Initial commit

pkg/h264/rtp.go

@@ -0,0 +1,113 @@
+package h264
+
+import (
+	"github.com/AlexxIT/go2rtc/pkg/streamer"
+	"github.com/pion/rtp"
+	"github.com/pion/rtp/codecs"
+)
+
+const RTPPacketVersionAVC = 0
+
+func RTPDepay(track *streamer.Track) streamer.WrapperFunc {
+	depack := &codecs.H264Packet{IsAVC: true}
+
+	sps, pps := GetParameterSet(track.Codec.FmtpLine)
+	sps = EncodeAVC(sps)
+	pps = EncodeAVC(pps)
+
+	var buffer []byte
+
+	return func(push streamer.WriterFunc) streamer.WriterFunc {
+		return func(packet *rtp.Packet) error {
+			//println(packet.SequenceNumber, packet.Payload[0]&0x1F, packet.Payload[0], packet.Payload[1], packet.Marker, packet.Timestamp)
+
+			data, err := depack.Unmarshal(packet.Payload)
+			if len(data) == 0 || err != nil {
+				return nil
+			}
+
+			naluType := NALUType(data)
+			//println(naluType, len(data))
+
+			switch naluType {
+			case NALUTypeSPS:
+				//println("new SPS")
+				sps = data
+				return nil
+			case NALUTypePPS:
+				//println("new PPS")
+				pps = data
+				return nil
+			}
+
+			// ffmpeg with `-tune zerolatency` enable option `-x264opts sliced-threads=1`
+			// and every NALU will be sliced to multiple NALUs
+			if !packet.Marker {
+				buffer = append(buffer, data...)
+				return nil
+			}
+
+			if buffer != nil {
+				buffer = append(buffer, data...)
+				data = buffer
+				buffer = nil
+			}
+
+			var clone rtp.Packet
+
+			if naluType == NALUTypeIFrame {
+				clone = *packet
+				clone.Version = RTPPacketVersionAVC
+				clone.Payload = sps
+				if err = push(&clone); err != nil {
+					return err
+				}
+
+				clone = *packet
+				clone.Version = RTPPacketVersionAVC
+				clone.Payload = pps
+				if err = push(&clone); err != nil {
+					return err
+				}
+			}
+
+			clone = *packet
+			clone.Version = RTPPacketVersionAVC
+			clone.Payload = data
+			return push(&clone)
+		}
+	}
+}
+
+func RTPPay(mtu uint16) streamer.WrapperFunc {
+	payloader := &Payloader{IsAVC: true}
+	sequencer := rtp.NewRandomSequencer()
+	mtu -= 12 // rtp.Header size
+
+	return func(push streamer.WriterFunc) streamer.WriterFunc {
+		return func(packet *rtp.Packet) error {
+			if packet.Version == RTPPacketVersionAVC {
+				payloads := payloader.Payload(mtu, packet.Payload)
+				for i, payload := range payloads {
+					clone := rtp.Packet{
+						Header: rtp.Header{
+							Version: 2,
+							Marker:  i == len(payloads)-1,
+							//PayloadType:    packet.PayloadType,
+							SequenceNumber: sequencer.NextSequenceNumber(),
+							Timestamp:      packet.Timestamp,
+							//SSRC:           packet.SSRC,
+						},
+						Payload: payload,
+					}
+					if err := push(&clone); err != nil {
+						return err
+					}
+				}
+				return nil
+			}
+
+			return push(packet)
+		}
+	}
+}