Add packetizer category

audio/packetizer/adts.go

@@ -31,6 +31,10 @@ func (p *AdtsPacket) GetEndSampleNumber() int64 {
 	return p.sampleNumber + adtsFrameSamples
 }
 
+func (p *AdtsPacket) Category() int64 {
+	return 0
+}
+
 func (p *AdtsPacket) GetData() []byte {
 	return append(p.header.Encode(), p.data...)
 }

audio/packetizer/flac.go

@@ -38,6 +38,10 @@ func (p *FLACPacket) GetData() []byte {
 	return p.data
 }
 
+func (p *FLACPacket) Category() int64 {
+	return 0
+}
+
 func NewFLACPacketizer(reader io.Reader) *FLACPacketizer {
 	return &FLACPacketizer{reader: bufio.NewReader(reader)}
 }

audio/packetizer/mp3.go

@@ -28,6 +28,10 @@ func (p *Mp3Packet) GetEndSampleNumber() int64 {
 	return p.sampleNumber + int64(p.frame.Samples())
 }
 
+func (p *Mp3Packet) Category() int64 {
+	return 0
+}
+
 func (p *Mp3Packet) GetData() []byte {
 	return p.frame.Bytes()
 }

audio/packetizer/ogg.go

@@ -43,6 +43,10 @@ func (p *OggPacket) GetEndSampleNumber() int64 {
 	return p.header.AbsoluteGranulePosition
 }
 
+func (p *OggPacket) Category() int64 {
+	return int64(p.header.StreamSerialNumber)
+}
+
 func (p *OggPacket) GetData() []byte {
 	buf := bytes.NewBuffer(make([]byte, 0, 4+1+1+8+4+4+4+1+int(p.header.PageSegments)*(255+1)))
 	binary.Write(buf, binary.LittleEndian, p.header)

audio/packetizer/packetizer.go

@@ -12,6 +12,7 @@ const (
 
 type Packet interface {
 	KeepMode() KeepMode
+	Category() int64
 	GetStartSampleNumber() int64
 	GetEndSampleNumber() int64
 	GetData() []byte