fix clock rate computation with standard RTP payload type (https://github.com/aler9/rtsp-simple-server/issues/123)

track.go

@@ -109,18 +109,44 @@ func NewTrackAAC(id int, config []byte) (*Track, error) {
 
 // ClockRate returns the clock rate of the track.
 func (t *Track) ClockRate() (int, error) {
+	if len(t.Media.MediaName.Formats) != 1 {
+		return 0, fmt.Errorf("invalid format (%v)", t.Media.MediaName.Formats)
+	}
+
+	// get clock rate from payload type
+	switch t.Media.MediaName.Formats[0] {
+	case "0", "1", "2", "3", "4", "5", "7", "8", "9", "12", "13", "15", "18":
+		return 8000, nil
+
+	case "6":
+		return 16000, nil
+
+	case "10", "11":
+		return 44100, nil
+
+	case "14", "25", "26", "28", "31", "32", "33", "34":
+		return 90000, nil
+
+	case "16":
+		return 11025, nil
+
+	case "17":
+		return 22050, nil
+	}
+
+	// get clock rate from rtpmap
 	// https://tools.ietf.org/html/rfc4566
 	// a=rtpmap:<payload type> <encoding name>/<clock rate> [/<encoding parameters>]
 	for _, a := range t.Media.Attributes {
 		if a.Key == "rtpmap" {
 			tmp := strings.Split(a.Value, " ")
-			if len(tmp) != 2 {
-				return 0, fmt.Errorf("invalid format (%s)", a.Value)
+			if len(tmp) < 2 {
+				return 0, fmt.Errorf("invalid rtpmap (%v)", a.Value)
 			}
 
 			tmp = strings.Split(tmp[1], "/")
 			if len(tmp) != 2 && len(tmp) != 3 {
-				return 0, fmt.Errorf("invalid format (%s)", a.Value)
+				return 0, fmt.Errorf("invalid rtpmap (%v)", a.Value)
 			}
 
 			v, err := strconv.ParseInt(tmp[1], 10, 64)

track_test.go

@@ -0,0 +1,84 @@
+package gortsplib
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestTrackClockRate(t *testing.T) {
+	for _, ca := range []struct {
+		name      string
+		sdp       []byte
+		clockRate int
+	}{
+		{
+			"empty encoding parameters",
+			[]byte("v=0\r\n" +
+				"o=- 38990265062388 38990265062388 IN IP4 192.168.1.142\r\n" +
+				"s=RTSP Session\r\n" +
+				"c=IN IP4 192.168.1.142\r\n" +
+				"t=0 0\r\n" +
+				"a=control:*\r\n" +
+				"a=range:npt=0-\r\n" +
+				"m=video 0 RTP/AVP 96\r\n" +
+				"a=rtpmap:96 H264/90000 \r\n" +
+				"a=range:npt=0-\r\n" +
+				"a=framerate:0S\r\n" +
+				"a=fmtp:96 profile-level-id=64000c; packetization-mode=1; sprop-parameter-sets=Z2QADKw7ULBLQgAAAwACAAADAD0I,aO48gA==\r\n" +
+				"a=framerate:25\r\n" +
+				"a=control:trackID=3\r\n"),
+			90000,
+		},
+		{
+			"static payload type 1",
+			[]byte("v=0\r\n" +
+				"o=- 38990265062388 38990265062388 IN IP4 192.168.1.142\r\n" +
+				"s=RTSP Session\r\n" +
+				"c=IN IP4 192.168.1.142\r\n" +
+				"t=0 0\r\n" +
+				"a=control:*\r\n" +
+				"a=range:npt=0-\r\n" +
+				"m=audio 0 RTP/AVP 8\r\n" +
+				"a=control:trackID=4"),
+			8000,
+		},
+		{
+			"static payload type 2",
+			[]byte("v=0\r\n" +
+				"o=jdoe 2890844526 2890842807 IN IP4 10.47.16.5\r\n" +
+				"s=SDP Seminar\r\n" +
+				"i=A Seminar on the session description protocol\r\n" +
+				"u=http://www.example.com/seminars/sdp.pdf\r\n" +
+				"e=j.doe@example.com (Jane Doe)\r\n" +
+				"p=+1 617 555-6011\r\n" +
+				"c=IN IP4 224.2.17.12/127\r\n" +
+				"b=X-YZ:128\r\n" +
+				"b=AS:12345\r\n" +
+				"t=2873397496 2873404696\r\n" +
+				"t=3034423619 3042462419\r\n" +
+				"r=604800 3600 0 90000\r\n" +
+				"z=2882844526 -3600 2898848070 0\r\n" +
+				"k=prompt\r\n" +
+				"a=candidate:0 1 UDP 2113667327 203.0.113.1 54400 typ host\r\n" +
+				"a=recvonly\r\n" +
+				"m=audio 49170 RTP/AVP 0\r\n" +
+				"i=Vivamus a posuere nisl\r\n" +
+				"c=IN IP4 203.0.113.1\r\n" +
+				"b=X-YZ:128\r\n" +
+				"k=prompt\r\n" +
+				"a=sendrecv\r\n"),
+			8000,
+		},
+	} {
+		t.Run(ca.name, func(t *testing.T) {
+			tracks, err := ReadTracks(ca.sdp)
+			require.NoError(t, err)
+
+			clockRate, err := tracks[0].ClockRate()
+			require.NoError(t, err)
+
+			require.Equal(t, clockRate, ca.clockRate)
+		})
+	}
+}