mod_spandsp: improve duplicate digit detection and add 'min_dup_digit_spacing_ms...

diff --git a/src/mod/applications/mod_spandsp/mod_spandsp_dsp.c b/src/mod/applications/mod_spandsp/mod_spandsp_dsp.c
index bb9fd6a2c564f03561f316c25392811bcadcbcc4..92d29beaf6890fecec9f94f81920bed8ab45d911 100644 (file)
--- a/src/mod/applications/mod_spandsp/mod_spandsp_dsp.c
+++ b/src/mod/applications/mod_spandsp/mod_spandsp_dsp.c
@@ -36,41 +36,63 @@
 
 typedef struct {
        switch_core_session_t *session;
-    dtmf_rx_state_t *dtmf_detect;
+       dtmf_rx_state_t *dtmf_detect;
+       char last_digit;
+       uint32_t samples;
+       uint32_t last_digit_end;
+       uint32_t digit_begin;
+       uint32_t min_dup_digit_spacing;
 } switch_inband_dtmf_t;
 
+static void spandsp_dtmf_rx_realtime_callback(void *user_data, int code, int level, int delay)
+{
+       switch_inband_dtmf_t *pvt = (switch_inband_dtmf_t *)user_data;
+       char digit = (char)code;
+       if (digit) {
+               /* prevent duplicate DTMF */
+               if (digit != pvt->last_digit || (pvt->samples - pvt->last_digit_end) > pvt->min_dup_digit_spacing) {
+                       switch_dtmf_t dtmf;
+                       switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(pvt->session), SWITCH_LOG_DEBUG, "DTMF BEGIN DETECTED: [%c]\n", digit);
+                       pvt->last_digit = digit;
+                       dtmf.digit = digit;
+                       dtmf.duration = switch_core_default_dtmf_duration(0);
+                       switch_channel_queue_dtmf(switch_core_session_get_channel(pvt->session), &dtmf);
+                       pvt->digit_begin = pvt->samples;
+               } else {
+                       switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(pvt->session), SWITCH_LOG_DEBUG, "DUP DTMF DETECTED: [%c]\n", digit);
+                       pvt->last_digit_end = pvt->samples;
+               }
+       } else {
+               switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(pvt->session), SWITCH_LOG_DEBUG, "DTMF END DETECTED: [%c], duration = %u ms\n", pvt->last_digit, (pvt->samples - pvt->digit_begin) / 8);
+               pvt->last_digit_end = pvt->samples;
+       }
+}
+
 static switch_bool_t inband_dtmf_callback(switch_media_bug_t *bug, void *user_data, switch_abc_type_t type)
 {
        switch_inband_dtmf_t *pvt = (switch_inband_dtmf_t *) user_data;
        switch_frame_t *frame = NULL;
-       char digit_str[80];
        switch_channel_t *channel = switch_core_session_get_channel(pvt->session);
 
        switch (type) {
-       case SWITCH_ABC_TYPE_INIT:
-        pvt->dtmf_detect = dtmf_rx_init(NULL, NULL, NULL);
+       case SWITCH_ABC_TYPE_INIT: {
+               const char *min_dup_digit_spacing_str = switch_channel_get_variable(channel, "min_dup_digit_spacing_ms");
+               pvt->dtmf_detect = dtmf_rx_init(NULL, NULL, NULL);
+               dtmf_rx_set_realtime_callback(pvt->dtmf_detect, spandsp_dtmf_rx_realtime_callback, pvt);
+               if (!zstr(min_dup_digit_spacing_str)) {
+                       pvt->min_dup_digit_spacing = atoi(min_dup_digit_spacing_str) * 8;
+               }
                break;
+       }
        case SWITCH_ABC_TYPE_CLOSE:
-        if (pvt->dtmf_detect) {
-            dtmf_rx_free(pvt->dtmf_detect);
-        }
+               if (pvt->dtmf_detect) {
+                       dtmf_rx_free(pvt->dtmf_detect);
+               }
                break;
        case SWITCH_ABC_TYPE_READ_REPLACE:
                if ((frame = switch_core_media_bug_get_read_replace_frame(bug))) {
+                       pvt->samples += frame->samples;
                        dtmf_rx(pvt->dtmf_detect, frame->data, frame->samples);
-                       dtmf_rx_get(pvt->dtmf_detect, digit_str, sizeof(digit_str));
-                       if (digit_str[0]) {
-                               char *p = digit_str;
-                               while (p && *p) {
-                                       switch_dtmf_t dtmf;
-                                       dtmf.digit = *p;
-                                       dtmf.duration = switch_core_default_dtmf_duration(0);
-                                       switch_channel_queue_dtmf(channel, &dtmf);
-                                       p++;
-                               }
-                               switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(switch_core_media_bug_get_session(bug)), SWITCH_LOG_DEBUG, "DTMF DETECTED: [%s]\n",
-                                                                 digit_str);
-                       }
                        switch_core_media_bug_set_read_replace_frame(bug, frame);
                }
                break;