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
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
|
/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2013, Digium, Inc.
*
* Lorenzo Miniero <lorenzo@meetecho.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*!
* \file
* \brief Opus format attribute interface
*
* \author Lorenzo Miniero <lorenzo@meetecho.com>
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
#include "asterisk/module.h"
#include "asterisk/format.h"
/*!
* \brief Opus attribute structure.
*
* \note http://tools.ietf.org/html/draft-ietf-payload-rtp-opus-00.
*/
struct opus_attr {
unsigned int maxbitrate; /* Default 64-128 kb/s for FB stereo music */
unsigned int maxplayrate /* Default 48000 */;
unsigned int minptime; /* Default 3, but it's 10 in format.c */
unsigned int stereo; /* Default 0 */
unsigned int cbr; /* Default 0 */
unsigned int fec; /* Default 0 */
unsigned int dtx; /* Default 0 */
unsigned int spropmaxcapturerate; /* Default 48000 */
unsigned int spropstereo; /* Default 0 */
};
static int opus_sdp_parse(struct ast_format_attr *format_attr, const char *attributes)
{
struct opus_attr *attr = (struct opus_attr *) format_attr;
const char *kvp;
unsigned int val;
if ((kvp = strstr(attributes, "maxplaybackrate")) && sscanf(kvp, "maxplaybackrate=%30u", &val) == 1) {
attr->maxplayrate = val;
}
if ((kvp = strstr(attributes, "sprop-maxcapturerate")) && sscanf(kvp, "sprop-maxcapturerate=%30u", &val) == 1) {
attr->spropmaxcapturerate = val;
}
if ((kvp = strstr(attributes, "minptime")) && sscanf(kvp, "minptime=%30u", &val) == 1) {
attr->minptime = val;
}
if ((kvp = strstr(attributes, "maxaveragebitrate")) && sscanf(kvp, "maxaveragebitrate=%30u", &val) == 1) {
attr->maxbitrate = val;
}
if ((kvp = strstr(attributes, " stereo")) && sscanf(kvp, " stereo=%30u", &val) == 1) {
attr->stereo = val;
}
if ((kvp = strstr(attributes, ";stereo")) && sscanf(kvp, ";stereo=%30u", &val) == 1) {
attr->stereo = val;
}
if ((kvp = strstr(attributes, "sprop-stereo")) && sscanf(kvp, "sprop-stereo=%30u", &val) == 1) {
attr->spropstereo = val;
}
if ((kvp = strstr(attributes, "cbr")) && sscanf(kvp, "cbr=%30u", &val) == 1) {
attr->cbr = val;
}
if ((kvp = strstr(attributes, "useinbandfec")) && sscanf(kvp, "useinbandfec=%30u", &val) == 1) {
attr->fec = val;
}
if ((kvp = strstr(attributes, "usedtx")) && sscanf(kvp, "usedtx=%30u", &val) == 1) {
attr->dtx = val;
}
return 0;
}
static void opus_sdp_generate(const struct ast_format_attr *format_attr, unsigned int payload, struct ast_str **str)
{
struct opus_attr *attr = (struct opus_attr *) format_attr;
/* FIXME should we only generate attributes that were explicitly set? */
ast_str_append(str, 0,
"a=fmtp:%d "
"maxplaybackrate=%d;"
"sprop-maxcapturerate=%d;"
"minptime=%d;"
"maxaveragebitrate=%d;"
"stereo=%d;"
"sprop-stereo=%d;"
"cbr=%d;"
"useinbandfec=%d;"
"usedtx=%d\r\n",
payload,
attr->maxplayrate ? attr->maxplayrate : 48000, /* maxplaybackrate */
attr->spropmaxcapturerate ? attr->spropmaxcapturerate : 48000, /* sprop-maxcapturerate */
attr->minptime > 10 ? attr->minptime : 10, /* minptime */
attr->maxbitrate ? attr->maxbitrate : 20000, /* maxaveragebitrate */
attr->stereo ? 1 : 0, /* stereo */
attr->spropstereo ? 1 : 0, /* sprop-stereo */
attr->cbr ? 1 : 0, /* cbr */
attr->fec ? 1 : 0, /* useinbandfec */
attr->dtx ? 1 : 0 /* usedtx */
);
}
static int opus_get_val(const struct ast_format_attr *fattr, int key, void *result)
{
const struct opus_attr *attr = (struct opus_attr *) fattr;
int *val = result;
switch (key) {
case OPUS_ATTR_KEY_MAX_BITRATE:
*val = attr->maxbitrate;
break;
case OPUS_ATTR_KEY_MAX_PLAYRATE:
*val = attr->maxplayrate;
break;
case OPUS_ATTR_KEY_MINPTIME:
*val = attr->minptime;
break;
case OPUS_ATTR_KEY_STEREO:
*val = attr->stereo;
break;
case OPUS_ATTR_KEY_CBR:
*val = attr->cbr;
break;
case OPUS_ATTR_KEY_FEC:
*val = attr->fec;
break;
case OPUS_ATTR_KEY_DTX:
*val = attr->dtx;
break;
case OPUS_ATTR_KEY_SPROP_CAPTURE_RATE:
*val = attr->spropmaxcapturerate;
break;
case OPUS_ATTR_KEY_SPROP_STEREO:
*val = attr->spropstereo;
break;
default:
ast_log(LOG_WARNING, "unknown attribute type %d\n", key);
return -1;
}
return 0;
}
static int opus_isset(const struct ast_format_attr *fattr, va_list ap)
{
enum opus_attr_keys key;
const struct opus_attr *attr = (struct opus_attr *) fattr;
for (key = va_arg(ap, int);
key != AST_FORMAT_ATTR_END;
key = va_arg(ap, int))
{
switch (key) {
case OPUS_ATTR_KEY_MAX_BITRATE:
if (attr->maxbitrate != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_MAX_PLAYRATE:
if (attr->maxplayrate != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_MINPTIME:
if (attr->minptime != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_STEREO:
if (attr->stereo != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_CBR:
if (attr->cbr != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_FEC:
if (attr->fec != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_DTX:
if (attr->dtx != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_SPROP_CAPTURE_RATE:
if (attr->spropmaxcapturerate != (va_arg(ap, int))) {
return -1;
}
break;
case OPUS_ATTR_KEY_SPROP_STEREO:
if (attr->spropstereo != (va_arg(ap, int))) {
return -1;
}
break;
default:
ast_log(LOG_WARNING, "unknown attribute type %d\n", key);
return -1;
}
}
return 0;
}
static int opus_getjoint(const struct ast_format_attr *fattr1, const struct ast_format_attr *fattr2, struct ast_format_attr *result)
{
struct opus_attr *attr1 = (struct opus_attr *) fattr1;
struct opus_attr *attr2 = (struct opus_attr *) fattr2;
struct opus_attr *attr_res = (struct opus_attr *) result;
int joint = 0;
/* Only do dtx if both sides want it. DTX is a trade off between
* computational complexity and bandwidth. */
attr_res->dtx = attr1->dtx && attr2->dtx ? 1 : 0;
/* Only do FEC if both sides want it. If a peer specifically requests not
* to receive with FEC, it may be a waste of bandwidth. */
attr_res->fec = attr1->fec && attr2->fec ? 1 : 0;
/* Only do stereo if both sides want it. If a peer specifically requests not
* to receive stereo signals, it may be a waste of bandwidth. */
attr_res->stereo = attr1->stereo && attr2->stereo ? 1 : 0;
/* FIXME: do we need to join other attributes as well, e.g., minptime, cbr, etc.? */
return joint;
}
static void opus_set(struct ast_format_attr *fattr, va_list ap)
{
enum opus_attr_keys key;
struct opus_attr *attr = (struct opus_attr *) fattr;
for (key = va_arg(ap, int);
key != AST_FORMAT_ATTR_END;
key = va_arg(ap, int))
{
switch (key) {
case OPUS_ATTR_KEY_MAX_BITRATE:
attr->maxbitrate = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_MAX_PLAYRATE:
attr->maxplayrate = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_MINPTIME:
attr->minptime = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_STEREO:
attr->stereo = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_CBR:
attr->cbr = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_FEC:
attr->fec = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_DTX:
attr->dtx = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_SPROP_CAPTURE_RATE:
attr->spropmaxcapturerate = (va_arg(ap, int));
break;
case OPUS_ATTR_KEY_SPROP_STEREO:
attr->spropstereo = (va_arg(ap, int));
break;
default:
ast_log(LOG_WARNING, "unknown attribute type %d\n", key);
}
}
}
static struct ast_format_attr_interface opus_interface = {
.id = AST_FORMAT_OPUS,
.format_attr_get_joint = opus_getjoint,
.format_attr_set = opus_set,
.format_attr_isset = opus_isset,
.format_attr_get_val = opus_get_val,
.format_attr_sdp_parse = opus_sdp_parse,
.format_attr_sdp_generate = opus_sdp_generate,
};
static int load_module(void)
{
if (ast_format_attr_reg_interface(&opus_interface)) {
return AST_MODULE_LOAD_DECLINE;
}
return AST_MODULE_LOAD_SUCCESS;
}
static int unload_module(void)
{
ast_format_attr_unreg_interface(&opus_interface);
return 0;
}
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "Opus Format Attribute Module",
.load = load_module,
.unload = unload_module,
.load_pri = AST_MODPRI_CHANNEL_DEPEND,
);
|
