improve client-read examples in order to setup only needed tracks

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

@@ -62,15 +62,15 @@ func main() {
 	}
 
 	// find the H264 track
-	h264TrackID, h264track := func() (int, *gortsplib.TrackH264) {
+	h264track := func() *gortsplib.TrackH264 {
-		for i, track := range tracks {
+		for _, track := range tracks {
 			if h264track, ok := track.(*gortsplib.TrackH264); ok {
-				return i, h264track
+				return h264track
 			}
 		}
-		return -1, nil
+		return nil
 	}()
-	if h264TrackID < 0 {
+	if h264track == nil {
 		panic("H264 track not found")
 	}
 
@@ -98,10 +98,6 @@ func main() {
 	// called when a RTP packet arrives
 	saveCount := 0
 	c.OnPacketRTP = func(ctx *gortsplib.ClientOnPacketRTPCtx) {
-		if ctx.TrackID != h264TrackID {
-			return
-		}
-
 		// convert RTP packets into NALUs
 		nalus, _, err := rtpDec.Decode(ctx.Packet)
 		if err != nil {
@@ -134,8 +130,8 @@ func main() {
 		}
 	}
 
-	// setup and read all tracks
+	// setup and read the H264 track only
-	err = c.SetupAndPlay(tracks, baseURL)
+	err = c.SetupAndPlay(gortsplib.Tracks{h264track}, baseURL)
 	if err != nil {
 		panic(err)
 	}

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

@@ -34,15 +34,15 @@ func main() {
 	}
 
 	// find the H264 track
-	h264TrackID, h264track := func() (int, *gortsplib.TrackH264) {
+	track := func() *gortsplib.TrackH264 {
-		for i, track := range tracks {
+		for _, track := range tracks {
-			if h264track, ok := track.(*gortsplib.TrackH264); ok {
+			if track, ok := track.(*gortsplib.TrackH264); ok {
-				return i, h264track
+				return track
 			}
 		}
-		return -1, nil
+		return nil
 	}()
-	if h264TrackID < 0 {
+	if track == nil {
 		panic("H264 track not found")
 	}
 
@@ -51,17 +51,13 @@ func main() {
 	rtpDec.Init()
 
 	// setup H264->MPEGTS muxer
-	mpegtsMuxer, err := newMPEGTSMuxer(h264track.SafeSPS(), h264track.SafePPS())
+	mpegtsMuxer, err := newMPEGTSMuxer(track.SafeSPS(), track.SafePPS())
 	if err != nil {
 		panic(err)
 	}
 
 	// called when a RTP packet arrives
 	c.OnPacketRTP = func(ctx *gortsplib.ClientOnPacketRTPCtx) {
-		if ctx.TrackID != h264TrackID {
-			return
-		}
-
 		// convert RTP packets into NALUs
 		nalus, pts, err := rtpDec.Decode(ctx.Packet)
 		if err != nil {
@@ -72,8 +68,8 @@ func main() {
 		mpegtsMuxer.encode(nalus, pts)
 	}
 
-	// setup and read all tracks
+	// setup and read the H264 track only
-	err = c.SetupAndPlay(tracks, baseURL)
+	err = c.SetupAndPlay(gortsplib.Tracks{track}, baseURL)
 	if err != nil {
 		panic(err)
 	}

examples/client-read-codec-h264/main.go

@@ -39,15 +39,15 @@ func main() {
 	}
 
 	// find the H264 track
-	h264TrackID, h264track := func() (int, *gortsplib.TrackH264) {
+	track := func() *gortsplib.TrackH264 {
-		for i, track := range tracks {
+		for _, track := range tracks {
-			if h264track, ok := track.(*gortsplib.TrackH264); ok {
+			if track, ok := track.(*gortsplib.TrackH264); ok {
-				return i, h264track
+				return track
 			}
 		}
-		return -1, nil
+		return nil
 	}()
-	if h264TrackID < 0 {
+	if track == nil {
 		panic("H264 track not found")
 	}
 
@@ -63,21 +63,17 @@ func main() {
 	defer h264RawDec.close()
 
 	// if SPS and PPS are present into the SDP, send them to the decoder
-	sps := h264track.SafeSPS()
+	sps := track.SafeSPS()
 	if sps != nil {
 		h264RawDec.decode(sps)
 	}
-	pps := h264track.SafePPS()
+	pps := track.SafePPS()
 	if pps != nil {
 		h264RawDec.decode(pps)
 	}
 
 	// called when a RTP packet arrives
 	c.OnPacketRTP = func(ctx *gortsplib.ClientOnPacketRTPCtx) {
-		if ctx.TrackID != h264TrackID {
-			return
-		}
-
 		// convert RTP packets into NALUs
 		nalus, _, err := rtpDec.Decode(ctx.Packet)
 		if err != nil {
@@ -100,8 +96,8 @@ func main() {
 		}
 	}
 
-	// setup and read all tracks
+	// setup and read the H264 track only
-	err = c.SetupAndPlay(tracks, baseURL)
+	err = c.SetupAndPlay(gortsplib.Tracks{track}, baseURL)
 	if err != nil {
 		panic(err)
 	}

examples/client-read-codec-mpeg4audio/main.go

@@ -36,33 +36,29 @@ func main() {
 	}
 
 	// find the MPEG4-audio track
-	mpeg4audioTrack, mpeg4audioTrackID := func() (*gortsplib.TrackMPEG4Audio, int) {
+	track := func() *gortsplib.TrackMPEG4Audio {
-		for i, track := range tracks {
+		for _, track := range tracks {
 			if tt, ok := track.(*gortsplib.TrackMPEG4Audio); ok {
-				return tt, i
+				return tt
 			}
 		}
-		return nil, -1
+		return nil
 	}()
-	if mpeg4audioTrack == nil {
+	if track == nil {
 		panic("MPEG4-audio track not found")
 	}
 
 	// setup decoder
 	dec := &rtpmpeg4audio.Decoder{
-		SampleRate:       mpeg4audioTrack.Config.SampleRate,
+		SampleRate:       track.Config.SampleRate,
-		SizeLength:       mpeg4audioTrack.SizeLength,
+		SizeLength:       track.SizeLength,
-		IndexLength:      mpeg4audioTrack.IndexLength,
+		IndexLength:      track.IndexLength,
-		IndexDeltaLength: mpeg4audioTrack.IndexDeltaLength,
+		IndexDeltaLength: track.IndexDeltaLength,
 	}
 	dec.Init()
 
 	// called when a RTP packet arrives
 	c.OnPacketRTP = func(ctx *gortsplib.ClientOnPacketRTPCtx) {
-		if ctx.TrackID != mpeg4audioTrackID {
-			return
-		}
-
 		// decode MPEG4-audio AUs from the RTP packet
 		aus, _, err := dec.Decode(ctx.Packet)
 		if err != nil {
@@ -75,8 +71,8 @@ func main() {
 		}
 	}
 
-	// setup and read all tracks
+	// setup and read the MPEG4-audio track only
-	err = c.SetupAndPlay(tracks, baseURL)
+	err = c.SetupAndPlay(gortsplib.Tracks{track}, baseURL)
 	if err != nil {
 		panic(err)
 	}