add number of lost packets to rtcp receiver reports

pkg/rtcpreceiver/rtcpreceiver.go

@@ -18,6 +18,10 @@ type RtcpReceiver struct {
 	sequenceNumberCycles uint16
 	lastSequenceNumber   uint16
 	lastSenderReportTime uint32
+	totalLost            uint32
+	totalLostSinceRR     uint32
+	totalSinceRR         uint32
+	firstRtpReceived     bool
 }
 
 // New allocates a RtcpReceiver.
@@ -42,10 +46,26 @@ func (rr *RtcpReceiver) OnFrame(streamType base.StreamType, buf []byte) {
 			// extract the sequence number of the first frame
 			sequenceNumber := uint16(buf[2])<<8 | uint16(buf[3])
 
-			if sequenceNumber < rr.lastSequenceNumber {
+			if !rr.firstRtpReceived {
-				rr.sequenceNumberCycles += 1
+				rr.firstRtpReceived = true
+				rr.totalSinceRR = 1
+				rr.lastSequenceNumber = sequenceNumber
+
+			} else {
+				diff := (sequenceNumber - rr.lastSequenceNumber)
+
+				if sequenceNumber != (rr.lastSequenceNumber + 1) {
+					rr.totalLost += uint32(diff) - 1
+					rr.totalLostSinceRR += uint32(diff) - 1
+				}
+
+				if sequenceNumber < rr.lastSequenceNumber {
+					rr.sequenceNumberCycles += 1
+				}
+
+				rr.totalSinceRR += uint32(diff)
+				rr.lastSequenceNumber = sequenceNumber
 			}
-			rr.lastSequenceNumber = sequenceNumber
 		}
 
 	} else {
@@ -75,10 +95,21 @@ func (rr *RtcpReceiver) Report() []byte {
 				SSRC:               rr.senderSSRC,
 				LastSequenceNumber: uint32(rr.sequenceNumberCycles)<<16 | uint32(rr.lastSequenceNumber),
 				LastSenderReport:   rr.lastSenderReportTime,
+				FractionLost: func() uint8 {
+					f := float64(rr.totalLostSinceRR) / float64(rr.totalSinceRR)
+
+					// equivalent to taking the integer part after multiplying the
+					// loss fraction by 256
+					return uint8(f * 256)
+				}(),
+				TotalLost: rr.totalLost,
 			},
 		},
 	}
 
+	rr.totalLostSinceRR = 0
+	rr.totalSinceRR = 0
+
 	byts, _ := report.Marshal()
 	return byts
 }

pkg/rtcpreceiver/rtcpreceiver_test.go

@@ -10,10 +10,20 @@ import (
 	"github.com/aler9/gortsplib/pkg/base"
 )
 
-func TestRtcpReceiver(t *testing.T) {
+func TestRtcpReceiverBase(t *testing.T) {
 	v := uint32(0x65f83afb)
 	rr := New(&v)
 
+	srPkt := rtcp.SenderReport{
+		SSRC:        0xba9da416,
+		NTPTime:     0xe363887a17ced916,
+		RTPTime:     1287981738,
+		PacketCount: 714,
+		OctetCount:  859127,
+	}
+	byts, _ := srPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtcp, byts)
+
 	rtpPkt := rtp.Packet{
 		Header: rtp.Header{
 			Version:        2,
@@ -25,19 +35,9 @@ func TestRtcpReceiver(t *testing.T) {
 		},
 		Payload: []byte("\x00\x00"),
 	}
-	byts, _ := rtpPkt.Marshal()
+	byts, _ = rtpPkt.Marshal()
 	rr.OnFrame(base.StreamTypeRtp, byts)
 
-	srPkt := rtcp.SenderReport{
-		SSRC:        0xba9da416,
-		NTPTime:     0xe363887a17ced916,
-		RTPTime:     1287981738,
-		PacketCount: 714,
-		OctetCount:  859127,
-	}
-	byts, _ = srPkt.Marshal()
-	rr.OnFrame(base.StreamTypeRtcp, byts)
-
 	res := rr.Report()
 
 	expectedPkt := rtcp.ReceiverReport{
@@ -45,20 +45,35 @@ func TestRtcpReceiver(t *testing.T) {
 		Reports: []rtcp.ReceptionReport{
 			{
 				SSRC:               0xba9da416,
-				LastSequenceNumber: uint32(946),
+				LastSequenceNumber: 946,
-				LastSenderReport:   uint32(0x887a17ce),
+				LastSenderReport:   0x887a17ce,
 			},
 		},
 	}
 	expected, _ := expectedPkt.Marshal()
 	require.Equal(t, expected, res)
+}
 
-	rtpPkt = rtp.Packet{
+func TestRtcpReceiverSequenceOverflow(t *testing.T) {
+	v := uint32(0x65f83afb)
+	rr := New(&v)
+
+	srPkt := rtcp.SenderReport{
+		SSRC:        0xba9da416,
+		NTPTime:     0xe363887a17ced916,
+		RTPTime:     1287981738,
+		PacketCount: 714,
+		OctetCount:  859127,
+	}
+	byts, _ := srPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtcp, byts)
+
+	rtpPkt := rtp.Packet{
 		Header: rtp.Header{
 			Version:        2,
 			Marker:         true,
 			PayloadType:    96,
-			SequenceNumber: 945,
+			SequenceNumber: 0xffff,
 			Timestamp:      1287987768,
 			SSRC:           0xba9da416,
 		},
@@ -67,18 +82,158 @@ func TestRtcpReceiver(t *testing.T) {
 	byts, _ = rtpPkt.Marshal()
 	rr.OnFrame(base.StreamTypeRtp, byts)
 
-	res = rr.Report()
+	rtpPkt = rtp.Packet{
+		Header: rtp.Header{
+			Version:        2,
+			Marker:         true,
+			PayloadType:    96,
+			SequenceNumber: 0x0000,
+			Timestamp:      1287987768,
+			SSRC:           0xba9da416,
+		},
+		Payload: []byte("\x00\x00"),
+	}
+	byts, _ = rtpPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtp, byts)
 
-	expectedPkt = rtcp.ReceiverReport{
+	res := rr.Report()
+
+	expectedPkt := rtcp.ReceiverReport{
 		SSRC: 0x65f83afb,
 		Reports: []rtcp.ReceptionReport{
 			{
 				SSRC:               0xba9da416,
-				LastSequenceNumber: uint32(1<<16 | 945),
+				LastSequenceNumber: 1<<16 | 0x0000,
-				LastSenderReport:   uint32(0x887a17ce),
+				LastSenderReport:   0x887a17ce,
 			},
 		},
 	}
-	expected, _ = expectedPkt.Marshal()
+	expected, _ := expectedPkt.Marshal()
+	require.Equal(t, expected, res)
+}
+
+func TestRtcpReceiverPacketLost(t *testing.T) {
+	v := uint32(0x65f83afb)
+	rr := New(&v)
+
+	srPkt := rtcp.SenderReport{
+		SSRC:        0xba9da416,
+		NTPTime:     0xe363887a17ced916,
+		RTPTime:     1287981738,
+		PacketCount: 714,
+		OctetCount:  859127,
+	}
+	byts, _ := srPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtcp, byts)
+
+	rtpPkt := rtp.Packet{
+		Header: rtp.Header{
+			Version:        2,
+			Marker:         true,
+			PayloadType:    96,
+			SequenceNumber: 0x0120,
+			Timestamp:      1287987768,
+			SSRC:           0xba9da416,
+		},
+		Payload: []byte("\x00\x00"),
+	}
+	byts, _ = rtpPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtp, byts)
+
+	rtpPkt = rtp.Packet{
+		Header: rtp.Header{
+			Version:        2,
+			Marker:         true,
+			PayloadType:    96,
+			SequenceNumber: 0x0122,
+			Timestamp:      1287987768,
+			SSRC:           0xba9da416,
+		},
+		Payload: []byte("\x00\x00"),
+	}
+	byts, _ = rtpPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtp, byts)
+
+	res := rr.Report()
+
+	expectedPkt := rtcp.ReceiverReport{
+		SSRC: 0x65f83afb,
+		Reports: []rtcp.ReceptionReport{
+			{
+				SSRC:               0xba9da416,
+				LastSequenceNumber: 0x0122,
+				LastSenderReport:   0x887a17ce,
+				FractionLost: func() uint8 {
+					v := float64(1) / 3
+					return uint8(v * 256)
+				}(),
+				TotalLost: 1,
+			},
+		},
+	}
+	expected, _ := expectedPkt.Marshal()
+	require.Equal(t, expected, res)
+}
+
+func TestRtcpReceiverSequenceOverflowPacketLost(t *testing.T) {
+	v := uint32(0x65f83afb)
+	rr := New(&v)
+
+	srPkt := rtcp.SenderReport{
+		SSRC:        0xba9da416,
+		NTPTime:     0xe363887a17ced916,
+		RTPTime:     1287981738,
+		PacketCount: 714,
+		OctetCount:  859127,
+	}
+	byts, _ := srPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtcp, byts)
+
+	rtpPkt := rtp.Packet{
+		Header: rtp.Header{
+			Version:        2,
+			Marker:         true,
+			PayloadType:    96,
+			SequenceNumber: 0xffff,
+			Timestamp:      1287987768,
+			SSRC:           0xba9da416,
+		},
+		Payload: []byte("\x00\x00"),
+	}
+	byts, _ = rtpPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtp, byts)
+
+	rtpPkt = rtp.Packet{
+		Header: rtp.Header{
+			Version:        2,
+			Marker:         true,
+			PayloadType:    96,
+			SequenceNumber: 0x0002,
+			Timestamp:      1287987768,
+			SSRC:           0xba9da416,
+		},
+		Payload: []byte("\x00\x00"),
+	}
+	byts, _ = rtpPkt.Marshal()
+	rr.OnFrame(base.StreamTypeRtp, byts)
+
+	res := rr.Report()
+
+	expectedPkt := rtcp.ReceiverReport{
+		SSRC: 0x65f83afb,
+		Reports: []rtcp.ReceptionReport{
+			{
+				SSRC:               0xba9da416,
+				LastSequenceNumber: 1<<16 | 0x0002,
+				LastSenderReport:   0x887a17ce,
+				FractionLost: func() uint8 {
+					v := float64(2) / 4
+					return uint8(v * 256)
+				}(),
+				TotalLost: 2,
+			},
+		},
+	}
+	expected, _ := expectedPkt.Marshal()
 	require.Equal(t, expected, res)
 }