2 * CRYO APC audio format demuxer
3 * Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com>
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 #include "libavutil/channel_layout.h"
28 static int apc_probe(AVProbeData
*p
)
30 if (!strncmp(p
->buf
, "CRYO_APC", 8))
31 return AVPROBE_SCORE_MAX
;
36 static int apc_read_header(AVFormatContext
*s
)
38 AVIOContext
*pb
= s
->pb
;
41 avio_rl32(pb
); /* CRYO */
42 avio_rl32(pb
); /* _APC */
43 avio_rl32(pb
); /* 1.20 */
45 st
= avformat_new_stream(s
, NULL
);
47 return AVERROR(ENOMEM
);
49 st
->codec
->codec_type
= AVMEDIA_TYPE_AUDIO
;
50 st
->codec
->codec_id
= AV_CODEC_ID_ADPCM_IMA_APC
;
52 avio_rl32(pb
); /* number of samples */
53 st
->codec
->sample_rate
= avio_rl32(pb
);
55 /* initial predictor values for adpcm decoder */
56 if (ff_get_extradata(st
->codec
, pb
, 2 * 4) < 0)
57 return AVERROR(ENOMEM
);
60 st
->codec
->channels
= 2;
61 st
->codec
->channel_layout
= AV_CH_LAYOUT_STEREO
;
63 st
->codec
->channels
= 1;
64 st
->codec
->channel_layout
= AV_CH_LAYOUT_MONO
;
67 st
->codec
->bits_per_coded_sample
= 4;
68 st
->codec
->bit_rate
= st
->codec
->bits_per_coded_sample
* st
->codec
->channels
69 * st
->codec
->sample_rate
;
70 st
->codec
->block_align
= 1;
75 #define MAX_READ_SIZE 4096
77 static int apc_read_packet(AVFormatContext
*s
, AVPacket
*pkt
)
79 if (av_get_packet(s
->pb
, pkt
, MAX_READ_SIZE
) <= 0)
81 pkt
->flags
&= ~AV_PKT_FLAG_CORRUPT
;
82 pkt
->stream_index
= 0;
86 AVInputFormat ff_apc_demuxer
= {
88 .long_name
= NULL_IF_CONFIG_SMALL("CRYO APC"),
89 .read_probe
= apc_probe
,
90 .read_header
= apc_read_header
,
91 .read_packet
= apc_read_packet
,