1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
/*
* CRYO APC audio format demuxer
* Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com>
*
* 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 <string.h>
#include "avformat.h"
static int apc_probe(AVProbeData *p)
{
if (!strncmp(p->buf, "CRYO_APC", 8))
return AVPROBE_SCORE_MAX;
return 0;
}
static int apc_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
AVIOContext *pb = s->pb;
AVStream *st;
get_le32(pb); /* CRYO */
get_le32(pb); /* _APC */
get_le32(pb); /* 1.20 */
st = av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = CODEC_ID_ADPCM_IMA_WS;
get_le32(pb); /* number of samples */
st->codec->sample_rate = get_le32(pb);
st->codec->extradata_size = 2 * 4;
st->codec->extradata = av_malloc(st->codec->extradata_size +
FF_INPUT_BUFFER_PADDING_SIZE);
if (!st->codec->extradata)
return AVERROR(ENOMEM);
/* initial predictor values for adpcm decoder */
get_buffer(pb, st->codec->extradata, 2 * 4);
st->codec->channels = 1;
if (get_le32(pb))
st->codec->channels = 2;
st->codec->bits_per_coded_sample = 4;
st->codec->bit_rate = st->codec->bits_per_coded_sample * st->codec->channels
* st->codec->sample_rate;
st->codec->block_align = 1;
return 0;
}
#define MAX_READ_SIZE 4096
static int apc_read_packet(AVFormatContext *s, AVPacket *pkt)
{
if (av_get_packet(s->pb, pkt, MAX_READ_SIZE) <= 0)
return AVERROR(EIO);
pkt->stream_index = 0;
return 0;
}
AVInputFormat ff_apc_demuxer = {
"apc",
NULL_IF_CONFIG_SMALL("CRYO APC format"),
0,
apc_probe,
apc_read_header,
apc_read_packet,
};
|
