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FFmpeg/libavformat/sdns.c
2023-02-11 11:30:46 +01:00

97 lines
2.8 KiB
C

/*
* SDNS demuxer
* Copyright (c) 2023 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/channel_layout.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "demux.h"
#include "internal.h"
static int sdns_probe(const AVProbeData *p)
{
if (AV_RL32(p->buf) != MKTAG('S','D','N','S'))
return 0;
if (AV_RB32(p->buf + 8) <= 0)
return 0;
if (AV_RB32(p->buf + 12) <= 0 ||
AV_RB32(p->buf + 12) > 128)
return 0;
return AVPROBE_SCORE_MAX / 3;
}
static int sdns_read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVCodecParameters *par;
int channels, ret;
AVStream *st;
avio_skip(pb, 8);
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
par = st->codecpar;
par->codec_type = AVMEDIA_TYPE_AUDIO;
par->codec_id = AV_CODEC_ID_XMA1;
par->sample_rate = avio_rb32(pb);
channels = avio_rb32(pb);
if (channels <= 0 || channels > 128)
return AVERROR_INVALIDDATA;
av_channel_layout_default(&par->ch_layout, channels);
if (par->sample_rate <= 0)
return AVERROR_INVALIDDATA;
par->block_align = 2048;
if ((ret = ff_alloc_extradata(par, 8 + 20 * ((channels + 1) / 2))) < 0)
return ret;
memset(par->extradata, 0, 28);
par->extradata[4] = (channels + 1) / 2;
for (int i = 0; i < par->extradata[4]; i++)
par->extradata[8 + 20 * i + 17] = FFMIN(2, channels - i * 2);
avpriv_set_pts_info(st, 64, 1, par->sample_rate);
avio_seek(pb, 0x1000, SEEK_SET);
return 0;
}
static int sdns_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int ret;
if (avio_feof(s->pb))
return AVERROR_EOF;
ret = av_get_packet(s->pb, pkt, 2048);
pkt->stream_index = 0;
return ret;
}
const AVInputFormat ff_sdns_demuxer = {
.name = "sdns",
.long_name = NULL_IF_CONFIG_SMALL("Xbox SDNS"),
.read_probe = sdns_probe,
.read_header = sdns_read_header,
.read_packet = sdns_read_packet,
.flags = AVFMT_GENERIC_INDEX,
.extensions = "sdns",
};