1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-11-21 10:55:51 +02:00
FFmpeg/libavformat/mgsts.c
Andreas Rheinhardt b800327f4c avformat/avformat: Add FFInputFormat, hide internals of AVInputFormat
This commit does for AVInputFormat what commit
59c9dc82f4 did for AVOutputFormat:
It adds a new type FFInputFormat, moves all the internals
of AVInputFormat to it and adds a now reduced AVInputFormat
as first member.

This does not affect/improve extensibility of both public
or private fields for demuxers (it is still a mess due to lavd).

This is possible since 50f34172e0
(which removed the last usage of an internal field of AVInputFormat
in fftools).

(Hint: tools/probetest.c accesses the internals of FFInputFormat
as well, but given that it is a testing tool this is not considered
a problem.)

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-03-07 08:53:31 -03:00

108 lines
3.0 KiB
C

/*
* Metar Gear Solid: The Twin Snakes demuxer
* Copyright (c) 2012 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
*/
#include "libavutil/intreadwrite.h"
#include "libavutil/intfloat.h"
#include "avformat.h"
#include "demux.h"
#include "riff.h"
static int read_probe(const AVProbeData *p)
{
if (AV_RB32(p->buf ) != 0x000E ||
AV_RB32(p->buf + 4) != 0x0050 ||
AV_RB32(p->buf + 12) != 0x0034)
return 0;
return AVPROBE_SCORE_MAX;
}
static int read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVStream *st;
AVRational fps;
uint32_t chunk_size;
avio_skip(pb, 4);
chunk_size = avio_rb32(pb);
if (chunk_size != 80)
return AVERROR(EIO);
avio_skip(pb, 20);
st = avformat_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
ffstream(st)->need_parsing = AVSTREAM_PARSE_HEADERS;
st->start_time = 0;
st->nb_frames =
st->duration = avio_rb32(pb);
fps = av_d2q(av_int2float(avio_rb32(pb)), INT_MAX);
st->codecpar->width = avio_rb32(pb);
st->codecpar->height = avio_rb32(pb);
avio_skip(pb, 12);
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_tag = avio_rb32(pb);
st->codecpar->codec_id = ff_codec_get_id(ff_codec_bmp_tags,
st->codecpar->codec_tag);
avpriv_set_pts_info(st, 64, fps.den, fps.num);
avio_skip(pb, 20);
return 0;
}
static int read_packet(AVFormatContext *s, AVPacket *pkt)
{
AVIOContext *pb = s->pb;
uint32_t chunk_size, payload_size;
int ret;
if (avio_feof(pb))
return AVERROR_EOF;
avio_skip(pb, 4);
chunk_size = avio_rb32(pb);
avio_skip(pb, 4);
payload_size = avio_rb32(pb);
if (chunk_size < payload_size + 16)
return AVERROR(EIO);
ret = av_get_packet(pb, pkt, payload_size);
if (ret < 0)
return ret;
pkt->pos -= 16;
pkt->duration = 1;
avio_skip(pb, chunk_size - (ret + 16));
return ret;
}
const FFInputFormat ff_mgsts_demuxer = {
.p.name = "mgsts",
.p.long_name = NULL_IF_CONFIG_SMALL("Metal Gear Solid: The Twin Snakes"),
.p.flags = AVFMT_GENERIC_INDEX,
.read_probe = read_probe,
.read_header = read_header,
.read_packet = read_packet,
};