FFmpeg/libavformat/rawdec.c
2020-12-11 00:23:41 +01:00

219 lines
6.0 KiB
C

/*
* RAW demuxers
* Copyright (c) 2001 Fabrice Bellard
* 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 "internal.h"
#include "avio_internal.h"
#include "rawdec.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "libavutil/pixdesc.h"
#include "libavutil/avassert.h"
#include "libavutil/intreadwrite.h"
#define RAW_PACKET_SIZE 1024
int ff_raw_read_partial_packet(AVFormatContext *s, AVPacket *pkt)
{
FFRawDemuxerContext *raw = s->priv_data;
int ret, size;
size = raw->raw_packet_size;
if ((ret = av_new_packet(pkt, size)) < 0)
return ret;
pkt->pos= avio_tell(s->pb);
pkt->stream_index = 0;
ret = avio_read_partial(s->pb, pkt->data, size);
if (ret < 0) {
av_packet_unref(pkt);
return ret;
}
av_shrink_packet(pkt, ret);
return ret;
}
int ff_raw_audio_read_header(AVFormatContext *s)
{
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = s->iformat->raw_codec_id;
st->need_parsing = AVSTREAM_PARSE_FULL_RAW;
st->start_time = 0;
/* the parameters will be extracted from the compressed bitstream */
return 0;
}
/* MPEG-1/H.263 input */
int ff_raw_video_read_header(AVFormatContext *s)
{
AVStream *st;
FFRawVideoDemuxerContext *s1 = s->priv_data;
int ret = 0;
st = avformat_new_stream(s, NULL);
if (!st) {
ret = AVERROR(ENOMEM);
goto fail;
}
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = s->iformat->raw_codec_id;
st->need_parsing = AVSTREAM_PARSE_FULL_RAW;
st->internal->avctx->framerate = s1->framerate;
avpriv_set_pts_info(st, 64, 1, 1200000);
fail:
return ret;
}
int ff_raw_subtitle_read_header(AVFormatContext *s)
{
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
st->codecpar->codec_id = s->iformat->raw_codec_id;
st->start_time = 0;
return 0;
}
int ff_raw_data_read_header(AVFormatContext *s)
{
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
st->codecpar->codec_id = s->iformat->raw_codec_id;
st->start_time = 0;
return 0;
}
/* Note: Do not forget to add new entries to the Makefile as well. */
#define OFFSET(x) offsetof(FFRawVideoDemuxerContext, x)
#define DEC AV_OPT_FLAG_DECODING_PARAM
const AVOption ff_rawvideo_options[] = {
{ "framerate", "", OFFSET(framerate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC},
{ "raw_packet_size", "", OFFSET(raw_packet_size), AV_OPT_TYPE_INT, {.i64 = RAW_PACKET_SIZE }, 1, INT_MAX, DEC},
{ NULL },
};
#undef OFFSET
#define OFFSET(x) offsetof(FFRawDemuxerContext, x)
const AVOption ff_raw_options[] = {
{ "raw_packet_size", "", OFFSET(raw_packet_size), AV_OPT_TYPE_INT, {.i64 = RAW_PACKET_SIZE }, 1, INT_MAX, DEC},
{ NULL },
};
#if CONFIG_DATA_DEMUXER
FF_RAW_DEMUXER_CLASS(raw_data)
AVInputFormat ff_data_demuxer = {
.name = "data",
.long_name = NULL_IF_CONFIG_SMALL("raw data"),
.read_header = ff_raw_data_read_header,
.read_packet = ff_raw_read_partial_packet,
.raw_codec_id = AV_CODEC_ID_NONE,
.flags = AVFMT_NOTIMESTAMPS,
.priv_data_size = sizeof(FFRawDemuxerContext),\
.priv_class = &raw_data_demuxer_class,\
};
#endif
#if CONFIG_MJPEG_DEMUXER
static int mjpeg_probe(const AVProbeData *p)
{
int i;
int state = -1;
int nb_invalid = 0;
int nb_frames = 0;
for (i = 0; i < p->buf_size - 1; i++) {
int c;
if (p->buf[i] != 0xFF)
continue;
c = p->buf[i+1];
switch (c) {
case 0xD8:
state = 0xD8;
break;
case 0xC0:
case 0xC1:
case 0xC2:
case 0xC3:
case 0xC5:
case 0xC6:
case 0xC7:
case 0xF7:
if (state == 0xD8) {
state = 0xC0;
} else
nb_invalid++;
break;
case 0xDA:
if (state == 0xC0) {
state = 0xDA;
} else
nb_invalid++;
break;
case 0xD9:
if (state == 0xDA) {
state = 0xD9;
nb_frames++;
} else
nb_invalid++;
break;
default:
if ( (c >= 0x02 && c <= 0xBF)
|| c == 0xC8) {
nb_invalid++;
}
}
}
if (nb_invalid*4 + 1 < nb_frames) {
static const char ct_jpeg[] = "\r\nContent-Type: image/jpeg\r\n";
int i;
for (i=0; i<FFMIN(p->buf_size - (int)sizeof(ct_jpeg), 100); i++)
if (!memcmp(p->buf + i, ct_jpeg, sizeof(ct_jpeg) - 1))
return AVPROBE_SCORE_EXTENSION;
if (nb_invalid == 0 && nb_frames > 2)
return AVPROBE_SCORE_EXTENSION / 2;
return AVPROBE_SCORE_EXTENSION / 4;
}
if (!nb_invalid && nb_frames)
return AVPROBE_SCORE_EXTENSION / 4;
return 0;
}
FF_DEF_RAWVIDEO_DEMUXER2(mjpeg, "raw MJPEG video", mjpeg_probe, "mjpg,mjpeg,mpo", AV_CODEC_ID_MJPEG, AVFMT_GENERIC_INDEX|AVFMT_NOTIMESTAMPS)
#endif