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/*
* SMJPEG demuxer
* Copyright (c) 2011 Paul B Mahol
*
* 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
* This is a demuxer for Loki SDL Motion JPEG files
*/
#include "avformat.h"
#include "internal.h"
#include "riff.h"
#include "smjpeg.h"
typedef struct SMJPEGContext {
int audio_stream_index;
int video_stream_index;
} SMJPEGContext;
static int smjpeg_probe(AVProbeData *p)
{
if (!memcmp(p->buf, SMJPEG_MAGIC, 8))
return AVPROBE_SCORE_MAX;
return 0;
}
static int smjpeg_read_header(AVFormatContext *s)
{
SMJPEGContext *sc = s->priv_data;
AVStream *ast = NULL, *vst = NULL;
AVIOContext *pb = s->pb;
uint32_t version, htype, hlength, duration;
char *comment;
avio_skip(pb, 8); // magic
version = avio_rb32(pb);
if (version)
avpriv_request_sample(s, "Unknown version %d", version);
duration = avio_rb32(pb); // in msec
while (!url_feof(pb)) {
htype = avio_rl32(pb);
switch (htype) {
case SMJPEG_TXT:
hlength = avio_rb32(pb);
if (!hlength || hlength > 512)
return AVERROR_INVALIDDATA;
comment = av_malloc(hlength + 1);
if (!comment)
return AVERROR(ENOMEM);
if (avio_read(pb, comment, hlength) != hlength) {
av_freep(&comment);
av_log(s, AV_LOG_ERROR, "error when reading comment\n");
return AVERROR_INVALIDDATA;
}
comment[hlength] = 0;
av_dict_set(&s->metadata, "comment", comment,
AV_DICT_DONT_STRDUP_VAL);
break;
case SMJPEG_SND:
if (ast) {
avpriv_request_sample(s, "Multiple audio streams");
return AVERROR_PATCHWELCOME;
}
hlength = avio_rb32(pb);
if (hlength < 8)
return AVERROR_INVALIDDATA;
ast = avformat_new_stream(s, 0);
if (!ast)
return AVERROR(ENOMEM);
ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
ast->codec->sample_rate = avio_rb16(pb);
ast->codec->bits_per_coded_sample = avio_r8(pb);
ast->codec->channels = avio_r8(pb);
ast->codec->codec_tag = avio_rl32(pb);
ast->codec->codec_id = ff_codec_get_id(ff_codec_smjpeg_audio_tags,
ast->codec->codec_tag);
ast->duration = duration;
sc->audio_stream_index = ast->index;
avpriv_set_pts_info(ast, 32, 1, 1000);
avio_skip(pb, hlength - 8);
break;
case SMJPEG_VID:
if (vst) {
avpriv_request_sample(s, "Multiple video streams");
return AVERROR_INVALIDDATA;
}
hlength = avio_rb32(pb);
if (hlength < 12)
return AVERROR_INVALIDDATA;
vst = avformat_new_stream(s, 0);
if (!vst)
return AVERROR(ENOMEM);
vst->nb_frames = avio_rb32(pb);
vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
vst->codec->width = avio_rb16(pb);
vst->codec->height = avio_rb16(pb);
vst->codec->codec_tag = avio_rl32(pb);
vst->codec->codec_id = ff_codec_get_id(ff_codec_smjpeg_video_tags,
vst->codec->codec_tag);
vst->duration = duration;
sc->video_stream_index = vst->index;
avpriv_set_pts_info(vst, 32, 1, 1000);
avio_skip(pb, hlength - 12);
break;
case SMJPEG_HEND:
return 0;
default:
av_log(s, AV_LOG_ERROR, "unknown header %x\n", htype);
return AVERROR_INVALIDDATA;
}
}
return AVERROR_EOF;
}
static int smjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
{
SMJPEGContext *sc = s->priv_data;
uint32_t dtype, size, timestamp;
int64_t pos;
int ret;
if (url_feof(s->pb))
return AVERROR_EOF;
pos = avio_tell(s->pb);
dtype = avio_rl32(s->pb);
switch (dtype) {
case SMJPEG_SNDD:
timestamp = avio_rb32(s->pb);
size = avio_rb32(s->pb);
ret = av_get_packet(s->pb, pkt, size);
pkt->stream_index = sc->audio_stream_index;
pkt->pts = timestamp;
pkt->pos = pos;
break;
case SMJPEG_VIDD:
timestamp = avio_rb32(s->pb);
size = avio_rb32(s->pb);
ret = av_get_packet(s->pb, pkt, size);
pkt->stream_index = sc->video_stream_index;
pkt->pts = timestamp;
pkt->pos = pos;
break;
case SMJPEG_DONE:
ret = AVERROR_EOF;
break;
default:
av_log(s, AV_LOG_ERROR, "unknown chunk %x\n", dtype);
ret = AVERROR_INVALIDDATA;
break;
}
return ret;
}
AVInputFormat ff_smjpeg_demuxer = {
.name = "smjpeg",
.long_name = NULL_IF_CONFIG_SMALL("Loki SDL MJPEG"),
.priv_data_size = sizeof(SMJPEGContext),
.read_probe = smjpeg_probe,
.read_header = smjpeg_read_header,
.read_packet = smjpeg_read_packet,
.extensions = "mjpg",
.flags = AVFMT_GENERIC_INDEX,
};
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