add delay to rtcp receiver reports (#15)

connclientread.go

@@ -94,8 +94,9 @@ func (c *ConnClient) backgroundPlayUDP(onFrameDone chan error) {
 			return
 
 		case <-reportTicker.C:
+			now := time.Now()
 			for trackId := range c.rtcpReceivers {
-				report := c.rtcpReceivers[trackId].Report()
+				report := c.rtcpReceivers[trackId].Report(now)
 				c.udpRtcpListeners[trackId].write(report)
 			}
 
@@ -161,7 +162,7 @@ func (c *ConnClient) backgroundPlayTCP(onFrameDone chan error) {
 				return
 			}
 
-			c.rtcpReceivers[frame.TrackId].OnFrame(frame.StreamType, frame.Content)
+			c.rtcpReceivers[frame.TrackId].OnFrame(time.Now(), frame.StreamType, frame.Content)
 
 			c.readCB(frame.TrackId, frame.StreamType, frame.Content)
 		}
@@ -188,8 +189,9 @@ func (c *ConnClient) backgroundPlayTCP(onFrameDone chan error) {
 			return
 
 		case <-reportTicker.C:
+			now := time.Now()
 			for trackId := range c.rtcpReceivers {
-				report := c.rtcpReceivers[trackId].Report()
+				report := c.rtcpReceivers[trackId].Report(now)
 				c.nconn.SetWriteDeadline(time.Now().Add(c.d.WriteTimeout))
 				frame := base.InterleavedFrame{
 					TrackId:    trackId,

connclientudpl.go

@@ -83,9 +83,9 @@ func (l *connClientUDPListener) run() {
 			continue
 		}
 
-		atomic.StoreInt64(l.c.udpLastFrameTimes[l.trackId], time.Now().Unix())
+		now := time.Now()
-
+		atomic.StoreInt64(l.c.udpLastFrameTimes[l.trackId], now.Unix())
-		l.c.rtcpReceivers[l.trackId].OnFrame(l.streamType, buf[:n])
+		l.c.rtcpReceivers[l.trackId].OnFrame(now, l.streamType, buf[:n])
 
 		l.c.readCB(l.trackId, l.streamType, buf[:n])
 	}

pkg/rtcpreceiver/rtcpreceiver.go

@@ -4,6 +4,7 @@ package rtcpreceiver
 import (
 	"math/rand"
 	"sync"
+	"time"
 
 	"github.com/pion/rtcp"
 
@@ -18,7 +19,8 @@ type RtcpReceiver struct {
 	senderSSRC           uint32
 	sequenceNumberCycles uint16
 	lastSequenceNumber   uint16
-	lastSenderReportTime uint32
+	lastSenderReport     uint32
+	lastSenderReportTime time.Time
 	totalLost            uint32
 	totalLostSinceRR     uint32
 	totalSinceRR         uint32
@@ -37,7 +39,7 @@ func New(receiverSSRC *uint32) *RtcpReceiver {
 }
 
 // OnFrame processes a RTP or RTCP frame and extract the needed data.
-func (rr *RtcpReceiver) OnFrame(streamType base.StreamType, buf []byte) {
+func (rr *RtcpReceiver) OnFrame(ts time.Time, streamType base.StreamType, buf []byte) {
 	rr.mutex.Lock()
 	defer rr.mutex.Unlock()
 
@@ -78,7 +80,8 @@ func (rr *RtcpReceiver) OnFrame(streamType base.StreamType, buf []byte) {
 			for _, frame := range frames {
 				if sr, ok := (frame).(*rtcp.SenderReport); ok {
 					rr.senderSSRC = sr.SSRC
-					rr.lastSenderReportTime = uint32(sr.NTPTime >> 16)
+					rr.lastSenderReport = uint32(sr.NTPTime >> 16)
+					rr.lastSenderReportTime = ts
 				}
 			}
 		}
@@ -86,7 +89,7 @@ func (rr *RtcpReceiver) OnFrame(streamType base.StreamType, buf []byte) {
 }
 
 // Report generates a RTCP receiver report.
-func (rr *RtcpReceiver) Report() []byte {
+func (rr *RtcpReceiver) Report(ts time.Time) []byte {
 	rr.mutex.Lock()
 	defer rr.mutex.Unlock()
 
@@ -96,13 +99,15 @@ func (rr *RtcpReceiver) Report() []byte {
 			{
 				SSRC:               rr.senderSSRC,
 				LastSequenceNumber: uint32(rr.sequenceNumberCycles)<<16 | uint32(rr.lastSequenceNumber),
-				LastSenderReport:   rr.lastSenderReportTime,
+				LastSenderReport:   rr.lastSenderReport,
-				FractionLost: func() uint8 {
+				// equivalent to taking the integer part after multiplying the
-					// equivalent to taking the integer part after multiplying the
+				// loss fraction by 256
-					// loss fraction by 256
+				FractionLost: uint8(float64(rr.totalLostSinceRR*256) / float64(rr.totalSinceRR)),
-					return uint8(float64(rr.totalLostSinceRR*256) / float64(rr.totalSinceRR))
+				TotalLost:    rr.totalLost,
-				}(),
+				// delay, expressed in units of 1/65536 seconds, between
-				TotalLost: rr.totalLost,
+				// receiving the last SR packet from source SSRC_n and sending this
+				// reception report block
+				Delay: uint32(ts.Sub(rr.lastSenderReportTime).Seconds() * 65536),
 			},
 		},
 	}

pkg/rtcpreceiver/rtcpreceiver_test.go

@@ -2,6 +2,7 @@ package rtcpreceiver
 
 import (
 	"testing"
+	"time"
 
 	"github.com/pion/rtcp"
 	"github.com/pion/rtp"
@@ -22,7 +23,8 @@ func TestRtcpReceiverBase(t *testing.T) {
 		OctetCount:  859127,
 	}
 	byts, _ := srPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtcp, byts)
+	ts := time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtcp, byts)
 
 	rtpPkt := rtp.Packet{
 		Header: rtp.Header{
@@ -36,7 +38,8 @@ func TestRtcpReceiverBase(t *testing.T) {
 		Payload: []byte("\x00\x00"),
 	}
 	byts, _ = rtpPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtp, byts)
+	ts = time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtp, byts)
 
 	expectedPkt := rtcp.ReceiverReport{
 		SSRC: 0x65f83afb,
@@ -45,11 +48,13 @@ func TestRtcpReceiverBase(t *testing.T) {
 				SSRC:               0xba9da416,
 				LastSequenceNumber: 946,
 				LastSenderReport:   0x887a17ce,
+				Delay:              1 * 65536,
 			},
 		},
 	}
 	expected, _ := expectedPkt.Marshal()
-	require.Equal(t, expected, rr.Report())
+	ts = time.Date(2008, 05, 20, 22, 15, 21, 0, time.UTC)
+	require.Equal(t, expected, rr.Report(ts))
 }
 
 func TestRtcpReceiverSequenceOverflow(t *testing.T) {
@@ -64,7 +69,8 @@ func TestRtcpReceiverSequenceOverflow(t *testing.T) {
 		OctetCount:  859127,
 	}
 	byts, _ := srPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtcp, byts)
+	ts := time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtcp, byts)
 
 	rtpPkt := rtp.Packet{
 		Header: rtp.Header{
@@ -78,7 +84,8 @@ func TestRtcpReceiverSequenceOverflow(t *testing.T) {
 		Payload: []byte("\x00\x00"),
 	}
 	byts, _ = rtpPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtp, byts)
+	ts = time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtp, byts)
 
 	rtpPkt = rtp.Packet{
 		Header: rtp.Header{
@@ -92,7 +99,8 @@ func TestRtcpReceiverSequenceOverflow(t *testing.T) {
 		Payload: []byte("\x00\x00"),
 	}
 	byts, _ = rtpPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtp, byts)
+	ts = time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtp, byts)
 
 	expectedPkt := rtcp.ReceiverReport{
 		SSRC: 0x65f83afb,
@@ -101,11 +109,13 @@ func TestRtcpReceiverSequenceOverflow(t *testing.T) {
 				SSRC:               0xba9da416,
 				LastSequenceNumber: 1<<16 | 0x0000,
 				LastSenderReport:   0x887a17ce,
+				Delay:              1 * 65536,
 			},
 		},
 	}
 	expected, _ := expectedPkt.Marshal()
-	require.Equal(t, expected, rr.Report())
+	ts = time.Date(2008, 05, 20, 22, 15, 21, 0, time.UTC)
+	require.Equal(t, expected, rr.Report(ts))
 }
 
 func TestRtcpReceiverPacketLost(t *testing.T) {
@@ -120,7 +130,8 @@ func TestRtcpReceiverPacketLost(t *testing.T) {
 		OctetCount:  859127,
 	}
 	byts, _ := srPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtcp, byts)
+	ts := time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtcp, byts)
 
 	rtpPkt := rtp.Packet{
 		Header: rtp.Header{
@@ -134,7 +145,8 @@ func TestRtcpReceiverPacketLost(t *testing.T) {
 		Payload: []byte("\x00\x00"),
 	}
 	byts, _ = rtpPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtp, byts)
+	ts = time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtp, byts)
 
 	rtpPkt = rtp.Packet{
 		Header: rtp.Header{
@@ -148,7 +160,8 @@ func TestRtcpReceiverPacketLost(t *testing.T) {
 		Payload: []byte("\x00\x00"),
 	}
 	byts, _ = rtpPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtp, byts)
+	ts = time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtp, byts)
 
 	expectedPkt := rtcp.ReceiverReport{
 		SSRC: 0x65f83afb,
@@ -162,11 +175,13 @@ func TestRtcpReceiverPacketLost(t *testing.T) {
 					return uint8(v * 256)
 				}(),
 				TotalLost: 1,
+				Delay:     1 * 65536,
 			},
 		},
 	}
 	expected, _ := expectedPkt.Marshal()
-	require.Equal(t, expected, rr.Report())
+	ts = time.Date(2008, 05, 20, 22, 15, 21, 0, time.UTC)
+	require.Equal(t, expected, rr.Report(ts))
 }
 
 func TestRtcpReceiverSequenceOverflowPacketLost(t *testing.T) {
@@ -181,7 +196,8 @@ func TestRtcpReceiverSequenceOverflowPacketLost(t *testing.T) {
 		OctetCount:  859127,
 	}
 	byts, _ := srPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtcp, byts)
+	ts := time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtcp, byts)
 
 	rtpPkt := rtp.Packet{
 		Header: rtp.Header{
@@ -195,7 +211,8 @@ func TestRtcpReceiverSequenceOverflowPacketLost(t *testing.T) {
 		Payload: []byte("\x00\x00"),
 	}
 	byts, _ = rtpPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtp, byts)
+	ts = time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtp, byts)
 
 	rtpPkt = rtp.Packet{
 		Header: rtp.Header{
@@ -209,7 +226,8 @@ func TestRtcpReceiverSequenceOverflowPacketLost(t *testing.T) {
 		Payload: []byte("\x00\x00"),
 	}
 	byts, _ = rtpPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtp, byts)
+	ts = time.Date(2008, 05, 20, 22, 15, 20, 0, time.UTC)
+	rr.OnFrame(ts, base.StreamTypeRtp, byts)
 
 	expectedPkt := rtcp.ReceiverReport{
 		SSRC: 0x65f83afb,
@@ -223,9 +241,11 @@ func TestRtcpReceiverSequenceOverflowPacketLost(t *testing.T) {
 					return uint8(v * 256)
 				}(),
 				TotalLost: 2,
+				Delay:     1 * 65536,
 			},
 		},
 	}
 	expected, _ := expectedPkt.Marshal()
-	require.Equal(t, expected, rr.Report())
+	ts = time.Date(2008, 05, 20, 22, 15, 21, 0, time.UTC)
+	require.Equal(t, expected, rr.Report(ts))
 }

pkg/rtcpsender/rtcpsender.go

@@ -42,12 +42,12 @@ func (rs *RtcpSender) OnFrame(ts time.Time, streamType base.StreamType, buf []by
 			if !rs.firstRtpReceived {
 				rs.firstRtpReceived = true
 				rs.senderSSRC = pkt.SSRC
-
-				// save RTP time offset and correspondent time
-				rs.rtpTimeOffset = pkt.Timestamp
-				rs.rtpTimeTime = ts
 			}
 
+			// always update time to minimize errors
+			rs.rtpTimeOffset = pkt.Timestamp
+			rs.rtpTimeTime = ts
+
 			rs.packetCount++
 			rs.octetCount += uint32(len(pkt.Payload))
 		}