code clean & fix h264 test fail (#1028)

pkg/sfu/buffer/buffer.go

@@ -197,7 +197,6 @@ func (b *Buffer) Bind(params webrtc.RTPParameters, codec webrtc.RTPCodecCapabili
 		case webrtc.TypeRTCPFBNACK:
 			b.logger.Debugw("Setting feedback", "type", webrtc.TypeRTCPFBNACK)
 			b.nacker = NewNACKQueue()
-			b.nacker.SetRTT(70) // default till it is updated
 		}
 	}
 
@@ -521,15 +520,11 @@ func (b *Buffer) doReports(arrivalTime int64) {
 
 func (b *Buffer) buildNACKPacket() ([]rtcp.Packet, int) {
 	if nacks, numSeqNumsNacked := b.nacker.Pairs(); len(nacks) > 0 {
-		var pkts []rtcp.Packet
-		if len(nacks) > 0 {
-			pkts = []rtcp.Packet{&rtcp.TransportLayerNack{
-				SenderSSRC: b.mediaSSRC,
-				MediaSSRC:  b.mediaSSRC,
-				Nacks:      nacks,
-			}}
-		}
-
+		pkts := []rtcp.Packet{&rtcp.TransportLayerNack{
+			SenderSSRC: b.mediaSSRC,
+			MediaSSRC:  b.mediaSSRC,
+			Nacks:      nacks,
+		}}
 		return pkts, numSeqNumsNacked
 	}
 	return nil, 0

pkg/sfu/buffer/nack.go

@@ -24,6 +24,7 @@ type NackQueue struct {
 func NewNACKQueue() *NackQueue {
 	return &NackQueue{
 		nacks: make([]*nack, 0, cacheSize),
+		rtt:   70,
 	}
 }
 

test/client/trackwriter.go

@@ -86,7 +86,7 @@ func (w *TrackWriter) Stop() {
 func (w *TrackWriter) writeNull() {
 	defer w.onWriteComplete()
 	sample := media.Sample{Data: []byte{0x0, 0xff, 0xff, 0xff, 0xff}, Duration: 30 * time.Millisecond}
-	h264Sample := media.Sample{Data: []byte{0x5, 0xff, 0xff, 0xff, 0xff}, Duration: 30 * time.Millisecond}
+	h264Sample := media.Sample{Data: []byte{0x00, 0x00, 0x00, 0x01, 0x7, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x01, 0x8, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x01, 0x5, 0xff, 0xff, 0xff, 0xff}, Duration: 30 * time.Millisecond}
 	for {
 		select {
 		case <-time.After(20 * time.Millisecond):