add G726 format (#330)

README.md

@@ -100,35 +100,36 @@ In RTSP, media streams are routed between server and clients by using RTP packet
 
 ### Video
 
-|codec|rtp format|documentation|encoder and decoder available|
+|format / codec|variant|documentation|encoder and decoder available|
-|-----|----------|-------------|-----------------------------|
+|--------------|-------|-------------|-----------------------------|
-|AV1|AV1|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#AV1)|:heavy_check_mark:|
+|AV1||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#AV1)|:heavy_check_mark:|
-|VP9|VP9|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#VP9)|:heavy_check_mark:|
+|VP9||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#VP9)|:heavy_check_mark:|
-|VP8|VP8|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#VP8)|:heavy_check_mark:|
+|VP8||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#VP8)|:heavy_check_mark:|
-|H265|H265|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#H265)|:heavy_check_mark:|
+|H265||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#H265)|:heavy_check_mark:|
-|H264|H264|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#H264)|:heavy_check_mark:|
+|H264||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#H264)|:heavy_check_mark:|
-|MPEG-2 Video|unnamed|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG2Video)||
+|MPEG-4 Video (H263, Xvid)||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG4VideoES)|:heavy_check_mark:|
-|MPEG-4 Video (H263, Xvid)|MP4V-ES|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG4VideoES)|:heavy_check_mark:|
+|MPEG-2 Video||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG2Video)||
-|M-JPEG|JPEG|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MJPEG)|:heavy_check_mark:|
+|M-JPEG||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MJPEG)|:heavy_check_mark:|
 
 ### Audio
 
-|codec|rtp format|documentation|encoder and decoder available|
+|format / codec|variant|documentation|encoder and decoder available|
-|-----|----------|-------------|-----------------------------|
+|--------------|-------|-------------|-----------------------------|
-|Opus|opus|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#Opus)|:heavy_check_mark:|
+|Opus||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#Opus)|:heavy_check_mark:|
-|Vorbis|VORBIS|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#Vorbis)||
+|Vorbis||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#Vorbis)||
-|MPEG-4 Audio (AAC)|mpeg4-generic|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG4AudioGeneric)|:heavy_check_mark:|
+|MPEG-4 Audio (AAC)|Generic (RFC3640)|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG4AudioGeneric)|:heavy_check_mark:|
-|MPEG-4 Audio (AAC)|MP4A-LATM|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG4AudioLATM)|:heavy_check_mark:|
+|MPEG-4 Audio (AAC)|LATM (RFC6416)|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG4AudioLATM)|:heavy_check_mark:|
-|MPEG-1/2 Audio (MP3)|unnamed|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG2Audio)|:heavy_check_mark:|
+|MPEG-1/2 Audio (MP3)||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEG2Audio)|:heavy_check_mark:|
-|G722|unnamed|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#G722)|:heavy_check_mark:|
+|G726||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#G726)||
-|G711 (PCMA, PCMU)|unnamed|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#G711)|:heavy_check_mark:|
+|G722||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#G722)|:heavy_check_mark:|
-|LPCM|L8/L16/L24|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#LPCM)|:heavy_check_mark:|
+|G711 (PCMA, PCMU)||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#G711)|:heavy_check_mark:|
+|LPCM||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#LPCM)|:heavy_check_mark:|
 
 ### Mixed
 
-|codec|rtp format|documentation|encoder and decoder available|
+|format / codec|variant|documentation|encoder and decoder available|
-|-----|----------|-------------|-----------------------------|
+|--------------|-------|-------------|-----------------------------|
-|MPEG-TS|MP2T|[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEGTS)||
+|MPEG-TS||[link](https://pkg.go.dev/github.com/bluenviron/gortsplib/v3/pkg/formats#MPEGTS)||
 
 ## Standards
 

pkg/formats/format.go

@@ -87,6 +87,16 @@ func Unmarshal(mediaType string, payloadType uint8, rtpMap string, fmtp map[stri
 			case payloadType == 9:
 				return &G722{}
 
+			case (codec == "g726-16" ||
+				codec == "g726-24" ||
+				codec == "g726-32" ||
+				codec == "g726-40" ||
+				codec == "aal2-g726-16" ||
+				codec == "aal2-g726-24" ||
+				codec == "aal2-g726-32" ||
+				codec == "aal2-g726-40") && clock == "8000":
+				return &G726{}
+
 			case payloadType == 14:
 				return &MPEG2Audio{}
 

pkg/formats/format_test.go

@@ -58,6 +58,72 @@ var casesFormat = []struct {
 		"G722/8000",
 		nil,
 	},
+	{
+		"audio g726 le 1",
+		"audio",
+		97,
+		"G726-16/8000",
+		nil,
+		&G726{
+			PayloadTyp: 97,
+			BitRate:    16,
+		},
+		"G726-16/8000",
+		nil,
+	},
+	{
+		"audio g726 le 2",
+		"audio",
+		97,
+		"G726-24/8000",
+		nil,
+		&G726{
+			PayloadTyp: 97,
+			BitRate:    24,
+		},
+		"G726-24/8000",
+		nil,
+	},
+	{
+		"audio g726 le 3",
+		"audio",
+		97,
+		"G726-32/8000",
+		nil,
+		&G726{
+			PayloadTyp: 97,
+			BitRate:    32,
+		},
+		"G726-32/8000",
+		nil,
+	},
+	{
+		"audio g726 le 4",
+		"audio",
+		97,
+		"G726-40/8000",
+		nil,
+		&G726{
+			PayloadTyp: 97,
+			BitRate:    40,
+		},
+		"G726-40/8000",
+		nil,
+	},
+	{
+		"audio g726 be",
+		"audio",
+		97,
+		"AAL2-G726-32/8000",
+		nil,
+		&G726{
+			PayloadTyp: 97,
+			BitRate:    32,
+			BigEndian:  true,
+		},
+		"AAL2-G726-32/8000",
+		nil,
+	},
 	{
 		"audio lpcm 8",
 		"audio",

pkg/formats/g726.go

@@ -0,0 +1,80 @@
+package formats
+
+import (
+	"strconv"
+	"strings"
+
+	"github.com/pion/rtp"
+)
+
+// G726 is a RTP format for the G726 codec.
+// Specification: https://datatracker.ietf.org/doc/html/rfc3551
+type G726 struct {
+	PayloadTyp uint8
+	BitRate    int
+	BigEndian  bool
+}
+
+func (f *G726) unmarshal(payloadType uint8, _ string, codec string, _ string, _ map[string]string) error {
+	f.PayloadTyp = payloadType
+
+	if strings.HasPrefix(codec, "aal2-") {
+		f.BigEndian = true
+	}
+
+	switch {
+	case strings.HasSuffix(codec, "-16"):
+		f.BitRate = 16
+	case strings.HasSuffix(codec, "-24"):
+		f.BitRate = 24
+	case strings.HasSuffix(codec, "-32"):
+		f.BitRate = 32
+	default:
+		f.BitRate = 40
+	}
+
+	return nil
+}
+
+// Codec implements Format.
+func (f *G726) Codec() string {
+	return "G726"
+}
+
+// String implements Format.
+//
+// Deprecated: replaced by Codec().
+func (f *G726) String() string {
+	return f.Codec()
+}
+
+// ClockRate implements Format.
+func (f *G726) ClockRate() int {
+	return 8000
+}
+
+// PayloadType implements Format.
+func (f *G726) PayloadType() uint8 {
+	return f.PayloadTyp
+}
+
+// RTPMap implements Format.
+func (f *G726) RTPMap() string {
+	codec := ""
+
+	if f.BigEndian {
+		codec += "AAL2-"
+	}
+
+	return codec + "G726-" + strconv.FormatInt(int64(f.BitRate), 10) + "/8000"
+}
+
+// FMTP implements Format.
+func (f *G726) FMTP() map[string]string {
+	return nil
+}
+
+// PTSEqualsDTS implements Format.
+func (f *G726) PTSEqualsDTS(*rtp.Packet) bool {
+	return true
+}

pkg/formats/g726_test.go

@@ -0,0 +1,15 @@
+package formats
+
+import (
+	"testing"
+
+	"github.com/pion/rtp"
+	"github.com/stretchr/testify/require"
+)
+
+func TestG726Attributes(t *testing.T) {
+	format := &G726{}
+	require.Equal(t, "G726", format.Codec())
+	require.Equal(t, 8000, format.ClockRate())
+	require.Equal(t, true, format.PTSEqualsDTS(&rtp.Packet{}))
+}