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
|
/*
* FILE: codec_gsm.h
* AUTHORS: Orion Hodson
*
* Copyright (c) 1998-2001 University College London
* All rights reserved.
*/
#ifndef HIDE_SOURCE_STRINGS
static const char cvsid[] =
"$Id: codec_gsm.c,v 1.15 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_gsm.h"
#include "cx_gsm.h"
static codec_format_t cs[] = {
{"GSM", "GSM-8K-Mono",
"Full rate GSM speech codec. (c) 1992 J. Degener and C. Bormann, Technische Universitaet Berlin.",
3, 0, GSM_FRAMESIZE,
{DEV_S16, 8000, 16, 1, 160 * BYTES_PER_SAMPLE}},
{"GSM", "GSM-16K-Mono",
"Full rate GSM speech codec. (c) 1992 J. Degener and C. Bormann, Technische Universitaet Berlin.",
118, 0, GSM_FRAMESIZE,
{DEV_S16, 16000, 16, 1, 160 * BYTES_PER_SAMPLE}},
{"GSM", "GSM-32K-Mono",
"Full rate GSM speech codec. (c) 1992 J. Degener and C. Bormann, Technische Universitaet Berlin.",
119, 0, GSM_FRAMESIZE,
{DEV_S16, 32000, 16, 1, 160 * BYTES_PER_SAMPLE}},
{"GSM", "GSM-48K-Mono",
"Full rate GSM speech codec. (c) 1992 J. Degener and C. Bormann, Technische Universitaet Berlin.",
123, 0, GSM_FRAMESIZE,
{DEV_S16, 48000, 16, 1, 160 * BYTES_PER_SAMPLE}}
};
#define GSM_NUM_FORMATS (sizeof(cs)/sizeof(codec_format_t))
uint16_t
gsm_get_formats_count()
{
return GSM_NUM_FORMATS;
}
const codec_format_t*
gsm_get_format(uint16_t idx)
{
assert(idx < GSM_NUM_FORMATS);
return &cs[idx];
}
int
gsm_state_create(uint16_t idx, u_char **state)
{
assert(idx < GSM_NUM_FORMATS);
UNUSED(idx);
*state = (u_char*) gsm_create();
return GSM_FRAMESIZE;
}
void
gsm_state_destroy(uint16_t idx, u_char **state)
{
assert(idx < GSM_NUM_FORMATS);
UNUSED(idx);
gsm_destroy((gsm)*state);
*state = (u_char*)NULL;
}
int
gsm_encoder (uint16_t idx, u_char *state, sample *in, coded_unit *out)
{
assert(idx < GSM_NUM_FORMATS);
assert(state);
assert(in);
assert(out);
UNUSED(idx);
out->state = NULL;
out->state_len = 0;
out->data = (u_char*)block_alloc(GSM_FRAMESIZE);
out->data_len = GSM_FRAMESIZE;
gsm_encode((gsm)state, in, (gsm_byte*)out->data);
return out->data_len;
}
int
gsm_decoder (uint16_t idx, u_char *state, coded_unit *in, sample *out)
{
assert(idx < GSM_NUM_FORMATS);
assert(state);
assert(in && in->data);
assert(out);
UNUSED(idx);
gsm_decode((gsm)state, (gsm_byte*)in->data, (gsm_signal*)out);
return cs[idx].format.bytes_per_block / BYTES_PER_SAMPLE;
}
int
gsm_repair (uint16_t idx, u_char *state, uint16_t consec_lost,
coded_unit *prev, coded_unit *missing, coded_unit *next)
{
/* GSM 06.11 repair mechanism */
int i;
gsm_byte *rep = NULL;
char xmaxc;
assert(prev);
assert(missing);
if (missing->data) {
debug_msg("lpc_repair: missing unit had data!\n");
block_free(missing->data, missing->data_len);
}
missing->data = (u_char*)block_alloc(GSM_FRAMESIZE);
missing->data_len = GSM_FRAMESIZE;
rep = (gsm_byte*)missing->data;
memcpy(rep, prev->data, GSM_FRAMESIZE);
if (consec_lost > 0) {
/* If not first loss start fading */
for(i=6;i<28;i+=7) {
xmaxc = (rep[i] & 0x1f) << 1;
xmaxc |= (rep[i+1] >> 7) & 0x01;
if (xmaxc > 4) {
xmaxc -= 4;
} else {
xmaxc = 0;
}
rep[i] = (rep[i] & 0xe0) | (xmaxc >> 1);
rep[i+1] = (rep[i+1] & 0x7f) | ((xmaxc & 0x01) << 7);
}
}
UNUSED(idx);
UNUSED(state);
UNUSED(next);
return TRUE;
}
|
