insert TrackId and StreamType directly into InterleavedFrame

examples/client-tcp.go

@@ -58,7 +58,7 @@ func main() {
 			panic(err)
 		}
 
-		trackId, streamType := gortsplib.ConvChannelToTrackIdAndStreamType(frame.Channel)
-		fmt.Printf("packet from track %d, type %v: %v\n", trackId, streamType, frame.Content)
+		fmt.Printf("packet from track %d, type %v: %v\n",
+			frame.TrackId, frame.StreamType, frame.Content)
 	}
 }

go.mod

@@ -3,7 +3,8 @@ module github.com/aler9/gortsplib
 go 1.13
 
 require (
+	github.com/pion/rtcp v1.2.3
 	github.com/pion/sdp v1.3.0
 	github.com/pkg/errors v0.9.1 // indirect
-	github.com/stretchr/testify v1.4.0
+	github.com/stretchr/testify v1.5.1
 )

go.sum

@@ -1,5 +1,7 @@
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pion/rtcp v1.2.3 h1:2wrhKnqgSz91Q5nzYTO07mQXztYPtxL8a0XOss4rJqA=
+github.com/pion/rtcp v1.2.3/go.mod h1:zGhIv0RPRF0Z1Wiij22pUt5W/c9fevqSzT4jje/oK7I=
 github.com/pion/sdp v1.3.0 h1:21lpgEILHyolpsIrbCBagZaAPj4o057cFjzaFebkVOs=
 github.com/pion/sdp v1.3.0/go.mod h1:ceA2lTyftydQTuCIbUNoH77aAt6CiQJaRpssA4Gee8I=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
@@ -7,8 +9,8 @@ github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINE
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
-github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=

interleaved-frame.go

@@ -22,26 +22,27 @@ const (
 	StreamTypeRtcp
 )
 
-// ConvChannelToTrackIdAndStreamType converts a channel into a track id and a streamType.
-func ConvChannelToTrackIdAndStreamType(channel uint8) (int, StreamType) {
-	if (channel % 2) == 0 {
-		return int(channel / 2), StreamTypeRtp
+func (st StreamType) String() string {
+	switch st {
+	case StreamTypeRtp:
+		return "RTP"
+
+	case StreamTypeRtcp:
+		return "RTCP"
 	}
-	return int((channel - 1) / 2), StreamTypeRtcp
+	return "UNKNOWN"
 }
 
-// ConvTrackIdAndStreamTypeToChannel converts a track id and a streamType into a channel.
-func ConvTrackIdAndStreamTypeToChannel(trackId int, StreamType StreamType) uint8 {
-	if StreamType == StreamTypeRtp {
-		return uint8(trackId * 2)
-	}
-	return uint8((trackId * 2) + 1)
-}
-
-// InterleavedFrame is a structure that allows to send and receive binary data
-// within RTSP connections. It is usually deployed to send RTP and RTCP packets via TCP.
+// InterleavedFrame is an object that allows to send and receive binary data
+// within RTSP connections. It is used to send RTP and RTCP packets via TCP.
 type InterleavedFrame struct {
-	Channel uint8
+	// track id
+	TrackId int
+
+	// stream type
+	StreamType StreamType
+
+	// frame content
 	Content []byte
 }
 
@@ -62,19 +63,34 @@ func (f *InterleavedFrame) read(r io.Reader) error {
 			framelen, len(f.Content))
 	}
 
-	f.Channel = header[1]
+	// convert channel into TrackId and StreamType
+	channel := header[1]
+	f.TrackId, f.StreamType = func() (int, StreamType) {
+		if (channel % 2) == 0 {
+			return int(channel / 2), StreamTypeRtp
+		}
+		return int((channel - 1) / 2), StreamTypeRtcp
+	}()
+
 	f.Content = f.Content[:framelen]
 
 	_, err = io.ReadFull(r, f.Content)
 	if err != nil {
 		return err
 	}
-
 	return nil
 }
 
 func (f *InterleavedFrame) write(bw *bufio.Writer) error {
-	_, err := bw.Write([]byte{0x24, f.Channel})
+	// convert TrackId and StreamType into channel
+	channel := func() uint8 {
+		if f.StreamType == StreamTypeRtp {
+			return uint8(f.TrackId * 2)
+		}
+		return uint8((f.TrackId * 2) + 1)
+	}()
+
+	_, err := bw.Write([]byte{0x24, channel})
 	if err != nil {
 		return err
 	}