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
25 #include "libavutil/intreadwrite.h"
26 #include "libavutil/audioconvert.h"
28 #define AT1_SU_SIZE 212
30 static int aea_read_probe(AVProbeData *p)
32 if (p->buf_size <= 2048+212)
35 /* Magic is '00 08 00 00' in Little Endian*/
36 if (AV_RL32(p->buf)==0x800) {
37 int bsm_s, bsm_e, inb_s, inb_e, ch;
40 inb_s = p->buf[2048+1];
41 inb_e = p->buf[2048+210];
42 bsm_e = p->buf[2048+211];
44 if (ch != 1 && ch != 2)
47 /* Check so that the redundant bsm bytes and info bytes are valid
48 * the block size mode bytes have to be the same
49 * the info bytes have to be the same
51 if (bsm_s == bsm_e && inb_s == inb_e)
52 return AVPROBE_SCORE_MAX / 4 + 1;
57 static int aea_read_header(AVFormatContext *s)
59 AVStream *st = avformat_new_stream(s, NULL);
61 return AVERROR(ENOMEM);
63 /* Parse the amount of channels and skip to pos 2048(0x800) */
64 avio_skip(s->pb, 264);
65 st->codec->channels = avio_r8(s->pb);
66 avio_skip(s->pb, 1783);
69 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
70 st->codec->codec_id = CODEC_ID_ATRAC1;
71 st->codec->sample_rate = 44100;
72 st->codec->bit_rate = 292000;
74 if (st->codec->channels != 1 && st->codec->channels != 2) {
75 av_log(s,AV_LOG_ERROR,"Channels %d not supported!\n",st->codec->channels);
79 st->codec->channel_layout = (st->codec->channels == 1) ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
81 st->codec->block_align = AT1_SU_SIZE * st->codec->channels;
85 static int aea_read_packet(AVFormatContext *s, AVPacket *pkt)
87 int ret = av_get_packet(s->pb, pkt, s->streams[0]->codec->block_align);
89 pkt->stream_index = 0;
96 AVInputFormat ff_aea_demuxer = {
98 .long_name = NULL_IF_CONFIG_SMALL("MD STUDIO audio"),
99 .read_probe = aea_read_probe,
100 .read_header = aea_read_header,
101 .read_packet = aea_read_packet,
102 .read_seek = pcm_read_seek,
103 .flags= AVFMT_GENERIC_INDEX,