FFmpeg4/libavformat/ingenientdec.c

78 lines
2.4 KiB
C

/*
* RAW Ingenient MJPEG demuxer
* Copyright (c) 2005 Alex Beregszaszi
*
* 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
*/
#include "avformat.h"
#include "rawdec.h"
#include "libavutil/intreadwrite.h"
// http://multimedia.cx/ingenient.txt
static int ingenient_probe(const AVProbeData *p)
{
if ( AV_RN32(p->buf) != AV_RN32("MJPG")
|| p->buf_size < 50
|| AV_RB16(p->buf + 48) != 0xffd8)
return 0;
return AVPROBE_SCORE_MAX * 3 / 4;
}
static int ingenient_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int ret, size, w, h, unk1, unk2;
if (avio_rl32(s->pb) != MKTAG('M', 'J', 'P', 'G'))
return AVERROR(EIO); // FIXME
size = avio_rl32(s->pb);
w = avio_rl16(s->pb);
h = avio_rl16(s->pb);
avio_skip(s->pb, 8); // zero + size (padded?)
avio_skip(s->pb, 2);
unk1 = avio_rl16(s->pb);
unk2 = avio_rl16(s->pb);
avio_skip(s->pb, 22); // ASCII timestamp
av_log(s, AV_LOG_DEBUG, "Ingenient packet: size=%d, width=%d, height=%d, unk1=%d unk2=%d\n",
size, w, h, unk1, unk2);
ret = av_get_packet(s->pb, pkt, size);
if (ret < 0)
return ret;
pkt->stream_index = 0;
return ret;
}
FF_RAWVIDEO_DEMUXER_CLASS(ingenient)
AVInputFormat ff_ingenient_demuxer = {
.name = "ingenient",
.long_name = NULL_IF_CONFIG_SMALL("raw Ingenient MJPEG"),
.priv_data_size = sizeof(FFRawVideoDemuxerContext),
.read_probe = ingenient_probe,
.read_header = ff_raw_video_read_header,
.read_packet = ingenient_read_packet,
.flags = AVFMT_GENERIC_INDEX,
.extensions = "cgi", // FIXME
.raw_codec_id = AV_CODEC_ID_MJPEG,
.priv_class = &ingenient_demuxer_class,
};