Silicon Graphics Movie demuxer

[ffmpeg] / libavformat / rtpenc.c

diff --git a/libavformat/rtpenc.c b/libavformat/rtpenc.c
index babb2bb45f2aca56365a3444323acb43dcedc14e..83167eba9c3aef04a17cd244eba9f201e97bd327 100644 (file)
--- a/libavformat/rtpenc.c
+++ b/libavformat/rtpenc.c
@@ -28,12 +28,12 @@
 
 #include "rtpenc.h"
 
-//#define DEBUG
-
 static const AVOption options[] = {
     FF_RTP_FLAG_OPTS(RTPMuxContext, flags),
     { "payload_type", "Specify RTP payload type", offsetof(RTPMuxContext, payload_type), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, 127, AV_OPT_FLAG_ENCODING_PARAM },
     { "ssrc", "Stream identifier", offsetof(RTPMuxContext, ssrc), AV_OPT_TYPE_INT, { .i64 = 0 }, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },
+    { "cname", "CNAME to include in RTCP SR packets", offsetof(RTPMuxContext, cname), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
+    { "seq", "Starting sequence number", offsetof(RTPMuxContext, seq), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, 65535, AV_OPT_FLAG_ENCODING_PARAM },
     { NULL },
 };
 
@@ -123,6 +123,13 @@ static int rtp_write_header(AVFormatContext *s1)
         /* Round the NTP time to whole milliseconds. */
         s->first_rtcp_ntp_time = (s1->start_time_realtime / 1000) * 1000 +
                                  NTP_OFFSET_US;
+    // Pick a random sequence start number, but in the lower end of the
+    // available range, so that any wraparound doesn't happen immediately.
+    // (Immediate wraparound would be an issue for SRTP.)
+    if (s->seq < 0)
+        s->seq = av_get_random_seed() & 0x0fff;
+    else
+        s->seq &= 0xffff; // Use the given parameter, wrapped to the right interval
 
     if (s1->packet_size) {
         if (s1->pb->max_packet_size)
@@ -252,7 +259,7 @@ fail:
 }
 
 /* send an rtcp sender report packet */
-static void rtcp_send_sr(AVFormatContext *s1, int64_t ntp_time)
+static void rtcp_send_sr(AVFormatContext *s1, int64_t ntp_time, int bye)
 {
     RTPMuxContext *s = s1->priv_data;
     uint32_t rtp_ts;
@@ -262,15 +269,37 @@ static void rtcp_send_sr(AVFormatContext *s1, int64_t ntp_time)
     s->last_rtcp_ntp_time = ntp_time;
     rtp_ts = av_rescale_q(ntp_time - s->first_rtcp_ntp_time, (AVRational){1, 1000000},
                           s1->streams[0]->time_base) + s->base_timestamp;
-    avio_w8(s1->pb, (RTP_VERSION << 6));
+    avio_w8(s1->pb, RTP_VERSION << 6);
     avio_w8(s1->pb, RTCP_SR);
     avio_wb16(s1->pb, 6); /* length in words - 1 */
     avio_wb32(s1->pb, s->ssrc);
-    avio_wb32(s1->pb, ntp_time / 1000000);
-    avio_wb32(s1->pb, ((ntp_time % 1000000) << 32) / 1000000);
+    avio_wb64(s1->pb, NTP_TO_RTP_FORMAT(ntp_time));
     avio_wb32(s1->pb, rtp_ts);
     avio_wb32(s1->pb, s->packet_count);
     avio_wb32(s1->pb, s->octet_count);
+
+    if (s->cname) {
+        int len = FFMIN(strlen(s->cname), 255);
+        avio_w8(s1->pb, (RTP_VERSION << 6) + 1);
+        avio_w8(s1->pb, RTCP_SDES);
+        avio_wb16(s1->pb, (7 + len + 3) / 4); /* length in words - 1 */
+
+        avio_wb32(s1->pb, s->ssrc);
+        avio_w8(s1->pb, 0x01); /* CNAME */
+        avio_w8(s1->pb, len);
+        avio_write(s1->pb, s->cname, len);
+        avio_w8(s1->pb, 0); /* END */
+        for (len = (7 + len) % 4; len % 4; len++)
+            avio_w8(s1->pb, 0);
+    }
+
+    if (bye) {
+        avio_w8(s1->pb, (RTP_VERSION << 6) | 1);
+        avio_w8(s1->pb, RTCP_BYE);
+        avio_wb16(s1->pb, 1); /* length in words - 1 */
+        avio_wb32(s1->pb, s->ssrc);
+    }
+
     avio_flush(s1->pb);
 }
 
@@ -283,7 +312,7 @@ void ff_rtp_send_data(AVFormatContext *s1, const uint8_t *buf1, int len, int m)
     av_dlog(s1, "rtp_send_data size=%d\n", len);
 
     /* build the RTP header */
-    avio_w8(s1->pb, (RTP_VERSION << 6));
+    avio_w8(s1->pb, RTP_VERSION << 6);
     avio_w8(s1->pb, (s->payload_type & 0x7f) | ((m & 0x01) << 7));
     avio_wb16(s1->pb, s->seq);
     avio_wb32(s1->pb, s->timestamp);
@@ -292,7 +321,7 @@ void ff_rtp_send_data(AVFormatContext *s1, const uint8_t *buf1, int len, int m)
     avio_write(s1->pb, buf1, len);
     avio_flush(s1->pb);
 
-    s->seq++;
+    s->seq = (s->seq + 1) & 0xffff;
     s->octet_count += len;
     s->packet_count++;
 }
@@ -469,7 +498,7 @@ static int rtp_write_packet(AVFormatContext *s1, AVPacket *pkt)
     if ((s->first_packet || ((rtcp_bytes >= RTCP_SR_SIZE) &&
                             (ff_ntp_time() - s->last_rtcp_ntp_time > 5000000))) &&
         !(s->flags & FF_RTP_FLAG_SKIP_RTCP)) {
-        rtcp_send_sr(s1, ff_ntp_time());
+        rtcp_send_sr(s1, ff_ntp_time(), 0);
         s->last_octet_count = s->octet_count;
         s->first_packet = 0;
     }
@@ -565,6 +594,10 @@ static int rtp_write_trailer(AVFormatContext *s1)
 {
     RTPMuxContext *s = s1->priv_data;
 
+    /* If the caller closes and recreates ->pb, this might actually
+     * be NULL here even if it was successfully allocated at the start. */
+    if (s1->pb && (s->flags & FF_RTP_FLAG_SEND_BYE))
+        rtcp_send_sr(s1, ff_ntp_time(), 1);
     av_freep(&s->buf);
 
     return 0;