Merge pull request #33 from freddy36/rtp-out

RTP output support

README

@@ -40,6 +40,9 @@ This is useful for hardware modulators that require correct PCR values
 (most cheap modulators do, so always use "-m 3" with them).
 mptsd was tested and found to be working ok with Dektec DTE-3114 & HiDes UT-100C.
 
+To enable RTP output instead of plain UDP for network streams,
+specify the SSRC identifier via the -s flag (must be != 0).
+
 Development
 ===========
 The development is tracked using git. The repository is hosted at github

config.c

@@ -431,6 +431,7 @@ static void show_usage(void) {
 	puts("\t-P ip\t\tOutput udp port             (default: 5000)");
 	puts("\t-o ip\t\tOutput interface address    (default: 0.0.0.0)");
 	puts("\t-t ttl\t\tSet multicast ttl           (default: 1)");
+	puts("\t-s SSRC\t\tEnables RTP                 (default: disabled)");
 	puts("");
 	puts("\t-B Mbps\t\tOutput bitrate in Mbps      (default: 38.00)");
 	puts("\t-m mode\t\tPCR mode (modes list bellow)");
@@ -453,13 +454,15 @@ void config_load(CONFIG *conf, int argc, char **argv) {
 
 	conf->multicast_ttl = 1;
 	conf->output->out_port = 5000;
+	conf->output->rtp_sequence_number = 1;
+	conf->output->rtp_ssrc = 0;
 	conf->output_bitrate = 38;
 	conf->logport = 514;
 	conf->server_port = 0;
 	conf->server_socket = -1;
 	conf->write_output_network = 1;
 
-	while ((j = getopt(argc, argv, "i:b:p:g:c:n:e:d:t:o:O:P:l:L:B:m:qDHhEWN")) != -1) {
+	while ((j = getopt(argc, argv, "i:b:p:g:c:n:e:d:t:o:O:P:l:L:B:m:s:qDHhEWN")) != -1) {
 		switch (j) {
 			case 'i':
 				conf->ident = strdup(optarg);
@@ -511,6 +514,9 @@ void config_load(CONFIG *conf, int argc, char **argv) {
 					exit(1);
 				}
 				break;
+			case 's':
+				conf->output->rtp_ssrc = strtoul(optarg, NULL, 10);
+				break;
 			case 'm':
 				conf->pcr_mode = atoi(optarg);
 				if (conf->pcr_mode < 0 || conf->pcr_mode > 4)
@@ -595,10 +601,11 @@ void config_load(CONFIG *conf, int argc, char **argv) {
 		printf("\tGlobal config     : %s\n", conf->global_conf);
 		printf("\tChannels config   : %s\n", conf->channels_conf);
 		printf("\tNIT config        : %s\n", conf->nit_conf);
-		printf("\tOutput addr       : udp://%s:%d\n", inet_ntoa(conf->output->out_host), conf->output->out_port);
+		printf("\tOutput addr       : %s://%s:%d\n", (conf->output->rtp_ssrc != 0 ? "rtp" : "udp"), inet_ntoa(conf->output->out_host), conf->output->out_port);
 		if (conf->output_intf.s_addr)
 			printf("\tOutput iface addr : %s\n", inet_ntoa(conf->output_intf));
 		printf("\tMulticast ttl     : %d\n", conf->multicast_ttl);
+		printf("\tRTP SSRC          : %u\n", conf->output->rtp_ssrc);
 		if (conf->syslog_active) {
 			printf("\tSyslog host       : %s\n", conf->loghost);
 			printf("\tSyslog port       : %d\n", conf->logport);

data.h

@@ -210,6 +210,9 @@ typedef struct {
 	uint64_t last_org_pcr[8193];	// Last PCR value indexed by PID x
 	uint64_t last_pcr[8193];		// Last PCR value indexed by PID x
 	uint64_t last_traffic[8193];	// Last traffic when PCR with PID x was seen
+
+	uint16_t rtp_sequence_number;	// RTP sequence number
+	uint32_t rtp_ssrc;				// use RTP is != 0
 } OUTPUT;
 
 typedef struct {

output_write.c

@@ -100,6 +100,8 @@ void ts_frame_process(CONFIG *conf, OUTPUT *o, uint8_t *data) {
 	}
 }
 
+
+// write plain UDP packets
 ssize_t ts_frame_write(OUTPUT *o, uint8_t *data) {
 	ssize_t written;
 	written = fdwrite(o->out_sock, (char *)data, FRAME_PACKET_SIZE);
@@ -114,6 +116,55 @@ ssize_t ts_frame_write(OUTPUT *o, uint8_t *data) {
 	return written;
 }
 
+
+// write RTP packets
+ssize_t ts_frame_write_rtp(OUTPUT *o, uint8_t *data) {
+	ssize_t written;
+	const size_t write_len = FRAME_PACKET_SIZE + RTP_HEADER_SIZE;
+	uint8_t rtp_buffer[write_len];
+
+	rtp_buffer[0] = (((2 & 0x03) << 6)			// version
+					 | ((0 & 0x01) << 5)		// padding
+					 | ((0 & 0x01) << 4)		// extension
+					 | ((0 & 0x0F) << 0));		// cc
+
+	rtp_buffer[1] = ( ((0  & 0x01) << 7)		// Marker
+	 				| ((33 & 0x7F) << 0) );		// Payload type: MPEG-II transport streams (33)
+
+	// sequence number
+	uint16_t seq = htons(o->rtp_sequence_number);
+	memcpy (&rtp_buffer[2], &seq, 2);
+
+	// timestamp
+	struct timespec ts;
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	uint64_t time = ts.tv_sec * 1000000ll + ts.tv_nsec / 1000;
+	uint32_t timestamp_value = (uint32_t) (90000 * (time/1000000ll))+(9*(time%1000000ll))/100; // 90 kHz Clock
+	uint32_t timestamp = htonl(timestamp_value);
+	memcpy (&rtp_buffer[4], &timestamp, 4);
+
+	// SSRC
+	uint32_t ssrc = htonl(o->rtp_ssrc);
+	memcpy (&rtp_buffer[8], &ssrc, 4);
+
+	// copy payload
+	memcpy(&rtp_buffer[12], data, FRAME_PACKET_SIZE);
+
+	written = fdwrite(o->out_sock, (char *)rtp_buffer, write_len);
+	if (written >= RTP_HEADER_SIZE) {
+		written -= RTP_HEADER_SIZE;
+		o->traffic        += written;
+		o->traffic_period += written;
+	}
+
+	if (o->ofd)
+		write(o->ofd, data, FRAME_PACKET_SIZE);
+
+	o->rtp_sequence_number++; // increment RTP sequence number
+
+	return written;
+}
+
 void * output_handle_write(void *_config) {
 	CONFIG *conf = _config;
 	OUTPUT *o = conf->output;
@@ -169,7 +220,11 @@ void * output_handle_write(void *_config) {
 			long sleep_interval = conf->output_tmout;
 			uint8_t *ts_frame = curbuf->buf + curbuf->written;
 			ts_frame_process(conf, o, ts_frame);	// Fix PCR and count NULL packets
-			written += ts_frame_write(o, ts_frame);	// Write packet to network/file
+			if (o->rtp_ssrc != 0) {
+				written += ts_frame_write_rtp(o, ts_frame); // Write RTP packet to network/file
+			} else {
+				written += ts_frame_write(o, ts_frame);	// Write plain UDP packet to network/file
+			}
 			curbuf->written += FRAME_PACKET_SIZE;
 			if (packets_written) {
 				time_taken = timeval_diff_usec(&start_write_ts, &used_ts);