forked from seanbright/mod_amd
-
Notifications
You must be signed in to change notification settings - Fork 1
/
mod_amd.c
427 lines (350 loc) · 10.3 KB
/
mod_amd.c
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
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
#include <switch.h>
#define AMD_PARAMS (2)
#define AMD_SYNTAX "<uuid> <command>"
SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_amd_shutdown);
SWITCH_MODULE_LOAD_FUNCTION(mod_amd_load);
SWITCH_MODULE_DEFINITION(mod_amd, mod_amd_load, mod_amd_shutdown, NULL);
SWITCH_STANDARD_APP(amd_start_function);
static struct {
uint32_t initial_silence;
uint32_t greeting;
uint32_t after_greeting_silence;
uint32_t total_analysis_time;
uint32_t minimum_word_length;
uint32_t between_words_silence;
uint32_t maximum_number_of_words;
uint32_t silence_threshold;
uint32_t maximum_word_length;
} globals;
static switch_xml_config_item_t instructions[] = {
SWITCH_CONFIG_ITEM(
"initial_silence",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.initial_silence,
(void *) 2500,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"greeting",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.greeting,
(void *) 1500,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"after_greeting_silence",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.after_greeting_silence,
(void *) 800,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"total_analysis_time",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.total_analysis_time,
(void *) 5000,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"min_word_length",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.minimum_word_length,
(void *) 100,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"between_words_silence",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.between_words_silence,
(void *) 50,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"maximum_number_of_words",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.maximum_number_of_words,
(void *) 3,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"maximum_word_length",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.maximum_word_length,
(void *)5000,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM(
"silence_threshold",
SWITCH_CONFIG_INT,
CONFIG_RELOADABLE,
&globals.silence_threshold,
(void *) 256,
NULL, NULL, NULL),
SWITCH_CONFIG_ITEM_END()
};
static switch_status_t do_config(switch_bool_t reload)
{
memset(&globals, 0, sizeof(globals));
if (switch_xml_config_parse_module_settings("amd.conf", reload, instructions) != SWITCH_STATUS_SUCCESS) {
return SWITCH_STATUS_FALSE;
}
return SWITCH_STATUS_SUCCESS;
}
SWITCH_MODULE_LOAD_FUNCTION(mod_amd_load)
{
switch_application_interface_t *app_interface;
*module_interface = switch_loadable_module_create_module_interface(pool, modname);
do_config(SWITCH_FALSE);
SWITCH_ADD_APP(
app_interface,
"amd",
"Voice activity detection (blocking)",
"Asterisk's AMD (Blocking)",
amd_start_function,
NULL,
SAF_NONE);
return SWITCH_STATUS_SUCCESS;
}
SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_amd_shutdown)
{
switch_xml_config_cleanup(instructions);
return SWITCH_STATUS_SUCCESS;
}
typedef enum {
SILENCE,
VOICED
} amd_frame_classifier;
typedef enum {
VAD_STATE_IN_WORD,
VAD_STATE_IN_SILENCE,
} amd_vad_state_t;
typedef struct {
const switch_core_session_t *session;
switch_channel_t *channel;
amd_vad_state_t state;
uint32_t frame_ms;
uint32_t silence_duration;
uint32_t voice_duration;
uint32_t words;
uint32_t in_initial_silence:1;
uint32_t in_greeting:1;
} amd_vad_t;
static amd_frame_classifier classify_frame(const switch_frame_t *f, const switch_codec_implementation_t *codec)
{
int16_t *audio = f->data;
uint32_t score, count, j;
double energy;
int divisor;
divisor = codec->actual_samples_per_second / 8000;
for (energy = 0, j = 0, count = 0; count < f->samples; count++) {
energy += abs(audio[j++]);
j += codec->number_of_channels;
}
score = (uint32_t) (energy / (f->samples / divisor));
if (score >= globals.silence_threshold) {
return VOICED;
}
return SILENCE;
}
static switch_bool_t amd_handle_silence_frame(amd_vad_t *vad, const switch_frame_t *f)
{
vad->silence_duration += vad->frame_ms;
if (vad->silence_duration >= globals.between_words_silence) {
if (vad->state != VAD_STATE_IN_SILENCE) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: Changed state to VAD_STATE_IN_SILENCE\n");
}
vad->state = VAD_STATE_IN_SILENCE;
vad->voice_duration = 0;
}
if (vad->in_initial_silence && vad->silence_duration >= globals.initial_silence) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: MACHINE (silence_duration: %d, initial_silence: %d)\n",
vad->silence_duration,
globals.initial_silence);
switch_channel_set_variable(vad->channel, "amd_result", "MACHINE");
switch_channel_set_variable(vad->channel, "amd_cause", "INITIALSILENCE");
return SWITCH_TRUE;
}
if (vad->silence_duration >= globals.after_greeting_silence && vad->in_greeting) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: HUMAN (silence_duration: %d, after_greeting_silence: %d)\n",
vad->silence_duration,
globals.after_greeting_silence);
switch_channel_set_variable(vad->channel, "amd_result", "HUMAN");
switch_channel_set_variable(vad->channel, "amd_cause", "HUMAN");
return SWITCH_TRUE;
}
return SWITCH_FALSE;
}
static switch_bool_t amd_handle_voiced_frame(amd_vad_t *vad, const switch_frame_t *f)
{
vad->voice_duration += vad->frame_ms;
if (vad->voice_duration >= globals.minimum_word_length && vad->state == VAD_STATE_IN_SILENCE) {
vad->words++;
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: Word detected (words: %d)\n",
vad->words);
vad->state = VAD_STATE_IN_WORD;
}
if (vad->voice_duration >= globals.maximum_word_length) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: MACHINE (voice_duration: %d, maximum_word_length: %d)\n",
vad->voice_duration,
globals.maximum_word_length);
switch_channel_set_variable(vad->channel, "amd_result", "MACHINE");
switch_channel_set_variable(vad->channel, "amd_cause", "MAXWORDLENGTH");
return SWITCH_TRUE;
}
if (vad->words >= globals.maximum_number_of_words) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: MACHINE (words: %d, maximum_number_of_words: %d)\n",
vad->words,
globals.maximum_number_of_words);
switch_channel_set_variable(vad->channel, "amd_result", "MACHINE");
switch_channel_set_variable(vad->channel, "amd_cause", "MAXWORDS");
return SWITCH_TRUE;
}
if (vad->in_greeting && vad->voice_duration >= globals.greeting) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: MACHINE (voice_duration: %d, greeting: %d)\n",
vad->voice_duration,
globals.greeting);
switch_channel_set_variable(vad->channel, "amd_result", "MACHINE");
switch_channel_set_variable(vad->channel, "amd_cause", "LONGGREETING");
return SWITCH_TRUE;
}
if (vad->voice_duration >= globals.minimum_word_length) {
if (vad->silence_duration) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: Detected Talk, previous silence duration: %dms\n",
vad->silence_duration);
}
vad->silence_duration = 0;
}
if (vad->voice_duration >= globals.minimum_word_length && !vad->in_greeting) {
if (vad->silence_duration) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(vad->session),
SWITCH_LOG_DEBUG,
"AMD: Before Greeting Time (silence_duration: %d, voice_duration: %d)\n",
vad->silence_duration,
vad->voice_duration);
}
vad->in_initial_silence = 0;
vad->in_greeting = 1;
}
return SWITCH_FALSE;
}
SWITCH_STANDARD_APP(amd_start_function)
{
switch_channel_t *channel = switch_core_session_get_channel(session);
switch_codec_t raw_codec = { 0 };
switch_codec_implementation_t read_impl = { 0 };
switch_frame_t *read_frame;
switch_status_t status;
uint32_t timeout_ms = globals.total_analysis_time;
int32_t sample_count_limit;
switch_bool_t complete = SWITCH_FALSE;
amd_vad_t vad = { 0 };
if (!session) {
return;
}
vad.channel = channel;
vad.session = session;
vad.state = VAD_STATE_IN_WORD;
vad.silence_duration = 0;
vad.voice_duration = 0;
vad.frame_ms = 0;
vad.in_initial_silence = 1;
vad.in_greeting = 0;
vad.words = 0;
switch_core_session_get_read_impl(session, &read_impl);
if (timeout_ms) {
sample_count_limit = (read_impl.actual_samples_per_second / 1000) * timeout_ms;
}
/*
* We are creating a new L16 (raw 16-bit samples) codec for the read end
* of our channel. We'll use this to process the audio coming off of the
* channel so that we always know what we are dealing with.
*/
status = switch_core_codec_init(
&raw_codec,
"L16",
NULL,
read_impl.actual_samples_per_second,
read_impl.microseconds_per_packet / 1000,
1,
SWITCH_CODEC_FLAG_ENCODE | SWITCH_CODEC_FLAG_DECODE,
NULL,
switch_core_session_get_pool(session));
if (status != SWITCH_STATUS_SUCCESS) {
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(session),
SWITCH_LOG_ERROR,
"Unable to initialize L16 (raw) codec.\n");
return;
}
switch_core_session_set_read_codec(session, &raw_codec);
while (switch_channel_ready(channel)) {
status = switch_core_session_read_frame(session, &read_frame, SWITCH_IO_FLAG_NONE, 0);
if (!SWITCH_READ_ACCEPTABLE(status)) {
break;
}
if (read_frame->samples == 0) {
continue;
}
vad.frame_ms = 1000 / (read_impl.actual_samples_per_second / read_frame->samples);
if (sample_count_limit) {
sample_count_limit -= raw_codec.implementation->samples_per_packet;
if (sample_count_limit <= 0) {
switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "AMD: Timeout\n");
switch_channel_set_variable(channel, "amd_result", "NOTSURE");
switch_channel_set_variable(channel, "amd_cause", "TOOLONG");
break;
}
}
switch (classify_frame(read_frame, &read_impl)) {
case SILENCE:
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(session),
SWITCH_LOG_DEBUG,
"AMD: Silence\n");
if (amd_handle_silence_frame(&vad, read_frame)) {
complete = SWITCH_TRUE;
}
break;
case VOICED:
default:
switch_log_printf(
SWITCH_CHANNEL_SESSION_LOG(session),
SWITCH_LOG_DEBUG,
"AMD: Voiced\n");
if (amd_handle_voiced_frame(&vad, read_frame)) {
complete = SWITCH_TRUE;
}
break;
}
if (complete) {
break;
}
}
switch_core_session_reset(session, SWITCH_FALSE, SWITCH_TRUE);
switch_core_codec_destroy(&raw_codec);
}