TT#122401 add configurable CN method

Change-Id: I2aa9901b2a9dcf64563a84d77fa40d23b6c25525

daemon/codec.c

@@ -2835,6 +2835,8 @@ static struct ssrc_entry *__ssrc_handler_transcode_new(void *p) {
 			&ch->encoder_format, &h->source_pt.format_parameters, &h->source_pt.codec_opts);
 	if (!ch->decoder)
 		goto err;
+	if (rtpe_config.dtx_cn_params.len)
+		decoder_set_cn_dtx(ch->decoder, &rtpe_config.dtx_cn_params);
 
 	ch->decoder->event_data = h->media;
 	ch->decoder->event_func = codec_decoder_event;

daemon/main.c

@@ -363,6 +363,32 @@ static int redis_ep_parse(endpoint_t *ep, int *db, char **auth, const char *auth
 }
 
 
+static void parse_cn_payload(str *out, char **in, const char *def, const char *name) {
+	if (!in || !*in) {
+		if (def)
+			str_init_dup(out, def);
+		return;
+	}
+
+	int len = g_strv_length(in);
+	if (len < 1)
+		die("Invalid CN payload specified (--%s)", name);
+	out->s = malloc(len);
+	for (int i = 0; i < len; i++) {
+		char *endp;
+		long p = strtol(in[i], &endp, 0);
+		if (endp == in[i] || *endp != '\0')
+			die("Invalid CN payload specified (--%s)", name);
+		if (p < 0 || p > 254)
+			die("Invalid CN payload specified (--%s)", name);
+		if (i == 0 && p > 127)
+			die("Invalid CN payload specified (--%s)", name);
+		out->s[i] = p;
+	}
+	out->len = len;
+}
+
+
 
 static void options(int *argc, char ***argv) {
 	AUTO_CLEANUP_GVBUF(if_a);
@@ -395,6 +421,7 @@ static void options(int *argc, char ***argv) {
 	AUTO_CLEANUP_GBUF(dtls_sig);
 	double silence_detect = 0;
 	AUTO_CLEANUP_GVBUF(cn_payload);
+	AUTO_CLEANUP_GVBUF(dtx_cn_params);
 	int debug_srtp = 0;
 
 	rwlock_lock_w(&rtpe_config.config_lock);
@@ -494,6 +521,7 @@ static void options(int *argc, char ***argv) {
 		{ "dtx-buffer",	0,0,	G_OPTION_ARG_INT,	&rtpe_config.dtx_buffer,"Maxmium number of packets held in DTX buffer",	"INT"},
 		{ "dtx-lag",	0,0,	G_OPTION_ARG_INT,	&rtpe_config.dtx_lag,	"Maxmium time span in milliseconds held in DTX buffer",	"INT"},
 		{ "dtx-shift",	0,0,	G_OPTION_ARG_INT,	&rtpe_config.dtx_shift,	"Length of time (in ms) to shift DTX buffer after over/underflow",	"INT"},
+		{ "dtx-cn-params",0,0,	G_OPTION_ARG_STRING_ARRAY,&dtx_cn_params,	"Parameters for CN generated from DTX","INT INT INT ..."},
 		{ "silence-detect",0,0,	G_OPTION_ARG_DOUBLE,	&silence_detect,	"Audio level threshold in percent for silence detection","FLOAT"},
 		{ "cn-payload",0,0,	G_OPTION_ARG_STRING_ARRAY,&cn_payload,		"Comfort noise parameters to replace silence with","INT INT INT ..."},
 		{ "reorder-codecs",0,0,	G_OPTION_ARG_NONE,	&rtpe_config.reorder_codecs,"Reorder answer codecs based on sender preference",NULL},
@@ -737,26 +765,8 @@ static void options(int *argc, char ***argv) {
 		rtpe_config.silence_detect_int = (int) ((silence_detect / 100.0) * UINT32_MAX);
 	}
 
-	if (!cn_payload)
-		str_init_dup(&rtpe_config.cn_payload, "\x20");
-	else {
-		int len = g_strv_length(cn_payload);
-		if (len < 1)
-			die("Invalid CN payload specified");
-		rtpe_config.cn_payload.s = malloc(len);
-		for (int i = 0; i < len; i++) {
-			char *endp;
-			long p = strtol(cn_payload[i], &endp, 0);
-			if (endp == cn_payload[i] || *endp != '\0')
-				die("Invalid CN payload specified");
-			if (p < 0 || p > 254)
-				die("Invalid CN payload specified");
-			if (i == 0 && p > 127)
-				die("Invalid CN payload specified");
-			rtpe_config.cn_payload.s[i] = p;
-		}
-		rtpe_config.cn_payload.len = len;
-	}
+	parse_cn_payload(&rtpe_config.cn_payload, cn_payload, "\x20", "cn-payload");
+	parse_cn_payload(&rtpe_config.dtx_cn_params, dtx_cn_params, NULL, "dtx-cn-params");
 
 	if (!rtpe_config.software_id)
 		rtpe_config.software_id = g_strdup_printf("rtpengine-%s", RTPENGINE_VERSION);
@@ -895,6 +905,8 @@ static void options_free(void) {
 	g_free(rtpe_config.software_id);
 	if (rtpe_config.cn_payload.s)
 		free(rtpe_config.cn_payload.s);
+	if (rtpe_config.dtx_cn_params.s)
+		free(rtpe_config.dtx_cn_params.s);
 
 	// free common config options
 	config_load_free(&rtpe_config.common);

daemon/rtpengine.pod

@@ -785,13 +785,13 @@ non-alphanumeric characters with a dash to make it universally usable.
 =item B<--dtx-delay=>I<INT>
 
 Processing delay in milliseconds to handle discontinuous transmission (DTX) or
-other transmission gaps for codecs that support it (currently only AMR and
-AMR-WB). Defaults to zero (disabled) and applicable to transcoded audio streams
-only. When enabled, delays processing of received packets for the specified
-time (much like a jitter buffer) in order to trigger DTX handling when a
-transmission gap occurs. The decoder is then instructed to fill in the missing
-time during a transmission gap, for example by generating comfort noise. The
-delay should be configured to be higher than the expected incoming jitter.
+other transmission gaps. Defaults to zero (disabled) and is applicable to
+transcoded audio streams only. When enabled, delays processing of received
+packets for the specified time (much like a jitter buffer) in order to trigger
+DTX handling when a transmission gap occurs. The decoder is then instructed to
+fill in the missing time during a transmission gap, for example by generating
+comfort noise. The delay should be configured to be higher than the expected
+incoming jitter.
 
 =item B<--max-dtx=>I<INT>
 
@@ -820,6 +820,19 @@ or backwards (delayed) in case of a DTX buffer overflow or underflow. An
 underflow occurs when RTP packets are received slower than expected, while an
 overflow occurs when packets are received faster than expected.
 
+=item B<--dtx-cn-params=>I<INT>
+
+Specify one comfort noise parameter. This option follows the same format as
+B<cn-payload> described below.
+
+This option is applicable to audio generated to fill in transmission gaps
+during a DTX event. The default setting is no value, which means silence will
+be generated to fill in DTX gaps.
+
+If any CN parameters are configured, the parameters will be passed to an RFC
+3389 CN decoder, and the generated comfort noise will be used to fill in DTX
+gaps.
+
 =item B<--silence-detect=>I<FLOAT>
 
 Enable silence detection and specify threshold in percent. This option is
@@ -862,6 +875,10 @@ coefficients) as per RFC 3389. Allowable values for each coefficient are
 between 0 and 254. Specifying spectral information is optional and the number
 of coefficients listed (model order) is variable.
 
+This option is applicable only to B<CN> packets generated from the silence
+detection mechanism described above. The configured CN parameters are used
+directly as payload of B<CN> packets sent by B<rtpengine>.
+
 The default values are 32 (-32 dBov) for the noise level and no spectral
 information.
 

include/main.h

@@ -116,6 +116,7 @@ struct rtpengine_config {
 	int			dtx_buffer;
 	int			dtx_lag;
 	int			dtx_shift;
+	str			dtx_cn_params;
 	double			silence_detect_double;
 	uint32_t		silence_detect_int;
 	str			cn_payload;

lib/codeclib.c

@@ -697,6 +697,13 @@ int decoder_switch_dtx(decoder_t *dec, enum dtx_method dm) {
 	return 0;
 }
 
+int decoder_set_cn_dtx(decoder_t *dec, const str *cn_pl) {
+	if (decoder_switch_dtx(dec, DTX_CN))
+		return -1;
+	dec->dtx.u.cn.cn_payload = cn_pl;
+	return 0;
+}
+
 
 gboolean decoder_has_dtx(decoder_t *dec) {
 	return dec->dtx.do_dtx == NULL ? FALSE : TRUE;
@@ -2317,8 +2324,9 @@ static int cn_append_frame(decoder_t *dec, AVFrame *f, void *u1, void *u2) {
 }
 
 static int generic_cn_dtx(decoder_t *dec, GQueue *out, int ptime) {
-	static const str cn_pl = { "\x10", 1 };
-	return decoder_input_data(dec->dtx.u.cn.cn_dec, &cn_pl, dec->rtp_ts, cn_append_frame, out, NULL);
+	dec->dtx.u.cn.cn_dec->ptime = ptime;
+	return decoder_input_data(dec->dtx.u.cn.cn_dec, dec->dtx.u.cn.cn_payload,
+			dec->rtp_ts, cn_append_frame, out, NULL);
 }
 
 static int generic_cn_dtx_init(decoder_t *dec) {

lib/codeclib.h

@@ -188,6 +188,7 @@ struct dtx_method_s {
 	union {
 		struct {
 			decoder_t *cn_dec;
+			const str *cn_payload;
 		} cn;
 	} u;
 };
@@ -305,6 +306,7 @@ int decoder_input_data(decoder_t *dec, const str *data, unsigned long ts,
 		int (*callback)(decoder_t *, AVFrame *, void *u1, void *u2), void *u1, void *u2);
 gboolean decoder_has_dtx(decoder_t *);
 int decoder_switch_dtx(decoder_t *dec, enum dtx_method);
+int decoder_set_cn_dtx(decoder_t *dec, const str *);
 int decoder_dtx(decoder_t *dec, unsigned long ts, int ptime,
 		int (*callback)(decoder_t *, AVFrame *, void *u1, void *u2), void *u1, void *u2);