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
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
/*
* Creative Voice File demuxer.
* Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org>
*
* 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 "voc.h"
static int voc_probe(AVProbeData *p)
{
int version, check;
if (memcmp(p->buf, voc_magic, sizeof(voc_magic) - 1))
return 0;
version = AV_RL16(p->buf + 22);
check = AV_RL16(p->buf + 24);
if (~version + 0x1234 != check)
return 10;
return AVPROBE_SCORE_MAX;
}
static int voc_read_header(AVFormatContext *s, AVFormatParameters *ap)
{
voc_dec_context_t *voc = s->priv_data;
ByteIOContext *pb = &s->pb;
int header_size;
AVStream *st;
url_fskip(pb, 20);
header_size = get_le16(pb) - 22;
if (header_size != 4) {
av_log(s, AV_LOG_ERROR, "unknown header size: %d\n", header_size);
return AVERROR_NOTSUPP;
}
url_fskip(pb, header_size);
st = av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = CODEC_TYPE_AUDIO;
voc->remaining_size = 0;
return 0;
}
int
voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size)
{
voc_dec_context_t *voc = s->priv_data;
AVCodecContext *dec = st->codec;
ByteIOContext *pb = &s->pb;
voc_type_t type;
int size;
int sample_rate = 0;
int channels = 1;
while (!voc->remaining_size) {
type = get_byte(pb);
if (type == VOC_TYPE_EOF)
return AVERROR_IO;
voc->remaining_size = get_le24(pb);
max_size -= 4;
switch (type) {
case VOC_TYPE_VOICE_DATA:
dec->sample_rate = 1000000 / (256 - get_byte(pb));
if (sample_rate)
dec->sample_rate = sample_rate;
dec->channels = channels;
dec->codec_id = codec_get_id(voc_codec_tags, get_byte(pb));
dec->bits_per_sample = av_get_bits_per_sample(dec->codec_id);
voc->remaining_size -= 2;
max_size -= 2;
channels = 1;
break;
case VOC_TYPE_VOICE_DATA_CONT:
break;
case VOC_TYPE_EXTENDED:
sample_rate = get_le16(pb);
get_byte(pb);
channels = get_byte(pb) + 1;
sample_rate = 256000000 / (channels * (65536 - sample_rate));
voc->remaining_size = 0;
max_size -= 4;
break;
case VOC_TYPE_NEW_VOICE_DATA:
dec->sample_rate = get_le32(pb);
dec->bits_per_sample = get_byte(pb);
dec->channels = get_byte(pb);
dec->codec_id = codec_get_id(voc_codec_tags, get_le16(pb));
url_fskip(pb, 4);
voc->remaining_size -= 12;
max_size -= 12;
break;
default:
url_fskip(pb, voc->remaining_size);
max_size -= voc->remaining_size;
voc->remaining_size = 0;
break;
}
}
dec->bit_rate = dec->sample_rate * dec->bits_per_sample;
if (max_size <= 0)
max_size = 2048;
size = FFMIN(voc->remaining_size, max_size);
voc->remaining_size -= size;
return av_get_packet(pb, pkt, size);
}
static int voc_read_packet(AVFormatContext *s, AVPacket *pkt)
{
return voc_get_packet(s, pkt, s->streams[0], 0);
}
AVInputFormat voc_demuxer = {
"voc",
"Creative Voice File format",
sizeof(voc_dec_context_t),
voc_probe,
voc_read_header,
voc_read_packet,
.codec_tag=(const AVCodecTag*[]){voc_codec_tags, 0},
};
|
