move RTP packet handling into separate package

client.go

@@ -24,13 +24,12 @@ import (
 
 	"github.com/aler9/gortsplib/pkg/auth"
 	"github.com/aler9/gortsplib/pkg/base"
-	"github.com/aler9/gortsplib/pkg/h264"
 	"github.com/aler9/gortsplib/pkg/headers"
 	"github.com/aler9/gortsplib/pkg/liberrors"
 	"github.com/aler9/gortsplib/pkg/ringbuffer"
 	"github.com/aler9/gortsplib/pkg/rtcpreceiver"
 	"github.com/aler9/gortsplib/pkg/rtcpsender"
-	"github.com/aler9/gortsplib/pkg/rtph264"
+	"github.com/aler9/gortsplib/pkg/rtpproc"
 	"github.com/aler9/gortsplib/pkg/sdp"
 	"github.com/aler9/gortsplib/pkg/url"
 )
@@ -91,8 +90,7 @@ type clientTrack struct {
 	tcpChannel      int
 	rtcpReceiver    *rtcpreceiver.RTCPReceiver
 	rtcpSender      *rtcpsender.RTCPSender
-	h264Decoder     *rtph264.Decoder
-	h264Encoder     *rtph264.Encoder
+	proc            *rtpproc.Processor
 }
 
 func (s clientState) String() string {
@@ -710,10 +708,8 @@ func (c *Client) playRecordStart() {
 
 	if c.state == clientStatePlay {
 		for _, ct := range c.tracks {
-			if _, ok := ct.track.(*TrackH264); ok {
-				ct.h264Decoder = &rtph264.Decoder{}
-				ct.h264Decoder.Init()
-			}
+			_, isH264 := ct.track.(*TrackH264)
+			ct.proc = rtpproc.NewProcessor(isH264, *c.effectiveTransport == TransportTCP)
 		}
 
 		c.keepaliveTimer = time.NewTimer(c.keepalivePeriod)
@@ -812,57 +808,19 @@ func (c *Client) runReader() {
 							return err
 						}
 
-						ctx := ClientOnPacketRTPCtx{
-							TrackID: trackID,
-							Packet:  pkt,
+						out, err := c.tracks[trackID].proc.Process(pkt)
+						if err != nil {
+							return err
 						}
-						ct := c.tracks[trackID]
-						c.processPacketRTP(ct, &ctx)
 
-						if ct.h264Decoder != nil {
-							if ct.h264Encoder == nil && len(payload) > maxPacketSize {
-								v1 := pkt.SSRC
-								v2 := pkt.SequenceNumber
-								v3 := pkt.Timestamp
-								ct.h264Encoder = &rtph264.Encoder{
-									PayloadType:           pkt.PayloadType,
-									SSRC:                  &v1,
-									InitialSequenceNumber: &v2,
-									InitialTimestamp:      &v3,
-								}
-								ct.h264Encoder.Init()
-							}
-
-							if ct.h264Encoder != nil {
-								if ctx.H264NALUs != nil {
-									packets, err := ct.h264Encoder.Encode(ctx.H264NALUs, ctx.H264PTS)
-									if err != nil {
-										return err
-									}
-
-									for i, pkt := range packets {
-										if i != len(packets)-1 {
-											c.OnPacketRTP(&ClientOnPacketRTPCtx{
-												TrackID:      trackID,
-												Packet:       pkt,
-												PTSEqualsDTS: false,
-											})
-										} else {
-											ctx.Packet = pkt
-											c.OnPacketRTP(&ctx)
-										}
-									}
-								}
-							} else {
-								c.OnPacketRTP(&ctx)
-							}
-						} else {
-							if len(payload) > maxPacketSize {
-								return fmt.Errorf("payload size (%d) greater than maximum allowed (%d)",
-									len(payload), maxPacketSize)
-							}
-
-							c.OnPacketRTP(&ctx)
+						for _, entry := range out {
+							c.OnPacketRTP(&ClientOnPacketRTPCtx{
+								TrackID:      trackID,
+								Packet:       entry.Packet,
+								PTSEqualsDTS: entry.PTSEqualsDTS,
+								H264NALUs:    entry.H264NALUs,
+								H264PTS:      entry.H264PTS,
+							})
 						}
 					} else {
 						if len(payload) > maxPacketSize {
@@ -975,8 +933,7 @@ func (c *Client) playRecordStop(isClosing bool) {
 	}
 
 	for _, ct := range c.tracks {
-		ct.h264Decoder = nil
-		ct.h264Encoder = nil
+		ct.proc = nil
 	}
 
 	// stop timers
@@ -1928,24 +1885,6 @@ func (c *Client) runWriter() {
 	}
 }
 
-func (c *Client) processPacketRTP(ct *clientTrack, ctx *ClientOnPacketRTPCtx) {
-	// remove padding
-	ctx.Packet.Header.Padding = false
-	ctx.Packet.PaddingSize = 0
-
-	// decode
-	if ct.h264Decoder != nil {
-		nalus, pts, err := ct.h264Decoder.DecodeUntilMarker(ctx.Packet)
-		if err == nil {
-			ctx.PTSEqualsDTS = h264.IDRPresent(nalus)
-			ctx.H264NALUs = nalus
-			ctx.H264PTS = pts
-		}
-	} else {
-		ctx.PTSEqualsDTS = true
-	}
-}
-
 // WritePacketRTP writes a RTP packet.
 func (c *Client) WritePacketRTP(trackID int, pkt *rtp.Packet, ptsEqualsDTS bool) error {
 	c.writeMutex.RLock()

client_read_test.go

@@ -220,7 +220,7 @@ func TestClientRead(t *testing.T) {
 				require.Equal(t, base.Describe, req.Method)
 				require.Equal(t, mustParseURL(scheme+"://"+listenIP+":8554/test/stream?param=value"), req.URL)
 
-				track, err := NewTrackH264(96, []byte{0x01, 0x02, 0x03, 0x04}, []byte{0x01, 0x02, 0x03, 0x04}, nil)
+				track, err := NewTrackGeneric("application", []string{"97"}, "97 private/90000", "")
 				require.NoError(t, err)
 
 				tracks := Tracks{track}

clientudpl.go

@@ -178,14 +178,23 @@ func (u *clientUDPListener) processPlayRTP(now time.Time, payload []byte) {
 		return
 	}
 
-	ctx := ClientOnPacketRTPCtx{
-		TrackID: u.trackID,
-		Packet:  pkt,
-	}
 	ct := u.c.tracks[u.trackID]
-	u.c.processPacketRTP(ct, &ctx)
-	ct.rtcpReceiver.ProcessPacketRTP(time.Now(), pkt, ctx.PTSEqualsDTS)
-	u.c.OnPacketRTP(&ctx)
+
+	out, err := ct.proc.Process(pkt)
+	if err != nil {
+		return
+	}
+	out0 := out[0]
+
+	ct.rtcpReceiver.ProcessPacketRTP(time.Now(), pkt, out0.PTSEqualsDTS)
+
+	u.c.OnPacketRTP(&ClientOnPacketRTPCtx{
+		TrackID:      u.trackID,
+		Packet:       out0.Packet,
+		PTSEqualsDTS: out0.PTSEqualsDTS,
+		H264NALUs:    out0.H264NALUs,
+		H264PTS:      out0.H264PTS,
+	})
 }
 
 func (u *clientUDPListener) processPlayRTCP(now time.Time, payload []byte) {

pkg/rtpproc/processor.go

@@ -0,0 +1,134 @@
+package rtpproc
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/pion/rtp"
+
+	"github.com/aler9/gortsplib/pkg/h264"
+	"github.com/aler9/gortsplib/pkg/rtph264"
+)
+
+const (
+	// 1500 (UDP MTU) - 20 (IP header) - 8 (UDP header)
+	maxPacketSize = 1472
+)
+
+// ProcessorOutput is the output of Process().
+type ProcessorOutput struct {
+	Packet       *rtp.Packet
+	PTSEqualsDTS bool
+	H264NALUs    [][]byte
+	H264PTS      time.Duration
+}
+
+// Processor is used to process incoming RTP packets, in order to:
+// - remove padding
+// - decode packets encoded with supported codecs
+// - re-encode packets if they are bigger than maximum allowed.
+type Processor struct {
+	isH264 bool
+	isTCP  bool
+
+	h264Decoder *rtph264.Decoder
+	h264Encoder *rtph264.Encoder
+}
+
+// NewProcessor allocates a Processor.
+func NewProcessor(isH264 bool, isTCP bool) *Processor {
+	p := &Processor{
+		isH264: isH264,
+		isTCP:  isTCP,
+	}
+
+	if isH264 {
+		p.h264Decoder = &rtph264.Decoder{}
+		p.h264Decoder.Init()
+	}
+
+	return p
+}
+
+func (p *Processor) processH264(pkt *rtp.Packet) ([]*ProcessorOutput, error) {
+	// decode
+	nalus, pts, err := p.h264Decoder.DecodeUntilMarker(pkt)
+	if err != nil {
+		if err == rtph264.ErrNonStartingPacketAndNoPrevious ||
+			err == rtph264.ErrMorePacketsNeeded {
+			return []*ProcessorOutput{{
+				Packet:       pkt,
+				PTSEqualsDTS: false,
+			}}, nil
+		}
+		return nil, err
+	}
+	ptsEqualsDTS := h264.IDRPresent(nalus)
+
+	// re-encode if packets use non-standard sizes
+	if p.isTCP && p.h264Encoder == nil && pkt.MarshalSize() > maxPacketSize {
+		v1 := pkt.SSRC
+		v2 := pkt.SequenceNumber
+		v3 := pkt.Timestamp
+		p.h264Encoder = &rtph264.Encoder{
+			PayloadType:           pkt.PayloadType,
+			SSRC:                  &v1,
+			InitialSequenceNumber: &v2,
+			InitialTimestamp:      &v3,
+		}
+		p.h264Encoder.Init()
+	}
+
+	if p.h264Encoder != nil {
+		packets, err := p.h264Encoder.Encode(nalus, pts)
+		if err != nil {
+			return nil, err
+		}
+
+		output := make([]*ProcessorOutput, len(packets))
+
+		for i, pkt := range packets {
+			if i != len(packets)-1 {
+				output[i] = &ProcessorOutput{
+					Packet:       pkt,
+					PTSEqualsDTS: false,
+				}
+			} else {
+				output[i] = &ProcessorOutput{
+					Packet:       pkt,
+					PTSEqualsDTS: ptsEqualsDTS,
+				}
+			}
+		}
+
+		return output, nil
+	}
+
+	return []*ProcessorOutput{{
+		Packet:       pkt,
+		PTSEqualsDTS: ptsEqualsDTS,
+		H264NALUs:    nalus,
+		H264PTS:      pts,
+	}}, nil
+}
+
+// Process processes a RTP packet.
+func (p *Processor) Process(pkt *rtp.Packet) ([]*ProcessorOutput, error) {
+	// remove padding
+	pkt.Header.Padding = false
+	pkt.PaddingSize = 0
+
+	if p.h264Decoder != nil {
+		return p.processH264(pkt)
+	}
+
+	if p.isTCP && pkt.MarshalSize() > maxPacketSize {
+		return nil, fmt.Errorf("payload size (%d) greater than maximum allowed (%d)",
+			pkt.MarshalSize(), maxPacketSize)
+	}
+
+	return []*ProcessorOutput{{
+		Packet:       pkt,
+		PTSEqualsDTS: true,
+	}}, nil
+}

serverconn.go

@@ -15,7 +15,6 @@ import (
 
 	"github.com/aler9/gortsplib/pkg/base"
 	"github.com/aler9/gortsplib/pkg/liberrors"
-	"github.com/aler9/gortsplib/pkg/rtph264"
 	"github.com/aler9/gortsplib/pkg/url"
 )
 
@@ -258,66 +257,21 @@ func (sc *ServerConn) readFuncTCP(readRequest chan readReq) error {
 					return err
 				}
 
-				ctx := ServerHandlerOnPacketRTPCtx{
-					Session: sc.session,
-					TrackID: trackID,
-					Packet:  pkt,
+				out, err := sc.session.announcedTracks[trackID].proc.Process(pkt)
+				if err != nil {
+					return err
 				}
-				at := sc.session.announcedTracks[trackID]
-				sc.session.processPacketRTP(at, &ctx)
 
-				if at.h264Decoder != nil {
-					if at.h264Encoder == nil && len(payload) > maxPacketSize {
-						v1 := pkt.SSRC
-						v2 := pkt.SequenceNumber
-						v3 := pkt.Timestamp
-						at.h264Encoder = &rtph264.Encoder{
-							PayloadType:           pkt.PayloadType,
-							SSRC:                  &v1,
-							InitialSequenceNumber: &v2,
-							InitialTimestamp:      &v3,
-						}
-						at.h264Encoder.Init()
-					}
-
-					if at.h264Encoder != nil {
-						if ctx.H264NALUs != nil {
-							packets, err := at.h264Encoder.Encode(ctx.H264NALUs, ctx.H264PTS)
-							if err != nil {
-								return err
-							}
-
-							for i, pkt := range packets {
-								if i != len(packets)-1 {
-									if h, ok := sc.s.Handler.(ServerHandlerOnPacketRTP); ok {
-										h.OnPacketRTP(&ServerHandlerOnPacketRTPCtx{
-											Session:      sc.session,
-											TrackID:      trackID,
-											Packet:       pkt,
-											PTSEqualsDTS: false,
-										})
-									}
-								} else {
-									ctx.Packet = pkt
-									if h, ok := sc.s.Handler.(ServerHandlerOnPacketRTP); ok {
-										h.OnPacketRTP(&ctx)
-									}
-								}
-							}
-						}
-					} else {
-						if h, ok := sc.s.Handler.(ServerHandlerOnPacketRTP); ok {
-							h.OnPacketRTP(&ctx)
-						}
-					}
-				} else {
-					if len(payload) > maxPacketSize {
-						return fmt.Errorf("payload size (%d) greater than maximum allowed (%d)",
-							len(payload), maxPacketSize)
-					}
-
-					if h, ok := sc.s.Handler.(ServerHandlerOnPacketRTP); ok {
-						h.OnPacketRTP(&ctx)
+				if h, ok := sc.s.Handler.(ServerHandlerOnPacketRTP); ok {
+					for _, entry := range out {
+						h.OnPacketRTP(&ServerHandlerOnPacketRTPCtx{
+							Session:      sc.session,
+							TrackID:      trackID,
+							Packet:       entry.Packet,
+							PTSEqualsDTS: entry.PTSEqualsDTS,
+							H264NALUs:    entry.H264NALUs,
+							H264PTS:      entry.H264PTS,
+						})
 					}
 				}
 			} else {

serversession.go

@@ -14,12 +14,11 @@ import (
 	"github.com/pion/rtp"
 
 	"github.com/aler9/gortsplib/pkg/base"
-	"github.com/aler9/gortsplib/pkg/h264"
 	"github.com/aler9/gortsplib/pkg/headers"
 	"github.com/aler9/gortsplib/pkg/liberrors"
 	"github.com/aler9/gortsplib/pkg/ringbuffer"
 	"github.com/aler9/gortsplib/pkg/rtcpreceiver"
-	"github.com/aler9/gortsplib/pkg/rtph264"
+	"github.com/aler9/gortsplib/pkg/rtpproc"
 	"github.com/aler9/gortsplib/pkg/url"
 )
 
@@ -154,8 +153,7 @@ type ServerSessionSetuppedTrack struct {
 type ServerSessionAnnouncedTrack struct {
 	track        Track
 	rtcpReceiver *rtcpreceiver.RTCPReceiver
-	h264Decoder  *rtph264.Decoder
-	h264Encoder  *rtph264.Encoder
+	proc         *rtpproc.Processor
 }
 
 // ServerSession is a server-side RTSP session.
@@ -980,10 +978,8 @@ func (ss *ServerSession) handleRequest(sc *ServerConn, req *base.Request) (*base
 		ss.state = ServerSessionStateRecord
 
 		for _, at := range ss.announcedTracks {
-			if _, ok := at.track.(*TrackH264); ok {
-				at.h264Decoder = &rtph264.Decoder{}
-				at.h264Decoder.Init()
-			}
+			_, isH264 := at.track.(*TrackH264)
+			at.proc = rtpproc.NewProcessor(isH264, *ss.setuppedTransport == TransportTCP)
 		}
 
 		switch *ss.setuppedTransport {
@@ -1104,8 +1100,7 @@ func (ss *ServerSession) handleRequest(sc *ServerConn, req *base.Request) (*base
 			}
 
 			for _, at := range ss.announcedTracks {
-				at.h264Decoder = nil
-				at.h264Encoder = nil
+				at.proc = nil
 			}
 
 			ss.state = ServerSessionStatePreRecord
@@ -1215,24 +1210,6 @@ func (ss *ServerSession) runWriter() {
 	}
 }
 
-func (ss *ServerSession) processPacketRTP(at *ServerSessionAnnouncedTrack, ctx *ServerHandlerOnPacketRTPCtx) {
-	// remove padding
-	ctx.Packet.Header.Padding = false
-	ctx.Packet.PaddingSize = 0
-
-	// decode
-	if at.h264Decoder != nil {
-		nalus, pts, err := at.h264Decoder.DecodeUntilMarker(ctx.Packet)
-		if err == nil {
-			ctx.PTSEqualsDTS = h264.IDRPresent(nalus)
-			ctx.H264NALUs = nalus
-			ctx.H264PTS = pts
-		}
-	} else {
-		ctx.PTSEqualsDTS = true
-	}
-}
-
 func (ss *ServerSession) onPacketRTCP(trackID int, pkt rtcp.Packet) {
 	if h, ok := ss.s.Handler.(ServerHandlerOnPacketRTCP); ok {
 		h.OnPacketRTCP(&ServerHandlerOnPacketRTCPCtx{

serverudpl.go

@@ -203,17 +203,25 @@ func (u *serverUDPListener) processRTP(clientData *clientData, payload []byte) {
 	now := time.Now()
 	atomic.StoreInt64(clientData.ss.udpLastFrameTime, now.Unix())
 
-	ctx := ServerHandlerOnPacketRTPCtx{
-		Session: clientData.ss,
-		TrackID: clientData.trackID,
-		Packet:  pkt,
-	}
 	at := clientData.ss.announcedTracks[clientData.trackID]
-	clientData.ss.processPacketRTP(at, &ctx)
 
-	at.rtcpReceiver.ProcessPacketRTP(now, ctx.Packet, ctx.PTSEqualsDTS)
+	out, err := at.proc.Process(pkt)
+	if err != nil {
+		return
+	}
+	out0 := out[0]
+
+	at.rtcpReceiver.ProcessPacketRTP(now, pkt, out0.PTSEqualsDTS)
+
 	if h, ok := clientData.ss.s.Handler.(ServerHandlerOnPacketRTP); ok {
-		h.OnPacketRTP(&ctx)
+		h.OnPacketRTP(&ServerHandlerOnPacketRTPCtx{
+			Session:      clientData.ss,
+			TrackID:      clientData.trackID,
+			Packet:       out0.Packet,
+			PTSEqualsDTS: out0.PTSEqualsDTS,
+			H264NALUs:    out0.H264NALUs,
+			H264PTS:      out0.H264PTS,
+		})
 	}
 }