mpegts, srt: support MPEG-4 Audio LATM tracks (#4403) (#4759)

go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/alecthomas/kong v1.12.0
 	github.com/asticode/go-astits v1.13.0
 	github.com/bluenviron/gohlslib/v2 v2.2.2
-	github.com/bluenviron/gortsplib/v4 v4.15.0
+	github.com/bluenviron/gortsplib/v4 v4.16.0
 	github.com/bluenviron/mediacommon/v2 v2.4.0
 	github.com/datarhei/gosrt v0.9.0
 	github.com/fsnotify/fsnotify v1.9.0

go.sum

@@ -35,8 +35,8 @@ github.com/benburkert/openpgp v0.0.0-20160410205803-c2471f86866c h1:8XZeJrs4+ZYh
 github.com/benburkert/openpgp v0.0.0-20160410205803-c2471f86866c/go.mod h1:x1vxHcL/9AVzuk5HOloOEPrtJY0MaalYr78afXZ+pWI=
 github.com/bluenviron/gohlslib/v2 v2.2.2 h1:Q86VloPjwONKF8pu6jSEh9ENm4UzdMl5SzYvtjneL5k=
 github.com/bluenviron/gohlslib/v2 v2.2.2/go.mod h1:3Lby/VMDD/cN0B3uJPd3bEEiJZ34LqXs71FEvN/fq2k=
-github.com/bluenviron/gortsplib/v4 v4.15.0 h1:R5mimKNlmzpUqcAVfCqkSznGk/2hl4Kk9LPFo2KZJeU=
-github.com/bluenviron/gortsplib/v4 v4.15.0/go.mod h1:mqAxRuombKOUHREiKuKJ4VBjEC4U7VeMar4/G4Sbq04=
+github.com/bluenviron/gortsplib/v4 v4.16.0 h1:qzJxlZXCv11oxNkNTAFMaeX0uEXJE0L6lDv3CKUYT/k=
+github.com/bluenviron/gortsplib/v4 v4.16.0/go.mod h1:pcSNf/GToNEwdWy74moR4Tp5JWIEDJ0d9CzCSUPkiwM=
 github.com/bluenviron/mediacommon/v2 v2.4.0 h1:Ss1T7AMxTrICJ+a/N5urS/1lp1ZpsF+3iJq3B/RLDMw=
 github.com/bluenviron/mediacommon/v2 v2.4.0/go.mod h1:a6MbPmXtYda9mKibKVMZlW20GYLLrX2R7ZkUE+1pwV0=
 github.com/bytedance/sonic v1.13.2 h1:8/H1FempDZqC4VqjptGo14QQlJx8VdZJegxs6wwfqpQ=

internal/formatprocessor/mpeg4_audio_latm.go

@@ -0,0 +1,114 @@
+package formatprocessor
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/bluenviron/gortsplib/v4/pkg/format"
+	"github.com/bluenviron/gortsplib/v4/pkg/format/rtpfragmented"
+	"github.com/bluenviron/gortsplib/v4/pkg/format/rtpmpeg4audio"
+	"github.com/pion/rtp"
+
+	"github.com/bluenviron/mediamtx/internal/logger"
+	"github.com/bluenviron/mediamtx/internal/unit"
+)
+
+type mpeg4AudioLATM struct {
+	RTPMaxPayloadSize  int
+	Format             *format.MPEG4AudioLATM
+	GenerateRTPPackets bool
+	Parent             logger.Writer
+
+	encoder     *rtpfragmented.Encoder
+	decoder     *rtpfragmented.Decoder
+	randomStart uint32
+}
+
+func (t *mpeg4AudioLATM) initialize() error {
+	if t.GenerateRTPPackets {
+		err := t.createEncoder()
+		if err != nil {
+			return err
+		}
+
+		t.randomStart, err = randUint32()
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (t *mpeg4AudioLATM) createEncoder() error {
+	t.encoder = &rtpfragmented.Encoder{
+		PayloadMaxSize: t.RTPMaxPayloadSize,
+		PayloadType:    t.Format.PayloadTyp,
+	}
+	return t.encoder.Init()
+}
+
+func (t *mpeg4AudioLATM) ProcessUnit(uu unit.Unit) error { //nolint:dupl
+	u := uu.(*unit.MPEG4AudioLATM)
+
+	pkts, err := t.encoder.Encode(u.Element)
+	if err != nil {
+		return err
+	}
+	u.RTPPackets = pkts
+
+	for _, pkt := range u.RTPPackets {
+		pkt.Timestamp += t.randomStart + uint32(u.PTS)
+	}
+
+	return nil
+}
+
+func (t *mpeg4AudioLATM) ProcessRTPPacket( //nolint:dupl
+	pkt *rtp.Packet,
+	ntp time.Time,
+	pts int64,
+	hasNonRTSPReaders bool,
+) (unit.Unit, error) {
+	u := &unit.MPEG4AudioLATM{
+		Base: unit.Base{
+			RTPPackets: []*rtp.Packet{pkt},
+			NTP:        ntp,
+			PTS:        pts,
+		},
+	}
+
+	// remove padding
+	pkt.Padding = false
+	pkt.PaddingSize = 0
+
+	if len(pkt.Payload) > t.RTPMaxPayloadSize {
+		return nil, fmt.Errorf("RTP payload size (%d) is greater than maximum allowed (%d)",
+			len(pkt.Payload), t.RTPMaxPayloadSize)
+	}
+
+	// decode from RTP
+	if hasNonRTSPReaders || t.decoder != nil {
+		if t.decoder == nil {
+			var err error
+			t.decoder, err = t.Format.CreateDecoder()
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		el, err := t.decoder.Decode(pkt)
+		if err != nil {
+			if errors.Is(err, rtpmpeg4audio.ErrMorePacketsNeeded) {
+				return u, nil
+			}
+			return nil, err
+		}
+
+		u.Element = el
+	}
+
+	// route packet as is
+	return u, nil
+}

internal/formatprocessor/mpeg4_video.go

@@ -7,7 +7,7 @@ import (
 	"time"
 
 	"github.com/bluenviron/gortsplib/v4/pkg/format"
-	"github.com/bluenviron/gortsplib/v4/pkg/format/rtpmpeg4video"
+	"github.com/bluenviron/gortsplib/v4/pkg/format/rtpfragmented"
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4video"
 	"github.com/pion/rtp"
 
@@ -33,8 +33,8 @@ type mpeg4Video struct {
 	GenerateRTPPackets bool
 	Parent             logger.Writer
 
-	encoder     *rtpmpeg4video.Encoder
-	decoder     *rtpmpeg4video.Decoder
+	encoder     *rtpfragmented.Encoder
+	decoder     *rtpfragmented.Decoder
 	randomStart uint32
 }
 
@@ -55,7 +55,7 @@ func (t *mpeg4Video) initialize() error {
 }
 
 func (t *mpeg4Video) createEncoder() error {
-	t.encoder = &rtpmpeg4video.Encoder{
+	t.encoder = &rtpfragmented.Encoder{
 		PayloadMaxSize: t.RTPMaxPayloadSize,
 		PayloadType:    t.Format.PayloadTyp,
 	}
@@ -154,7 +154,7 @@ func (t *mpeg4Video) ProcessRTPPacket( //nolint:dupl
 
 		frame, err := t.decoder.Decode(pkt)
 		if err != nil {
-			if errors.Is(err, rtpmpeg4video.ErrMorePacketsNeeded) {
+			if errors.Is(err, rtpfragmented.ErrMorePacketsNeeded) {
 				return u, nil
 			}
 			return nil, err

internal/formatprocessor/processor.go

@@ -135,6 +135,14 @@ func New(
 			Parent:             parent,
 		}
 
+	case *format.MPEG4AudioLATM:
+		proc = &mpeg4AudioLATM{
+			RTPMaxPayloadSize:  rtpMaxPayloadSize,
+			Format:             forma,
+			GenerateRTPPackets: generateRTPPackets,
+			Parent:             parent,
+		}
+
 	case *format.MPEG1Audio:
 		proc = &mpeg1Audio{
 			RTPMaxPayloadSize:  rtpMaxPayloadSize,

internal/protocols/hls/from_stream.go

@@ -9,6 +9,7 @@ import (
 	"github.com/bluenviron/gohlslib/v2/pkg/codecs"
 	"github.com/bluenviron/gortsplib/v4/pkg/description"
 	"github.com/bluenviron/gortsplib/v4/pkg/format"
+	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4audio"
 	"github.com/bluenviron/mediamtx/internal/logger"
 	"github.com/bluenviron/mediamtx/internal/stream"
 	"github.com/bluenviron/mediamtx/internal/unit"
@@ -233,11 +234,41 @@ func setupAudioTracks(
 					})
 
 			case *format.MPEG4Audio:
-				co := forma.GetConfig()
-				if co != nil {
+				track := &gohlslib.Track{
+					Codec: &codecs.MPEG4Audio{
+						Config: *forma.Config,
+					},
+					ClockRate: forma.ClockRate(),
+				}
+
+				addTrack(
+					media,
+					forma,
+					track,
+					func(u unit.Unit) error {
+						tunit := u.(*unit.MPEG4Audio)
+
+						if tunit.AUs == nil {
+							return nil
+						}
+
+						err := muxer.WriteMPEG4Audio(
+							track,
+							tunit.NTP,
+							tunit.PTS, // no conversion is needed since we set gohlslib.Track.ClockRate = format.ClockRate
+							tunit.AUs)
+						if err != nil {
+							return fmt.Errorf("muxer error: %w", err)
+						}
+
+						return nil
+					})
+
+			case *format.MPEG4AudioLATM:
+				if !forma.CPresent {
 					track := &gohlslib.Track{
 						Codec: &codecs.MPEG4Audio{
-							Config: *co,
+							Config: *forma.StreamMuxConfig.Programs[0].Layers[0].AudioSpecificConfig,
 						},
 						ClockRate: forma.ClockRate(),
 					}
@@ -247,22 +278,24 @@ func setupAudioTracks(
 						forma,
 						track,
 						func(u unit.Unit) error {
-							tunit := u.(*unit.MPEG4Audio)
+							tunit := u.(*unit.MPEG4AudioLATM)
 
-							if tunit.AUs == nil {
+							if tunit.Element == nil {
 								return nil
 							}
 
-							err := muxer.WriteMPEG4Audio(
+							var ame mpeg4audio.AudioMuxElement
+							ame.StreamMuxConfig = forma.StreamMuxConfig
+							err := ame.Unmarshal(tunit.Element)
+							if err != nil {
+								return err
+							}
+
+							return muxer.WriteMPEG4Audio(
 								track,
 								tunit.NTP,
 								tunit.PTS, // no conversion is needed since we set gohlslib.Track.ClockRate = format.ClockRate
-								tunit.AUs)
-							if err != nil {
-								return fmt.Errorf("muxer error: %w", err)
-							}
-
-							return nil
+								[][]byte{ame.Payloads[0][0][0]})
 						})
 				}
 			}

internal/protocols/mpegts/enhanced_reader.go

@@ -0,0 +1,78 @@
+package mpegts
+
+import (
+	"io"
+
+	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4audio"
+	mcmpegts "github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
+	"github.com/bluenviron/mediacommon/v2/pkg/rewindablereader"
+)
+
+// EnhancedReader is a mpegts.Reader wrapper
+// That provides additional informations that are needed in order
+// to perform conversion to RTSP.
+type EnhancedReader struct {
+	R io.Reader
+
+	*mcmpegts.Reader
+
+	latmConfigs map[uint16]*mpeg4audio.StreamMuxConfig
+}
+
+// Initialize initializes EnhancedReader.
+func (r *EnhancedReader) Initialize() error {
+	rr := &rewindablereader.Reader{R: r.R}
+	mr := &mcmpegts.Reader{R: rr}
+	err := mr.Initialize()
+	if err != nil {
+		return err
+	}
+
+	r.latmConfigs = make(map[uint16]*mpeg4audio.StreamMuxConfig)
+	tracksToParse := 0
+
+	for _, track := range mr.Tracks() {
+		if _, ok := track.Codec.(*mcmpegts.CodecMPEG4AudioLATM); ok {
+			cpid := track.PID
+			done := false
+			tracksToParse++
+
+			mr.OnDataMPEG4AudioLATM(track, func(_ int64, els [][]byte) error {
+				if done {
+					return nil
+				}
+
+				var ame mpeg4audio.AudioMuxElement
+				ame.MuxConfigPresent = true
+				err2 := ame.Unmarshal(els[0])
+				if err2 != nil {
+					return nil //nolint:nilerr
+				}
+
+				if ame.MuxConfigPresent {
+					r.latmConfigs[cpid] = ame.StreamMuxConfig
+					tracksToParse--
+					done = true
+				}
+
+				return nil
+			})
+		}
+	}
+
+	for tracksToParse > 0 {
+		err = mr.Read()
+		if err != nil {
+			return err
+		}
+	}
+
+	rr.Rewind()
+	r.Reader = &mcmpegts.Reader{R: rr}
+	err = r.Reader.Initialize()
+	if err != nil {
+		return err
+	}
+
+	return err
+}

internal/protocols/mpegts/from_stream.go

@@ -10,6 +10,7 @@ import (
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/ac3"
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/h264"
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/h265"
+	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4audio"
 	mcmpegts "github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
 	srt "github.com/datarhei/gosrt"
 
@@ -255,27 +256,89 @@ func FromStream(
 					})
 
 			case *format.MPEG4Audio:
-				co := forma.GetConfig()
-				if co != nil {
-					track := &mcmpegts.Track{Codec: &mcmpegts.CodecMPEG4Audio{
-						Config: *co,
-					}}
+				track := &mcmpegts.Track{Codec: &mcmpegts.CodecMPEG4Audio{
+					Config: *forma.Config,
+				}}
 
+				addTrack(
+					media,
+					forma,
+					track,
+					func(u unit.Unit) error {
+						tunit := u.(*unit.MPEG4Audio)
+						if tunit.AUs == nil {
+							return nil
+						}
+
+						sconn.SetWriteDeadline(time.Now().Add(writeTimeout))
+						err := (*w).WriteMPEG4Audio(
+							track,
+							multiplyAndDivide(tunit.PTS, 90000, int64(clockRate)),
+							tunit.AUs)
+						if err != nil {
+							return err
+						}
+						return bw.Flush()
+					})
+
+			case *format.MPEG4AudioLATM:
+				track := &mcmpegts.Track{Codec: &mcmpegts.CodecMPEG4AudioLATM{}}
+
+				if !forma.CPresent {
 					addTrack(
 						media,
 						forma,
 						track,
 						func(u unit.Unit) error {
-							tunit := u.(*unit.MPEG4Audio)
-							if tunit.AUs == nil {
+							tunit := u.(*unit.MPEG4AudioLATM)
+							if tunit.Element == nil {
+								return nil
+							}
+
+							var elIn mpeg4audio.AudioMuxElement
+							elIn.MuxConfigPresent = false
+							elIn.StreamMuxConfig = forma.StreamMuxConfig
+							err := elIn.Unmarshal(tunit.Element)
+							if err != nil {
+								return err
+							}
+
+							var elOut mpeg4audio.AudioMuxElement
+							elOut.MuxConfigPresent = true
+							elOut.StreamMuxConfig = forma.StreamMuxConfig
+							elOut.UseSameStreamMux = false
+							elOut.Payloads = elIn.Payloads
+							buf, err := elOut.Marshal()
+							if err != nil {
+								return err
+							}
+
+							sconn.SetWriteDeadline(time.Now().Add(writeTimeout))
+							err = (*w).WriteMPEG4AudioLATM(
+								track,
+								multiplyAndDivide(tunit.PTS, 90000, int64(clockRate)),
+								[][]byte{buf})
+							if err != nil {
+								return err
+							}
+							return bw.Flush()
+						})
+				} else {
+					addTrack(
+						media,
+						forma,
+						track,
+						func(u unit.Unit) error {
+							tunit := u.(*unit.MPEG4AudioLATM)
+							if tunit.Element == nil {
 								return nil
 							}
 
 							sconn.SetWriteDeadline(time.Now().Add(writeTimeout))
-							err := (*w).WriteMPEG4Audio(
+							err := (*w).WriteMPEG4AudioLATM(
 								track,
 								multiplyAndDivide(tunit.PTS, 90000, int64(clockRate)),
-								tunit.AUs)
+								[][]byte{tunit.Element})
 							if err != nil {
 								return err
 							}
@@ -353,10 +416,5 @@ func FromStream(
 	}
 
 	w = &mcmpegts.Writer{W: bw, Tracks: tracks}
-	err := w.Initialize()
-	if err != nil {
-		panic(err)
-	}
-
-	return nil
+	return w.Initialize()
 }

internal/protocols/mpegts/to_stream.go

@@ -3,10 +3,13 @@ package mpegts
 
 import (
 	"errors"
+	"fmt"
+	"reflect"
 	"time"
 
 	"github.com/bluenviron/gortsplib/v4/pkg/description"
 	"github.com/bluenviron/gortsplib/v4/pkg/format"
+	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4audio"
 	"github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
 
 	"github.com/bluenviron/mediamtx/internal/logger"
@@ -20,7 +23,7 @@ var errNoSupportedCodecs = errors.New(
 
 // ToStream maps a MPEG-TS stream to a MediaMTX stream.
 func ToStream(
-	r *mpegts.Reader,
+	r *EnhancedReader,
 	stream **stream.Stream,
 	l logger.Writer,
 ) ([]*description.Media, error) {
@@ -184,6 +187,64 @@ func ToStream(
 				return nil
 			})
 
+		case *mpegts.CodecMPEG4AudioLATM:
+			// We are dealing with a LATM stream with in-band configuration.
+			// Although in theory this can be streamed with RTSP (RFC6416 with cpresent=1),
+			// in practice there is no player that supports it.
+			// Therefore, convert the stream to a LATM stream with out-of-band configuration.
+			streamMuxConfig := r.latmConfigs[track.PID]
+			medi = &description.Media{
+				Type: description.MediaTypeAudio,
+				Formats: []format.Format{&format.MPEG4AudioLATM{
+					PayloadTyp:      96,
+					CPresent:        false,
+					ProfileLevelID:  30,
+					StreamMuxConfig: streamMuxConfig,
+				}},
+			}
+			clockRate := medi.Formats[0].ClockRate()
+
+			r.OnDataMPEG4AudioLATM(track, func(pts int64, els [][]byte) error {
+				pts = td.Decode(pts)
+
+				pts = multiplyAndDivide(pts, int64(clockRate), 90000)
+
+				for _, el := range els {
+					var elIn mpeg4audio.AudioMuxElement
+					elIn.MuxConfigPresent = true
+					elIn.StreamMuxConfig = streamMuxConfig
+					err := elIn.Unmarshal(el)
+					if err != nil {
+						return err
+					}
+
+					if !reflect.DeepEqual(elIn.StreamMuxConfig, streamMuxConfig) {
+						return fmt.Errorf("dynamic stream mux config is not supported")
+					}
+
+					var elOut mpeg4audio.AudioMuxElement
+					elOut.MuxConfigPresent = false
+					elOut.StreamMuxConfig = streamMuxConfig
+					elOut.Payloads = elIn.Payloads
+					buf, err := elOut.Marshal()
+					if err != nil {
+						return err
+					}
+
+					(*stream).WriteUnit(medi, medi.Formats[0], &unit.MPEG4AudioLATM{
+						Base: unit.Base{
+							NTP: time.Now(),
+							PTS: pts,
+						},
+						Element: buf,
+					})
+
+					pts += mpeg4audio.SamplesPerAccessUnit
+				}
+
+				return nil
+			})
+
 		case *mpegts.CodecMPEG1Audio:
 			medi = &description.Media{
 				Type:    description.MediaTypeAudio,

internal/protocols/mpegts/to_stream_test.go

@@ -7,12 +7,148 @@ import (
 	"testing"
 
 	"github.com/asticode/go-astits"
-	"github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
+	"github.com/bluenviron/gortsplib/v4/pkg/description"
+	"github.com/bluenviron/gortsplib/v4/pkg/format"
+	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4audio"
 	"github.com/bluenviron/mediamtx/internal/logger"
 	"github.com/bluenviron/mediamtx/internal/test"
 	"github.com/stretchr/testify/require"
 )
 
+func TestToStream(t *testing.T) {
+	for _, ca := range []string{
+		"h265",
+		"h264",
+		"mpeg-4 audio latm",
+	} {
+		t.Run(ca, func(t *testing.T) {
+			var buf bytes.Buffer
+			mux := astits.NewMuxer(context.Background(), &buf)
+
+			switch ca {
+			case "h265":
+				err := mux.AddElementaryStream(astits.PMTElementaryStream{
+					ElementaryPID: 122,
+					StreamType:    astits.StreamTypeH265Video,
+				})
+				require.NoError(t, err)
+
+				mux.SetPCRPID(122)
+
+				_, err = mux.WriteTables()
+				require.NoError(t, err)
+
+			case "h264":
+				err := mux.AddElementaryStream(astits.PMTElementaryStream{
+					ElementaryPID: 122,
+					StreamType:    astits.StreamTypeH264Video,
+				})
+				require.NoError(t, err)
+
+				mux.SetPCRPID(122)
+
+				_, err = mux.WriteTables()
+				require.NoError(t, err)
+
+			case "mpeg-4 audio latm":
+				err := mux.AddElementaryStream(astits.PMTElementaryStream{
+					ElementaryPID: 122,
+					StreamType:    astits.StreamTypeAACLATMAudio,
+				})
+				require.NoError(t, err)
+
+				mux.SetPCRPID(122)
+
+				enc1, err := mpeg4audio.AudioMuxElement{
+					MuxConfigPresent: true,
+					StreamMuxConfig: &mpeg4audio.StreamMuxConfig{
+						Programs: []*mpeg4audio.StreamMuxConfigProgram{{
+							Layers: []*mpeg4audio.StreamMuxConfigLayer{{
+								AudioSpecificConfig: &mpeg4audio.AudioSpecificConfig{
+									Type:         2,
+									SampleRate:   48000,
+									ChannelCount: 2,
+								},
+								LatmBufferFullness: 255,
+							}},
+						}},
+					},
+					Payloads: [][][][]byte{{{{1, 2, 3, 4}}}},
+				}.Marshal()
+				require.NoError(t, err)
+
+				enc2, err := mpeg4audio.AudioSyncStream{
+					AudioMuxElements: [][]byte{enc1},
+				}.Marshal()
+				require.NoError(t, err)
+
+				_, err = mux.WriteData(&astits.MuxerData{
+					PID: 122,
+					PES: &astits.PESData{
+						Header: &astits.PESHeader{
+							OptionalHeader: &astits.PESOptionalHeader{
+								MarkerBits:      2,
+								PTSDTSIndicator: astits.PTSDTSIndicatorOnlyPTS,
+								PTS:             &astits.ClockReference{Base: 90000},
+							},
+							StreamID: 192,
+						},
+						Data: enc2,
+					},
+				})
+				require.NoError(t, err)
+			}
+
+			r := &EnhancedReader{R: &buf}
+			err := r.Initialize()
+			require.NoError(t, err)
+
+			desc, err := ToStream(r, nil, nil)
+			require.NoError(t, err)
+
+			switch ca {
+			case "h265":
+				require.Equal(t, []*description.Media{{
+					Type: description.MediaTypeVideo,
+					Formats: []format.Format{&format.H265{
+						PayloadTyp: 96,
+					}},
+				}}, desc)
+
+			case "h264":
+				require.Equal(t, []*description.Media{{
+					Type: description.MediaTypeVideo,
+					Formats: []format.Format{&format.H264{
+						PayloadTyp:        96,
+						PacketizationMode: 1,
+					}},
+				}}, desc)
+
+			case "mpeg-4 audio latm":
+				require.Equal(t, []*description.Media{{
+					Type: description.MediaTypeAudio,
+					Formats: []format.Format{&format.MPEG4AudioLATM{
+						PayloadTyp:     96,
+						ProfileLevelID: 30,
+						StreamMuxConfig: &mpeg4audio.StreamMuxConfig{
+							Programs: []*mpeg4audio.StreamMuxConfigProgram{{
+								Layers: []*mpeg4audio.StreamMuxConfigLayer{{
+									AudioSpecificConfig: &mpeg4audio.AudioSpecificConfig{
+										Type:         2,
+										SampleRate:   48000,
+										ChannelCount: 2,
+									},
+									LatmBufferFullness: 255,
+								}},
+							}},
+						},
+					}},
+				}}, desc)
+			}
+		})
+	}
+}
+
 func TestToStreamNoSupportedCodecs(t *testing.T) {
 	var buf bytes.Buffer
 	mux := astits.NewMuxer(context.Background(), &buf)
@@ -28,7 +164,7 @@ func TestToStreamNoSupportedCodecs(t *testing.T) {
 	_, err = mux.WriteTables()
 	require.NoError(t, err)
 
-	r := &mpegts.Reader{R: &buf}
+	r := &EnhancedReader{R: &buf}
 	err = r.Initialize()
 	require.NoError(t, err)
 
@@ -60,7 +196,7 @@ func TestToStreamSkipUnsupportedTracks(t *testing.T) {
 	_, err = mux.WriteTables()
 	require.NoError(t, err)
 
-	r := &mpegts.Reader{R: &buf}
+	r := &EnhancedReader{R: &buf}
 	err = r.Initialize()
 	require.NoError(t, err)
 

internal/protocols/rtmp/from_stream.go

@@ -137,6 +137,37 @@ func setupAudio(
 		return audioFormatMPEG4Audio
 	}
 
+	var audioFormatMPEG4AudioLATM *format.MPEG4AudioLATM
+	audioMedia = str.Desc.FindFormat(&audioFormatMPEG4AudioLATM)
+
+	if audioMedia != nil && !audioFormatMPEG4AudioLATM.CPresent {
+		str.AddReader(
+			reader,
+			audioMedia,
+			audioFormatMPEG4AudioLATM,
+			func(u unit.Unit) error {
+				tunit := u.(*unit.MPEG4AudioLATM)
+				if tunit.Element == nil {
+					return nil
+				}
+
+				var ame mpeg4audio.AudioMuxElement
+				ame.StreamMuxConfig = audioFormatMPEG4AudioLATM.StreamMuxConfig
+				err := ame.Unmarshal(tunit.Element)
+				if err != nil {
+					return err
+				}
+
+				nconn.SetWriteDeadline(time.Now().Add(writeTimeout))
+				return (*w).WriteMPEG4Audio(
+					timestampToDuration(tunit.PTS, audioFormatMPEG4AudioLATM.ClockRate()),
+					ame.Payloads[0][0][0],
+				)
+			})
+
+		return audioFormatMPEG4AudioLATM
+	}
+
 	var audioFormatMPEG1 *format.MPEG1Audio
 	audioMedia = str.Desc.FindFormat(&audioFormatMPEG1)
 

internal/protocols/rtmp/message/opus_id_header.go

@@ -8,7 +8,7 @@ import (
 var magicSignature = []byte{'O', 'p', 'u', 's', 'H', 'e', 'a', 'd'}
 
 // OpusIDHeader is an Opus identification header.
-// Specification: https://datatracker.ietf.org/doc/html/rfc7845#section-5.1
+// Specification: RFC7845, section 5.1
 type OpusIDHeader struct {
 	Version              uint8
 	ChannelCount         uint8

internal/protocols/rtmp/writer.go

@@ -95,7 +95,7 @@ func (w *Writer) writeTracks() error {
 						case *format.MPEG1Audio:
 							return message.CodecMPEG1Audio
 
-						case *format.MPEG4Audio:
+						case *format.MPEG4Audio, *format.MPEG4AudioLATM:
 							return message.CodecMPEG4Audio
 
 						default:
@@ -133,14 +133,16 @@ func (w *Writer) writeTracks() error {
 		}
 	}
 
-	var audioConfig *mpeg4audio.AudioSpecificConfig
+	var audioConf *mpeg4audio.AudioSpecificConfig
 
 	if track, ok := w.AudioTrack.(*format.MPEG4Audio); ok {
-		audioConfig = track.GetConfig()
+		audioConf = track.Config
+	} else if track, ok := w.AudioTrack.(*format.MPEG4AudioLATM); ok {
+		audioConf = track.StreamMuxConfig.Programs[0].Layers[0].AudioSpecificConfig
 	}
 
-	if audioConfig != nil {
-		enc, err := audioConfig.Marshal()
+	if audioConf != nil {
+		enc, err := audioConf.Marshal()
 		if err != nil {
 			return err
 		}

internal/recorder/format_fmp4.go

@@ -640,10 +640,43 @@ func (f *formatFMP4) initialize() bool {
 					})
 
 			case *rtspformat.MPEG4Audio:
-				co := forma.GetConfig()
-				if co != nil {
+				codec := &mp4.CodecMPEG4Audio{
+					Config: *forma.Config,
+				}
+				track := addTrack(forma, codec)
+
+				f.ri.stream.AddReader(
+					f.ri,
+					media,
+					forma,
+					func(u unit.Unit) error {
+						tunit := u.(*unit.MPEG4Audio)
+						if tunit.AUs == nil {
+							return nil
+						}
+
+						for i, au := range tunit.AUs {
+							pts := tunit.PTS + int64(i)*mpeg4audio.SamplesPerAccessUnit
+
+							err := track.write(&sample{
+								Sample: &fmp4.Sample{
+									Payload: au,
+								},
+								dts: pts,
+								ntp: tunit.NTP.Add(timestampToDuration(pts-tunit.PTS, clockRate)),
+							})
+							if err != nil {
+								return err
+							}
+						}
+
+						return nil
+					})
+
+			case *rtspformat.MPEG4AudioLATM:
+				if !forma.CPresent {
 					codec := &mp4.CodecMPEG4Audio{
-						Config: *co,
+						Config: *forma.StreamMuxConfig.Programs[0].Layers[0].AudioSpecificConfig,
 					}
 					track := addTrack(forma, codec)
 
@@ -652,27 +685,25 @@ func (f *formatFMP4) initialize() bool {
 						media,
 						forma,
 						func(u unit.Unit) error {
-							tunit := u.(*unit.MPEG4Audio)
-							if tunit.AUs == nil {
+							tunit := u.(*unit.MPEG4AudioLATM)
+							if tunit.Element == nil {
 								return nil
 							}
 
-							for i, au := range tunit.AUs {
-								pts := tunit.PTS + int64(i)*mpeg4audio.SamplesPerAccessUnit
-
-								err := track.write(&sample{
-									Sample: &fmp4.Sample{
-										Payload: au,
-									},
-									dts: pts,
-									ntp: tunit.NTP.Add(timestampToDuration(pts-tunit.PTS, clockRate)),
-								})
-								if err != nil {
-									return err
-								}
+							var ame mpeg4audio.AudioMuxElement
+							ame.StreamMuxConfig = forma.StreamMuxConfig
+							err := ame.Unmarshal(tunit.Element)
+							if err != nil {
+								return err
 							}
 
-							return nil
+							return track.write(&sample{
+								Sample: &fmp4.Sample{
+									Payload: ame.Payloads[0][0][0],
+								},
+								dts: tunit.PTS,
+								ntp: tunit.NTP,
+							})
 						})
 				}
 

internal/recorder/format_mpegts.go

@@ -11,6 +11,7 @@ import (
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/ac3"
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/h264"
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/h265"
+	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4audio"
 	"github.com/bluenviron/mediacommon/v2/pkg/codecs/mpeg4video"
 	"github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
 
@@ -306,10 +307,38 @@ func (f *formatMPEGTS) initialize() bool {
 					})
 
 			case *rtspformat.MPEG4Audio:
-				co := forma.GetConfig()
-				if co != nil {
+				track := addTrack(forma, &mpegts.CodecMPEG4Audio{
+					Config: *forma.Config,
+				})
+
+				f.ri.stream.AddReader(
+					f.ri,
+					media,
+					forma,
+					func(u unit.Unit) error {
+						tunit := u.(*unit.MPEG4Audio)
+						if tunit.AUs == nil {
+							return nil
+						}
+
+						return f.write(
+							timestampToDuration(tunit.PTS, clockRate),
+							tunit.NTP,
+							false,
+							true,
+							func() error {
+								return f.mw.WriteMPEG4Audio(
+									track,
+									multiplyAndDivide(tunit.PTS, 90000, int64(clockRate)),
+									tunit.AUs)
+							},
+						)
+					})
+
+			case *rtspformat.MPEG4AudioLATM:
+				if !forma.CPresent {
 					track := addTrack(forma, &mpegts.CodecMPEG4Audio{
-						Config: *co,
+						Config: *forma.StreamMuxConfig.Programs[0].Layers[0].AudioSpecificConfig,
 					})
 
 					f.ri.stream.AddReader(
@@ -317,11 +346,18 @@ func (f *formatMPEGTS) initialize() bool {
 						media,
 						forma,
 						func(u unit.Unit) error {
-							tunit := u.(*unit.MPEG4Audio)
-							if tunit.AUs == nil {
+							tunit := u.(*unit.MPEG4AudioLATM)
+							if tunit.Element == nil {
 								return nil
 							}
 
+							var ame mpeg4audio.AudioMuxElement
+							ame.StreamMuxConfig = forma.StreamMuxConfig
+							err := ame.Unmarshal(tunit.Element)
+							if err != nil {
+								return err
+							}
+
 							return f.write(
 								timestampToDuration(tunit.PTS, clockRate),
 								tunit.NTP,
@@ -331,7 +367,7 @@ func (f *formatMPEGTS) initialize() bool {
 									return f.mw.WriteMPEG4Audio(
 										track,
 										multiplyAndDivide(tunit.PTS, 90000, int64(clockRate)),
-										tunit.AUs)
+										[][]byte{ame.Payloads[0][0][0]})
 								},
 							)
 						})

internal/servers/srt/conn.go

@@ -10,7 +10,6 @@ import (
 	"time"
 
 	"github.com/bluenviron/gortsplib/v4/pkg/description"
-	mcmpegts "github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
 	srt "github.com/datarhei/gosrt"
 	"github.com/google/uuid"
 
@@ -204,7 +203,7 @@ func (c *conn) runPublish(streamID *streamID) error {
 
 func (c *conn) runPublishReader(sconn srt.Conn, path defs.Path) error {
 	sconn.SetReadDeadline(time.Now().Add(time.Duration(c.readTimeout)))
-	r := &mcmpegts.Reader{R: sconn}
+	r := &mpegts.EnhancedReader{R: sconn}
 	err := r.Initialize()
 	if err != nil {
 		return err

internal/staticsources/srt/source.go

@@ -5,7 +5,6 @@ import (
 	"time"
 
 	"github.com/bluenviron/gortsplib/v4/pkg/description"
-	mcmpegts "github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
 	srt "github.com/datarhei/gosrt"
 
 	"github.com/bluenviron/mediamtx/internal/conf"
@@ -70,7 +69,7 @@ func (s *Source) Run(params defs.StaticSourceRunParams) error {
 
 func (s *Source) runReader(sconn srt.Conn) error {
 	sconn.SetReadDeadline(time.Now().Add(time.Duration(s.ReadTimeout)))
-	r := &mcmpegts.Reader{R: sconn}
+	r := &mpegts.EnhancedReader{R: sconn}
 	err := r.Initialize()
 	if err != nil {
 		return err

internal/staticsources/udp/source.go

@@ -9,7 +9,6 @@ import (
 
 	"github.com/bluenviron/gortsplib/v4/pkg/description"
 	"github.com/bluenviron/gortsplib/v4/pkg/multicast"
-	mcmpegts "github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
 
 	"github.com/bluenviron/mediamtx/internal/conf"
 	"github.com/bluenviron/mediamtx/internal/counterdumper"
@@ -137,7 +136,7 @@ func (s *Source) Run(params defs.StaticSourceRunParams) error {
 func (s *Source) runReader(pc net.PacketConn, sourceIP net.IP) error {
 	pc.SetReadDeadline(time.Now().Add(time.Duration(s.ReadTimeout)))
 	pcr := &packetConnReader{pc: pc, sourceIP: sourceIP}
-	r := &mcmpegts.Reader{R: pcr}
+	r := &mpegts.EnhancedReader{R: pcr}
 	err := r.Initialize()
 	if err != nil {
 		return err

internal/unit/mpeg4_audio_latm.go

@@ -0,0 +1,7 @@
+package unit
+
+// MPEG4AudioLATM is a MPEG-4 Audio LATM data unit.
+type MPEG4AudioLATM struct {
+	Base
+	Element []byte
+}