ffmpeg/libavformat/boadec.c

90 lines
2.8 KiB
C

/*
* Black ops audio demuxer
* Copyright (c) 2013 Michael Niedermayer
*
* 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 "libavcodec/internal.h"
#include "avformat.h"
#include "demux.h"
#include "internal.h"
static int probe(const AVProbeData *p)
{
if (p->buf_size < 2096)
return 0;
if ( AV_RL32(p->buf ) != 1
|| AV_RL32(p->buf + 8) > 100000
|| AV_RL32(p->buf + 12) > 8
|| AV_RL32(p->buf + 16) != 2096
||!AV_RL32(p->buf + 21)
|| AV_RL16(p->buf + 25) != 2096
|| AV_RL32(p->buf + 48) % AV_RL32(p->buf + 21)
)
return 0;
return AVPROBE_SCORE_EXTENSION;
}
static int read_header(AVFormatContext *s)
{
AVStream *st = avformat_new_stream(s, NULL);
uint32_t data_offset;
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = AV_CODEC_ID_ADPCM_MS;
avio_rl32(s->pb);
avio_rl32(s->pb);
st->codecpar->sample_rate = avio_rl32(s->pb);
st->codecpar->ch_layout.nb_channels = avio_rl32(s->pb);
if (st->codecpar->ch_layout.nb_channels > FF_SANE_NB_CHANNELS ||
st->codecpar->ch_layout.nb_channels <= 0)
return AVERROR(ENOSYS);
ffformatcontext(s)->data_offset = data_offset = avio_rl32(s->pb);
avio_r8(s->pb);
st->codecpar->block_align = avio_rl32(s->pb);
if (st->codecpar->block_align > INT_MAX / FF_SANE_NB_CHANNELS || st->codecpar->block_align <= 0)
return AVERROR_INVALIDDATA;
st->codecpar->block_align *= st->codecpar->ch_layout.nb_channels;
avio_seek(s->pb, data_offset, SEEK_SET);
return 0;
}
static int read_packet(AVFormatContext *s, AVPacket *pkt)
{
AVStream *st = s->streams[0];
return av_get_packet(s->pb, pkt, st->codecpar->block_align);
}
const FFInputFormat ff_boa_demuxer = {
.p.name = "boa",
.p.long_name = NULL_IF_CONFIG_SMALL("Black Ops Audio"),
.p.flags = AVFMT_GENERIC_INDEX,
.read_probe = probe,
.read_header = read_header,
.read_packet = read_packet,
};