail.com> - Michael Niedermayer <michael@niedermayer.cc> - Rostislav Pehlivanov <atomnuker@gmail.com> Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
9 years ago
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = AV_CODEC_ID_GIF;
st->codecpar->width = width;
st->codecpar->height = height;
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
if (nb_frames > 1) {
av_reduce(&st->avg_frame_rate.num, &st->avg_frame_rate.den,
100, duration / nb_frames, INT_MAX);
} else if (duration) {
st->avg_frame_rate = (AVRational) { 100, duration };
}
avformat/gifdec: export duration, nb_frames and comment
6 years ago
st->start_time = 0;
st->duration = duration;
st->nb_frames = nb_frames;
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
if (n)
st->codecpar->sample_aspect_ratio = av_make_q(n + 15, 64);
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
return 0;
}
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
static int gif_read_packet(AVFormatContext *s, AVPacket *pkt)
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
{
GIFDemuxContext *gdc = s->priv_data;
AVIOContext *pb = s->pb;
int ret;
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
if ((pb->seekable & AVIO_SEEKABLE_NORMAL) &&
!gdc->ignore_loop && avio_feof(pb) &&
(gdc->total_iter < 0 || (++gdc->iter_count < gdc->total_iter))) {
avio_seek(pb, 0, SEEK_SET);
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
}
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
if ((ret = av_new_packet(pkt, GIF_PACKET_SIZE)) < 0)
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
return ret;
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
pkt->pos = avio_tell(pb);
pkt->stream_index = 0;
ret = avio_read_partial(pb, pkt->data, GIF_PACKET_SIZE);
if (ret < 0) {
av_packet_unref(pkt);
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
return ret;
}
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
av_shrink_packet(pkt, ret);
return ret;
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
}
static const AVOption options[] = {
{ "min_delay" , "minimum valid delay between frames (in hundredths of second)", offsetof(GIFDemuxContext, min_delay) , AV_OPT_TYPE_INT, {.i64 = GIF_MIN_DELAY} , 0, 100 * 60, AV_OPT_FLAG_DECODING_PARAM },
lavf/gif: Add an option max_gif_delay to limit the frame duration. Allows playback for the sample from ticket #4369 in less than 18 hours.
10 years ago
{ "max_gif_delay", "maximum valid delay between frames (in hundredths of seconds)", offsetof(GIFDemuxContext, max_delay) , AV_OPT_TYPE_INT, {.i64 = 65535} , 0, 65535 , AV_OPT_FLAG_DECODING_PARAM },
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
{ "default_delay", "default delay between frames (in hundredths of second)" , offsetof(GIFDemuxContext, default_delay), AV_OPT_TYPE_INT, {.i64 = GIF_DEFAULT_DELAY}, 0, 100 * 60, AV_OPT_FLAG_DECODING_PARAM },
avformat: use AV_OPT_TYPE_BOOL in a bunch of places
9 years ago
{ "ignore_loop" , "ignore loop setting (netscape extension)" , offsetof(GIFDemuxContext, ignore_loop) , AV_OPT_TYPE_BOOL,{.i64 = 1} , 0, 1, AV_OPT_FLAG_DECODING_PARAM },
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
{ NULL },
};
static const AVClass demuxer_class = {
.class_name = "GIF demuxer",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
.category = AV_CLASS_CATEGORY_DEMUXER,
};
avformat: Constify all muxer/demuxers This is possible now that the next-API is gone. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com> Signed-off-by: James Almer <jamrial@gmail.com>
4 years ago
const AVInputFormat ff_gif_demuxer = {
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
.name = "gif",
.long_name = NULL_IF_CONFIG_SMALL("CompuServe Graphics Interchange Format (GIF)"),
.priv_data_size = sizeof(GIFDemuxContext),
.read_probe = gif_probe,
.read_header = gif_read_header,
.read_packet = gif_read_packet,
avformat/gifdec: switch to using gif parser Update fate test, more correct as last packet is not truncated.
2 years ago
.flags = AVFMT_GENERIC_INDEX | AVFMT_NOTIMESTAMPS,
.extensions = "gif",
Gif demuxer Gif demuxer is capable of extracting multiple frames from gif file. In conjunction with gif decoder it implements support for reading animated gifs. Demuxer has two options available to user: default_delay and min_delay. These options are for protection from too rapid gif animations. In practice it is standard approach to slow down rendering of this kind of gifs. If you try to play gif with delay between frames of one hundredth of second (100fps) using one of major web browsers, you get significantly slower playback, around 10 fps. This is because browser detects that delay value is less than some threshold (usually 2 hundredths of second) and reset it to default value (usually 10 hundredths of second, which corresponds to 10fps). Manipulating these options user can achieve the same effect during conversion to some video format. Otherwise user can set them to not protect from rapid animations at all. The other case when these options necessary is for gif images encoded according to gif87a standard since prior to gif89a there was no delay information included in file. Bump lavf minor version. Signed-off-by: Vitaliy E Sugrobov <vsugrob@hotmail.com>
12 years ago
.priv_class = &demuxer_class,
};