mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-11-21 10:55:51 +02:00
114 lines
3.1 KiB
C
114 lines
3.1 KiB
C
/*
|
|
* MD STUDIO audio demuxer
|
|
*
|
|
* Copyright (c) 2009 Benjamin Larsson
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file libavformat/aea.c
|
|
*/
|
|
|
|
#include "avformat.h"
|
|
#include "raw.h"
|
|
#include "libavutil/intreadwrite.h"
|
|
|
|
#define AT1_SU_SIZE 212
|
|
|
|
static int aea_read_probe(AVProbeData *p)
|
|
{
|
|
if (p->buf_size <= 2048+212)
|
|
return 0;
|
|
|
|
/* Magic is '00 08 00 00' in Little Endian*/
|
|
if (AV_RL32(p->buf)==0x800) {
|
|
int bsm_s, bsm_e, inb_s, inb_e, ch;
|
|
ch = p->buf[264];
|
|
bsm_s = p->buf[2048];
|
|
inb_s = p->buf[2048+1];
|
|
inb_e = p->buf[2048+210];
|
|
bsm_e = p->buf[2048+211];
|
|
|
|
if (ch != 1 && ch != 2)
|
|
return 0;
|
|
|
|
/* Check so that the redundant bsm bytes and info bytes are valid
|
|
* the block size mode bytes have to be the same
|
|
* the info bytes have to be the same
|
|
* the block size mode and info byte can't be the same
|
|
*/
|
|
if (bsm_s == bsm_e && inb_s == inb_e && bsm_s != inb_s)
|
|
return AVPROBE_SCORE_MAX / 2;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int aea_read_header(AVFormatContext *s,
|
|
AVFormatParameters *ap)
|
|
{
|
|
AVStream *st = av_new_stream(s, 0);
|
|
if (!st)
|
|
return AVERROR(ENOMEM);
|
|
|
|
/* Parse the amount of channels and skip to pos 2048(0x800) */
|
|
url_fskip(s->pb, 264);
|
|
st->codec->channels = get_byte(s->pb);
|
|
url_fskip(s->pb, 1783);
|
|
|
|
|
|
st->codec->codec_type = CODEC_TYPE_AUDIO;
|
|
st->codec->codec_id = CODEC_ID_ATRAC1;
|
|
st->codec->sample_rate = 44100;
|
|
st->codec->bit_rate = 292000;
|
|
|
|
if (st->codec->channels != 1 && st->codec->channels != 2) {
|
|
av_log(s,AV_LOG_ERROR,"Channels %d not supported!\n",st->codec->channels);
|
|
return -1;
|
|
}
|
|
|
|
st->codec->channel_layout = (st->codec->channels == 1) ? CH_LAYOUT_MONO : CH_LAYOUT_STEREO;
|
|
|
|
st->codec->block_align = AT1_SU_SIZE * st->codec->channels;
|
|
return 0;
|
|
}
|
|
|
|
static int aea_read_packet(AVFormatContext *s, AVPacket *pkt)
|
|
{
|
|
int ret = av_get_packet(s->pb, pkt, s->streams[0]->codec->block_align);
|
|
|
|
pkt->stream_index = 0;
|
|
if (ret <= 0)
|
|
return AVERROR(EIO);
|
|
|
|
return ret;
|
|
}
|
|
|
|
AVInputFormat aea_demuxer = {
|
|
"aea",
|
|
NULL_IF_CONFIG_SMALL("MD STUDIO audio"),
|
|
0,
|
|
aea_read_probe,
|
|
aea_read_header,
|
|
aea_read_packet,
|
|
0,
|
|
pcm_read_seek,
|
|
.flags= AVFMT_GENERIC_INDEX,
|
|
.extensions = "aea",
|
|
};
|
|
|