FS-11443 [core] reworked switch_vad.c and added voice_ms and silence_ms as parameters.

diff --git a/src/switch_vad.c b/src/switch_vad.c
index 1608a335432c6ad3923bdb1cc2ff4c01de020a48..9e7ab0f773eac3d27809a1f8a7fd2bbd79a0a151 100644 (file)
--- a/src/switch_vad.c
+++ b/src/switch_vad.c
@@ -37,20 +37,18 @@
 #endif
 
 struct switch_vad_s {
-       int talking;
-       int talked;
-       int talk_hits;
-       int listen_hits;
-       int hangover;
-       int hangover_len;
-       int divisor;
-       int thresh;
+       // configs
        int channels;
        int sample_rate;
        int debug;
-       int _hangover_len;
-       int _thresh;
-       int _listen_hits;
+       int divisor;
+       int thresh;
+       int voice_samples_thresh;
+       int silence_samples_thresh;
+
+       // VAD state
+       int voice_samples;
+       int silence_samples;
        switch_vad_state_t vad_state;
 #ifdef SWITCH_HAVE_FVAD
        Fvad *fvad;
@@ -82,9 +80,13 @@ SWITCH_DECLARE(switch_vad_t *) switch_vad_init(int sample_rate, int channels)
        memset(vad, 0, sizeof(*vad));
        vad->sample_rate = sample_rate ? sample_rate : 8000;
        vad->channels = channels;
-       vad->_hangover_len = 25;
-       vad->_thresh = 100;
-       vad->_listen_hits = 10;
+       vad->silence_samples_thresh = 500 * (vad->sample_rate / 1000);
+       vad->voice_samples_thresh = 200 * (vad->sample_rate / 1000);
+       vad->thresh = 100;
+       vad->divisor = vad->sample_rate / 8000;
+       if (vad->divisor <= 0) {
+               vad->divisor = 1;
+       }
        switch_vad_reset(vad);
 
        return vad;
@@ -129,13 +131,29 @@ SWITCH_DECLARE(void) switch_vad_set_param(switch_vad_t *vad, const char *key, in
        if (!key) return;
 
        if (!strcmp(key, "hangover_len")) {
-               vad->hangover_len = vad->_hangover_len = val;
+               /* convert old-style hits to samples assuming 20ms ptime */
+               switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "hangover_len is deprecated, setting silence_ms to %d\n", 20 * val);
+               switch_vad_set_param(vad, "silence_ms", val * 20);
+       } else if (!strcmp(key, "silence_ms")) {
+               if (val > 0) {
+                       vad->silence_samples_thresh = val * (vad->sample_rate / 1000);
+               } else {
+                       switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Ignoring invalid silence_ms of %d\n", val);
+               }
        } else if (!strcmp(key, "thresh")) {
-               vad->thresh = vad->_thresh = val;
+               vad->thresh = val;
        } else if (!strcmp(key, "debug")) {
                vad->debug = val;
+       } else if (!strcmp(key, "voice_ms")) {
+               if (val > 0) {
+                       vad->voice_samples_thresh = val * (vad->sample_rate / 1000);
+               } else {
+                       switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Ignoring invalid voice_ms of %d\n", val);
+               }
        } else if (!strcmp(key, "listen_hits")) {
-               vad->listen_hits = vad->_listen_hits = val;
+               /* convert old-style hits to samples assuming 20ms ptime */
+               switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "listen_hits is deprecated, setting voice_ms to %d\n", 20 * val);
+               switch_vad_set_param(vad, "voice_ms", 20 * val);
        }
 }
 
@@ -144,34 +162,23 @@ SWITCH_DECLARE(void) switch_vad_reset(switch_vad_t *vad)
 #ifdef SWITCH_HAVE_FVAD
        if (vad->fvad) {
                fvad_reset(vad->fvad);
-               return;
        }
 #endif
-
-       vad->talking = 0;
-       vad->talked = 0;
-       vad->talk_hits = 0;
-       vad->hangover = 0;
-       vad->listen_hits = vad->_listen_hits;
-       vad->hangover_len = vad->_hangover_len;
-       vad->divisor = vad->sample_rate / 8000;
-       vad->thresh = vad->_thresh;
        vad->vad_state = SWITCH_VAD_STATE_NONE;
+       vad->voice_samples = 0;
+       vad->silence_samples = 0;
 }
 
 SWITCH_DECLARE(switch_vad_state_t) switch_vad_process(switch_vad_t *vad, int16_t *data, unsigned int samples)
 {
-       int energy = 0, j = 0, count = 0;
        int score = 0;
 
-       if (vad->vad_state == SWITCH_VAD_STATE_STOP_TALKING) {
-               vad->vad_state = SWITCH_VAD_STATE_NONE;
-       }
+       // Each frame has 2 possible outcomes- voice or not voice.
+       // The VAD has 2 real states- talking / not talking with
+       // begin talking and stop talking as events to mark transitions
 
-       if (vad->vad_state == SWITCH_VAD_STATE_START_TALKING) {
-               vad->vad_state = SWITCH_VAD_STATE_TALKING;
-       }
-       
+
+       // determine if this is a voice or non-voice frame
 #ifdef SWITCH_HAVE_FVAD
        if (vad->fvad) {
                int ret = fvad_process(vad->fvad, data, samples);
@@ -181,60 +188,40 @@ SWITCH_DECLARE(switch_vad_state_t) switch_vad_process(switch_vad_t *vad, int16_t
                score = vad->thresh + ret - 1;
        } else {
 #endif
+               int energy = 0, j = 0, count = 0;
+               for (energy = 0, j = 0, count = 0; count < samples; count++) {
+                       energy += abs(data[j]);
+                       j += vad->channels;
+               }
 
-       for (energy = 0, j = 0, count = 0; count < samples; count++) {
-               energy += abs(data[j]);
-               j += vad->channels;
-       }
-
-       score = (uint32_t) (energy / (samples / vad->divisor));
-
+               score = (uint32_t) (energy / (samples / vad->divisor));
 #ifdef SWITCH_HAVE_FVAD
        }
 #endif
 
-       //printf("%d ", score); fflush(stdout);
-       //printf("yay %d %d %d\n", score, vad->hangover, vad->talking);
-
-       if (vad->talking && score < vad->thresh) {
-               if (vad->hangover > 0) {
-                       vad->hangover--;
-               } else {// if (hangover <= 0) {
-                       vad->talking = 0;
-                       vad->talk_hits = 0;
-                       vad->hangover = 0;
-               }
-       } else {
-               if (score >= vad->thresh) {
-                       vad->vad_state = vad->talking ? SWITCH_VAD_STATE_TALKING : SWITCH_VAD_STATE_START_TALKING;
-                       vad->talking = 1;
-                       vad->hangover = vad->hangover_len;
-               }
+       // clear the STOP/START TALKING events
+       if (vad->vad_state == SWITCH_VAD_STATE_STOP_TALKING) {
+               vad->vad_state = SWITCH_VAD_STATE_NONE;
+       } else if (vad->vad_state == SWITCH_VAD_STATE_START_TALKING) {
+               vad->vad_state = SWITCH_VAD_STATE_TALKING;
        }
 
-       // printf("WTF %d %d %d\n", score, vad->talked, vad->talking);
-
-       if (vad->talking) {
-               vad->talk_hits++;
-               // printf("WTF %d %d %d\n", vad->talking, vad->talk_hits, vad->talked);
-               if (vad->talk_hits > vad->listen_hits) {
-                       vad->talked = 1;
-                       vad->vad_state = SWITCH_VAD_STATE_TALKING;
-               }
+       // adjust voice/silence run length counters
+       if (score > vad->thresh) {
+               vad->silence_samples = 0;
+               vad->voice_samples += samples;
        } else {
-               vad->talk_hits = 0;
+               vad->silence_samples += samples;
+               vad->voice_samples = 0;
        }
 
-       if ((vad->talked && !vad->talking)) {
-               // printf("NOT TALKING ANYMORE\n");
-               vad->talked = 0;
+       // check for state transitions
+       if (vad->vad_state == SWITCH_VAD_STATE_TALKING && vad->silence_samples > vad->silence_samples_thresh) {
                vad->vad_state = SWITCH_VAD_STATE_STOP_TALKING;
+       } else if (vad->vad_state == SWITCH_VAD_STATE_NONE && vad->voice_samples > vad->voice_samples_thresh) {
+               vad->vad_state = SWITCH_VAD_STATE_START_TALKING;
        }
 
-       if (vad->debug > 0) {
-               switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "VAD DEBUG energy: %d state %s\n", score, switch_vad_state2str(vad->vad_state));
-       }
-       
        return vad->vad_state;
 }