2 * MD STUDIO audio demuxer
4 * Copyright (c) 2009 Benjamin Larsson
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * @file libavformat/aea.c
29 #include "libavutil/intreadwrite.h"
31 #define AT1_SU_SIZE 212
33 static int aea_read_probe(AVProbeData
*p
)
35 if (p
->buf_size
<= 2048+212)
38 /* Magic is '00 08 00 00' in Little Endian*/
39 if (AV_RL32(p
->buf
)==0x800) {
40 int bsm_s
, bsm_e
, inb_s
, inb_e
, ch
;
43 inb_s
= p
->buf
[2048+1];
44 inb_e
= p
->buf
[2048+210];
45 bsm_e
= p
->buf
[2048+211];
47 if (ch
!= 1 && ch
!= 2)
50 /* Check so that the redundant bsm bytes and info bytes are valid
51 * the block size mode bytes have to be the same
52 * the info bytes have to be the same
53 * the block size mode and info byte can't be the same
55 if (bsm_s
== bsm_e
&& inb_s
== inb_e
&& bsm_s
!= inb_s
)
56 return AVPROBE_SCORE_MAX
/ 2;
61 static int aea_read_header(AVFormatContext
*s
,
62 AVFormatParameters
*ap
)
64 AVStream
*st
= av_new_stream(s
, 0);
66 return AVERROR(ENOMEM
);
68 /* Parse the amount of channels and skip to pos 2048(0x800) */
69 url_fskip(s
->pb
, 264);
70 st
->codec
->channels
= get_byte(s
->pb
);
71 url_fskip(s
->pb
, 1783);
74 st
->codec
->codec_type
= CODEC_TYPE_AUDIO
;
75 st
->codec
->codec_id
= CODEC_ID_ATRAC1
;
76 st
->codec
->sample_rate
= 44100;
77 st
->codec
->bit_rate
= 292000;
79 if (st
->codec
->channels
!= 1 && st
->codec
->channels
!= 2) {
80 av_log(s
,AV_LOG_ERROR
,"Channels %d not supported!\n",st
->codec
->channels
);
84 st
->codec
->channel_layout
= (st
->codec
->channels
== 1) ? CH_LAYOUT_MONO
: CH_LAYOUT_STEREO
;
86 st
->codec
->block_align
= AT1_SU_SIZE
* st
->codec
->channels
;
90 static int aea_read_packet(AVFormatContext
*s
, AVPacket
*pkt
)
92 int ret
= av_get_packet(s
->pb
, pkt
, s
->streams
[0]->codec
->block_align
);
94 pkt
->stream_index
= 0;
101 AVInputFormat aea_demuxer
= {
103 NULL_IF_CONFIG_SMALL("MD STUDIO audio"),
110 .flags
= AVFMT_GENERIC_INDEX
,