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
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
|
/*
* amr file format
* Copyright (c) 2001 ffmpeg project
*
* This library 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 of the License, or (at your option) any later version.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
Write and read amr data according to RFC3267, http://www.ietf.org/rfc/rfc3267.txt?number=3267
Only amr narrowband (not amr-wb) is supported for now.
*/
#include "avformat.h"
#include "avi.h"
static const unsigned char AMR_header [] = "#!AMR\n";
/* AMR_FILE header */
static int put_amr_header(ByteIOContext *pb, AVCodecContext *enc)
{
put_tag(pb, AMR_header); /* magic number */
return 0;
}
static int amr_write_header(AVFormatContext *s)
{
ByteIOContext *pb = &s->pb;
s->priv_data = NULL;
/* format header */
if (put_amr_header(pb, &s->streams[0]->codec) < 0) {
return -1;
}
put_flush_packet(pb);
return 0;
}
static int amr_write_packet(AVFormatContext *s, int stream_index_ptr,
uint8_t *buf, int size, int force_pts)
{
put_buffer(&s->pb, buf, size);
put_flush_packet(&s->pb);
return 0;
}
static int amr_write_trailer(AVFormatContext *s)
{
return 0;
}
static int amr_probe(AVProbeData *p)
{
/* check file header */
if (p->buf_size < 6)
return 0;
if(memcmp(p->buf,AMR_header,6)==0)
return AVPROBE_SCORE_MAX;
else
return 0;
}
/* amr input */
static int amr_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
ByteIOContext *pb = &s->pb;
AVStream *st;
u_int8_t header[6];
get_buffer(pb, header, 6);
if(memcmp(header,AMR_header,6)!=0)
{
return -1;
}
st = av_new_stream(s, 0);
if (!st)
return AVERROR_NOMEM;
st->codec.codec_type = CODEC_TYPE_AUDIO;
st->codec.codec_tag = CODEC_ID_AMR_NB;
st->codec.codec_id = CODEC_ID_AMR_NB;
st->codec.channels = 1;
st->codec.sample_rate = 8000;
return 0;
}
#define MAX_SIZE 32
static int amr_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
static u_int16_t packed_size[16] = {12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0};
u_int8_t toc, q, ft;
int read;
int size;
if (url_feof(&s->pb))
return -EIO;
toc=0;
toc=get_byte(&s->pb);
q = (toc >> 2) & 0x01;
ft = (toc >> 3) & 0x0F;
size=packed_size[ft];
//printf("amr_read_packet size=%d\n",size);
if (av_new_packet(pkt, size+1))
return -EIO;
pkt->stream_index = 0;
pkt->data[0]=toc;
read = get_buffer(&s->pb, pkt->data+1, size);
if (read != size)
{
av_free_packet(pkt);
return -EIO;
}
return 0;
}
static int amr_read_close(AVFormatContext *s)
{
return 0;
}
static AVInputFormat amr_iformat = {
"amr",
"3gpp amr file format",
0,
amr_probe,
amr_read_header,
amr_read_packet,
amr_read_close,
};
static AVOutputFormat amr_oformat = {
"amr",
"3gpp amr file format",
"audio/amr",
"amr",
0,
CODEC_ID_AMR_NB,
CODEC_ID_NONE,
amr_write_header,
amr_write_packet,
amr_write_trailer,
};
int amr_init(void)
{
av_register_input_format(&amr_iformat);
av_register_output_format(&amr_oformat);
return 0;
}
|
