rtpsession: Don't relay more than one PLI request per RTT

Drop PLI requests if one was relay in the last RTT, the other side may
just not have received the keyframe yet.

diff --git a/gst/rtpmanager/rtpsession.c b/gst/rtpmanager/rtpsession.c
index d3a7a54..cf73043 100644 (file)
--- a/gst/rtpmanager/rtpsession.c
+++ b/gst/rtpmanager/rtpsession.c
@@ -2007,10 +2007,50 @@ rtp_session_process_app (RTPSession * sess, GstRTCPPacket * packet,
   GST_DEBUG ("received APP");
 }
 
+static void
+rtp_session_process_pli (RTPSession * sess, guint32 sender_ssrc,
+    guint32 media_ssrc, GstClockTime current_time)
+{
+  RTPSource *src;
+  guint32 round_trip = 0;
+
+  if (!sess->callbacks.request_key_unit)
+    return;
+
+  src = g_hash_table_lookup (sess->ssrcs[sess->mask_idx],
+      GINT_TO_POINTER (sender_ssrc));
+
+  if (!src)
+    return;
+
+  if (sess->last_keyframe_request != GST_CLOCK_TIME_NONE &&
+      rtp_source_get_last_rb (src, NULL, NULL, NULL, NULL, NULL, NULL,
+          &round_trip)) {
+    GstClockTime round_trip_in_ns = gst_util_uint64_scale (round_trip,
+        GST_SECOND, 65536);
+
+    if (sess->last_keyframe_request != GST_CLOCK_TIME_NONE &&
+        current_time - sess->last_keyframe_request < round_trip_in_ns) {
+      GST_DEBUG ("Ignoring PLI because one was send without one RTT (%"
+          GST_TIME_FORMAT " < %" GST_TIME_FORMAT ")",
+          GST_TIME_ARGS (current_time - sess->last_keyframe_request),
+          GST_TIME_ARGS (round_trip_in_ns));;
+      return;
+    }
+  }
+
+  sess->last_keyframe_request = current_time;
+
+  GST_LOG ("received PLI from %X %p(%p)", sender_ssrc,
+      sess->callbacks.process_rtp, sess->callbacks.request_key_unit);
+
+  sess->callbacks.request_key_unit (sess, FALSE,
+      sess->request_key_unit_user_data);
+}
 
 static void
 rtp_session_process_feedback (RTPSession * sess, GstRTCPPacket * packet,
-    RTPArrivalStats * arrival)
+    RTPArrivalStats * arrival, GstClockTime current_time)
 {
   GstRTCPType type = gst_rtcp_packet_get_type (packet);
   GstRTCPFBType fbtype = gst_rtcp_packet_fb_get_type (packet);
@@ -2052,9 +2092,8 @@ rtp_session_process_feedback (RTPSession * sess, GstRTCPPacket * packet,
       case GST_RTCP_TYPE_PSFB:
         switch (fbtype) {
           case GST_RTCP_PSFB_TYPE_PLI:
-            if (sess->callbacks.request_key_unit)
-              sess->callbacks.request_key_unit (sess, FALSE,
-                  sess->request_key_unit_user_data);
+            rtp_session_process_pli (sess, sender_ssrc, media_ssrc,
+                current_time);
             break;
           default:
             break;
@@ -2136,7 +2175,7 @@ rtp_session_process_rtcp (RTPSession * sess, GstBuffer * buffer,
         break;
       case GST_RTCP_TYPE_RTPFB:
       case GST_RTCP_TYPE_PSFB:
-        rtp_session_process_feedback (sess, &packet, &arrival);
+        rtp_session_process_feedback (sess, &packet, &arrival, current_time);
         break;
       default:
         GST_WARNING ("got unknown RTCP packet");

diff --git a/gst/rtpmanager/rtpsession.h b/gst/rtpmanager/rtpsession.h
index 0cc1f6b..9510942 100644 (file)
--- a/gst/rtpmanager/rtpsession.h
+++ b/gst/rtpmanager/rtpsession.h
@@ -221,6 +221,7 @@ struct _RTPSession {
   GstClockTime  rtcp_feedback_retention_window;
 
   GArray       *rtcp_pli_requests;
+  GstClockTime last_keyframe_request;
 };
 
 /**