Restore fix for Chinese buggy cameras

pkg/h264/annexb/annexb.go

@@ -139,3 +139,22 @@ func IndexFrame(b []byte) int {
 
 	return -1
 }
+
+func FixAnnexBInAVCC(b []byte) []byte {
+	for i := 0; i < len(b); {
+		if i+4 >= len(b) {
+			break
+		}
+
+		size := bytes.Index(b[i+4:], []byte{0, 0, 0, 1})
+		if size < 0 {
+			size = len(b) - (i + 4)
+		}
+
+		binary.BigEndian.PutUint32(b[i:], uint32(size))
+
+		i += size + 4
+	}
+
+	return b
+}

pkg/h264/rtp.go

@@ -83,10 +83,10 @@ func RTPDepay(codec *core.Codec, handler core.HandlerFunc) core.HandlerFunc {
 			// some Chinese buggy cameras has single packet with SPS+PPS+IFrame separated by 00 00 00 01
 			// https://github.com/AlexxIT/WebRTC/issues/391
 			// https://github.com/AlexxIT/WebRTC/issues/392
-			payload = annexb.EncodeToAVCC(payload, false)
+			payload = annexb.FixAnnexBInAVCC(payload)
 		}
 
-		//log.Printf("[AVC] %v, len: %d, ts: %10d, seq: %d", Types(payload), len(payload), packet.Timestamp, packet.SequenceNumber)
+		//log.Printf("[AVC] %v, len: %d, ts: %10d, seq: %d", NALUTypes(payload), len(payload), packet.Timestamp, packet.SequenceNumber)
 
 		clone := *packet
 		clone.Version = RTPPacketVersionAVC