update examples to support H264 tracks without SPS/PPS

examples/client-read-h264-convert-to-jpeg/main.go

@@ -63,15 +63,15 @@ func main() {
 	}
 
 	// find the H264 track
-	h264tr, h264trID := func() (*gortsplib.TrackH264, int) {
+	h264TrackID, h264track := func() (int, *gortsplib.TrackH264) {
 		for i, track := range tracks {
-			if h264tr, ok := track.(*gortsplib.TrackH264); ok {
+			if h264track, ok := track.(*gortsplib.TrackH264); ok {
-				return h264tr, i
+				return i, h264track
 			}
 		}
-		return nil, -1
+		return -1, nil
 	}()
-	if h264trID < 0 {
+	if h264TrackID < 0 {
 		panic("H264 track not found")
 	}
 
@@ -86,17 +86,18 @@ func main() {
 	}
 	defer h264dec.close()
 
-	// send SPS and PPS to the decoder
+	// if present, send SPS and PPS from the SDP to the decoder
-	if h264tr.SPS() == nil || h264tr.PPS() == nil {
+	if h264track.SPS() != nil {
-		panic("SPS or PPS not present into the SDP")
+		h264dec.decode(h264track.SPS())
+	}
+	if h264track.PPS() != nil {
+		h264dec.decode(h264track.PPS())
 	}
-	h264dec.decode(h264tr.SPS())
-	h264dec.decode(h264tr.PPS())
 
 	// called when a RTP packet arrives
 	saveCount := 0
 	c.OnPacketRTP = func(trackID int, pkt *rtp.Packet) {
-		if trackID != h264trID {
+		if trackID != h264TrackID {
 			return
 		}
 

examples/client-read-h264-save-to-disk/main.go

@@ -35,19 +35,15 @@ func main() {
 	}
 
 	// find the H264 track
-	var sps []byte
+	h264TrackID, h264track := func() (int, *gortsplib.TrackH264) {
-	var pps []byte
-	h264Track := func() int {
 		for i, track := range tracks {
-			if h264t, ok := track.(*gortsplib.TrackH264); ok {
+			if h264track, ok := track.(*gortsplib.TrackH264); ok {
-				sps = h264t.SPS()
+				return i, h264track
-				pps = h264t.PPS()
-				return i
 			}
 		}
-		return -1
+		return -1, nil
 	}()
-	if h264Track < 0 {
+	if h264TrackID < 0 {
 		panic("H264 track not found")
 	}
 
@@ -56,14 +52,14 @@ func main() {
 	rtpDec.Init()
 
 	// setup H264->MPEGTS encoder
-	enc, err := newMPEGTSEncoder(sps, pps)
+	enc, err := newMPEGTSEncoder(h264track.SPS(), h264track.PPS())
 	if err != nil {
 		panic(err)
 	}
 
 	// called when a RTP packet arrives
 	c.OnPacketRTP = func(trackID int, pkt *rtp.Packet) {
-		if trackID != h264Track {
+		if trackID != h264TrackID {
 			return
 		}
 

examples/client-read-h264-save-to-disk/mpegtsencoder.go

@@ -3,7 +3,6 @@ package main
 import (
 	"bufio"
 	"context"
-	"fmt"
 	"log"
 	"os"
 	"time"
@@ -27,10 +26,6 @@ type mpegtsEncoder struct {
 
 // newMPEGTSEncoder allocates a mpegtsEncoder.
 func newMPEGTSEncoder(sps []byte, pps []byte) (*mpegtsEncoder, error) {
-	if sps == nil || pps == nil {
-		return nil, fmt.Errorf("SPS or PPS not provided")
-	}
-
 	f, err := os.Create("mystream.ts")
 	if err != nil {
 		return nil, err
@@ -84,21 +79,32 @@ func (e *mpegtsEncoder) encode(nalus [][]byte, pts time.Duration) error {
 	}
 
 	for _, nalu := range nalus {
-
 		typ := h264.NALUType(nalu[0] & 0x1F)
 		switch typ {
-		case h264.NALUTypeSPS, h264.NALUTypePPS, h264.NALUTypeAccessUnitDelimiter:
+		case h264.NALUTypeSPS:
-			// remove existing SPS, PPS, AUD
+			e.sps = append([]byte(nil), nalu...)
+
+		case h264.NALUTypePPS:
+			e.pps = append([]byte(nil), nalu...)
+
+		case h264.NALUTypeAccessUnitDelimiter, h264.NALUTypeSEI:
 			continue
 
 		case h264.NALUTypeIDR:
 			// add SPS and PPS before every IDR
-			filteredNALUs = append(filteredNALUs, e.sps, e.pps)
+			if e.sps != nil && e.pps != nil {
+				filteredNALUs = append(filteredNALUs, e.sps, e.pps)
+			}
 		}
 
 		filteredNALUs = append(filteredNALUs, nalu)
 	}
 
+	// it's useless to go on if SPS or PPS have not been provided yet
+	if e.sps == nil || e.pps == nil {
+		return nil
+	}
+
 	// encode into Annex-B
 	enc, err := h264.EncodeAnnexB(filteredNALUs)
 	if err != nil {

examples/client-read-h264/main.go

@@ -40,15 +40,15 @@ func main() {
 	}
 
 	// find the H264 track
-	h264tr, h264trID := func() (*gortsplib.TrackH264, int) {
+	h264TrackID, h264track := func() (int, *gortsplib.TrackH264) {
 		for i, track := range tracks {
-			if h264tr, ok := track.(*gortsplib.TrackH264); ok {
+			if h264track, ok := track.(*gortsplib.TrackH264); ok {
-				return h264tr, i
+				return i, h264track
 			}
 		}
-		return nil, -1
+		return -1, nil
 	}()
-	if h264trID < 0 {
+	if h264TrackID < 0 {
 		panic("H264 track not found")
 	}
 
@@ -63,16 +63,17 @@ func main() {
 	}
 	defer h264dec.close()
 
-	// send SPS and PPS to the decoder
+	// if present, send SPS and PPS from the SDP to the decoder
-	if h264tr.SPS() == nil || h264tr.PPS() == nil {
+	if h264track.SPS() != nil {
-		panic("SPS or PPS not present into the SDP")
+		h264dec.decode(h264track.SPS())
+	}
+	if h264track.PPS() != nil {
+		h264dec.decode(h264track.PPS())
 	}
-	h264dec.decode(h264tr.SPS())
-	h264dec.decode(h264tr.PPS())
 
 	// called when a RTP packet arrives
 	c.OnPacketRTP = func(trackID int, pkt *rtp.Packet) {
-		if trackID != h264trID {
+		if trackID != h264TrackID {
 			return
 		}