TT#100200 suppress audio packets during a DTMF event

Change-Id: I9612d692c3c6945c93b3194760383e67e5bca0e0

daemon/codec.c

@@ -123,6 +123,8 @@ struct codec_ssrc_handler {
 	// silence detection
 	GQueue silence_events;
 
+	// DTMF audio suppression
+	unsigned long dtmf_start_ts;
 	// DTMF send delay
 	unsigned long dtmf_first_duration;
 
@@ -2069,6 +2071,12 @@ static int packet_dtmf(struct codec_ssrc_handler *ch, struct transcode_packet *p
 		if (ret == 1) {
 			// END event
 			ch->ts_in = packet->ts;
+			if (decoder_ch)
+				decoder_ch->dtmf_start_ts = 0;
+		}
+		else {
+			if (decoder_ch)
+				decoder_ch->dtmf_start_ts = packet->ts ? packet->ts : 1;
 		}
 	}
 
@@ -2962,10 +2970,32 @@ static int packet_decode(struct codec_ssrc_handler *ch, struct transcode_packet
 {
 	int ret = 0;
 
+	struct codec_ssrc_handler *decoder_ch = ch;
+
+	if (ch->handler && ch->handler->source_pt.codec_def && ch->handler->source_pt.codec_def->supplemental) {
+		struct codec_handler *decoder_handler = __decoder_handler(ch->handler, mp);
+		decoder_ch = get_ssrc(mp->ssrc_in->parent->h.ssrc,
+				decoder_handler->ssrc_hash);
+	}
+
 	if (!ch->first_ts)
 		ch->first_ts = packet->ts;
 	ch->last_ts = packet->ts;
 
+	if (decoder_ch->dtmf_start_ts && !rtpe_config.dtmf_no_suppress) {
+		if ((packet->ts > decoder_ch->dtmf_start_ts && packet->ts - decoder_ch->dtmf_start_ts > 80000) ||
+				(packet->ts < decoder_ch->dtmf_start_ts && decoder_ch->dtmf_start_ts - packet->ts > 80000)) {
+			ilogs(transcoding, LOG_DEBUG, "Resetting decoder DTMF state due to TS discrepancy");
+			decoder_ch->dtmf_start_ts = 0;
+		}
+		else {
+			ilogs(transcoding, LOG_DEBUG, "Decoder is in DTMF state, discaring codec packet");
+			if (mp->ssrc_out)
+				mp->ssrc_out->parent->seq_diff--;
+			goto out;
+		}
+	}
+
 	if (__buffer_dtx(ch->dtx_buffer, ch, packet, mp, __rtp_decode))
 		ret = 1; // consumed
 	else {
@@ -2974,6 +3004,9 @@ static int packet_decode(struct codec_ssrc_handler *ch, struct transcode_packet
 		ret = ret ? -1 : 0;
 	}
 
+out:
+	if (decoder_ch != ch)
+		obj_put(&decoder_ch->h);
 	return ret;
 }
 

daemon/dtmf.c

@@ -122,7 +122,7 @@ int dtmf_event(struct media_packet *mp, str *payload, int clockrate) {
 	ilog(LOG_DEBUG, "DTMF event: event %u, volume %u, end %u, duration %u",
 			dtmf->event, dtmf->volume, dtmf->end, dtmf->duration);
 
-	int ret = 0;
+	int ret = dtmf->end ? 1 : 0;
 
 	GString *buf = NULL;
 
@@ -140,8 +140,6 @@ int dtmf_event(struct media_packet *mp, str *payload, int clockrate) {
 		if (rtpe_config.dtmf_via_ng)
 			dtmf_bencode_and_notify(mp, dtmf, clockrate);
 		g_string_free(buf, TRUE);
-
-		ret = 1; // END event
 	}
 
 	return ret;

daemon/main.c

@@ -432,6 +432,7 @@ static void options(int *argc, char ***argv) {
 		{ "log-facility-dtmf",0,  0, G_OPTION_ARG_STRING, &log_facility_dtmf_s, "Syslog facility to use for logging DTMF", "daemon|local0|...|local7"},
 		{ "dtmf-log-dest", 0,0,	G_OPTION_ARG_STRING,	&dtmf_udp_ep,	"Destination address for DTMF logging via UDP",	"IP46|HOSTNAME:PORT"	},
 		{ "dtmf-log-ng-tcp", 0,0,	G_OPTION_ARG_NONE,	&rtpe_config.dtmf_via_ng,	"DTMF logging via TCP NG protocol",	NULL },
+		{ "dtmf-no-suppress", 0,0,G_OPTION_ARG_NONE,	&rtpe_config.dtmf_no_suppress,	"Disable audio suppression during DTMF events",	NULL },
 #endif
 		{ "log-format",	0, 0,	G_OPTION_ARG_STRING,	&log_format,	"Log prefix format",		"default|parsable"},
 		{ "xmlrpc-format",'x', 0, G_OPTION_ARG_INT,	&rtpe_config.fmt,	"XMLRPC timeout request format to use. 0: SEMS DI, 1: call-id only, 2: Kamailio",	"INT"	},

daemon/rtpengine.pod

@@ -279,6 +279,14 @@ given address as UDP packets.
 If B<--listen-tcp-ng> is enabled, this will send DTMF events to all
 connected cliens encoded in bencode format.
 
+=item B<--dtmf-no-suppress>
+
+Some RTP clients continue to send audio RTP packets during a DTMF event,
+resulting in both audio packets and DTMF packets appearing simultaneously. By
+default, when transcoding, B<rtpengine> suppresses audio packets during a DTMF
+event and will only send DTMF packets until the DTMF event is over. Setting
+this option disables this feature.
+
 =item B<--log-srtp-keys>
 
 Write SRTP keys to error log instead of debug log.

include/main.h

@@ -97,6 +97,7 @@ struct rtpengine_config {
 	char			*mysql_query;
 	endpoint_t		dtmf_udp_ep;
 	int			dtmf_via_ng;
+	int			dtmf_no_suppress;
 	enum endpoint_learning	endpoint_learning;
 	int                     jb_length;
 	int                     jb_clock_drift;