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
|
/*
* FILE: codec_l16.c
* AUTHORS: Orion Hodson
*
* Copyright (c) 1998-2001 University College London
* All rights reserved.
*/
#ifndef HIDE_SOURCE_STRINGS
static const char cvsid[] =
"$Id: codec_l16.c,v 1.11 2001/01/08 20:29:56 ucaccsp Exp $";
#endif /* HIDE_SOURCE_STRINGS */
#include "config_unix.h"
#include "config_win32.h"
#include "memory.h"
#include "util.h"
#include "debug.h"
#include "audio_types.h"
#include "codec_types.h"
#include "codec_l16.h"
/* Note payload numbers are dynamic and selected so:
* (a) we always have one codec that can be used at each sample rate and freq
* (b) to backwards match earlier releases.
*/
static codec_format_t cs[] = {
{"Linear-16", "L16-8K-Mono",
"Linear 16 uncompressed audio, please do not use wide area.",
122, 0, 320, {DEV_S16, 8000, 16, 1, 160 * BYTES_PER_SAMPLE}}, /* 20 ms */
{"Linear-16", "L16-8K-Stereo",
"Linear 16 uncompressed audio, please do not use wide area.",
111, 0, 640, {DEV_S16, 8000, 16, 2, 2 * 160 * BYTES_PER_SAMPLE}}, /* 20 ms */
{"Linear-16", "L16-16K-Mono",
"Linear 16 uncompressed audio, please do not use wide area.",
112, 0, 320, {DEV_S16, 16000, 16, 1, 160 * BYTES_PER_SAMPLE}}, /* 10 ms */
{"Linear-16", "L16-16K-Stereo",
"Linear 16 uncompressed audio, please do not use wide area.",
113, 0, 640, {DEV_S16, 16000, 16, 2, 2 * 160 * BYTES_PER_SAMPLE}}, /* 10 ms */
{"Linear-16", "L16-32K-Mono",
"Linear 16 uncompressed audio, please do not use wide area.",
114, 0, 320, {DEV_S16, 32000, 16, 1, 160 * BYTES_PER_SAMPLE}}, /* 5 ms */
{"Linear-16", "L16-32K-Stereo",
"Linear 16 uncompressed audio, please do not use wide area.",
115, 0, 640, {DEV_S16, 32000, 16, 2, 2 * 160 * BYTES_PER_SAMPLE}}, /* 5 ms */
{"Linear-16", "L16-44K-Mono",
"Linear 16 uncompressed audio, please do not use wide area.",
10, 0, 320, {DEV_S16, 44100, 16, 1, 160 * BYTES_PER_SAMPLE}}, /* 3.6 ms */
{"Linear-16", "L16-44K-Stereo",
"Linear 16 uncompressed audio, please do not use wide area.",
11, 0, 640, {DEV_S16, 44100, 16, 2, 2 * 160 * BYTES_PER_SAMPLE}}, /* 3.6 ms */
{"Linear-16", "L16-48K-Mono",
"Linear 16 uncompressed audio, please do not use wide area.",
116, 0, 320, {DEV_S16, 48000, 16, 1, 160 * BYTES_PER_SAMPLE}}, /* 3.3 ms */
{"Linear-16", "L16-48K-Stereo",
"Linear 16 uncompressed audio, please do not use wide area.",
117, 0, 640, {DEV_S16, 48000, 16, 2, 2 * 160 * BYTES_PER_SAMPLE}} /* 3.3 ms */
};
#define L16_NUM_FORMATS sizeof(cs)/sizeof(codec_format_t)
uint16_t
l16_get_formats_count()
{
return (uint16_t)L16_NUM_FORMATS;
}
const codec_format_t *
l16_get_format(uint16_t idx)
{
assert(idx < L16_NUM_FORMATS);
return &cs[idx];
}
int
l16_encode(uint16_t idx, u_char *state, sample *in, coded_unit *out)
{
int samples;
sample *d, *de;
assert(idx < L16_NUM_FORMATS);
UNUSED(state);
out->state = NULL;
out->state_len = 0;
out->data = (u_char*)block_alloc(cs[idx].mean_coded_frame_size);
out->data_len = cs[idx].mean_coded_frame_size;
samples = out->data_len / 2;
d = (sample*)out->data;
de = d + samples;
while (d != de) {
*d = htons(*in);
d++; in++;
}
return samples;
}
int
l16_decode(uint16_t idx, u_char *state, coded_unit *in, sample *out)
{
int samples;
sample *s = NULL, *se = NULL;
assert(idx < L16_NUM_FORMATS);
UNUSED(state);
samples = in->data_len / BYTES_PER_SAMPLE;
s = (sample*)in->data;
se = s + samples;
while(s != se) {
*out = ntohs(*s);
out++; s++;
}
return samples;
}
|
