Add support FLAC codec to MP4/MSE

pkg/iso/atoms.go

@@ -32,6 +32,16 @@ const (
 	Mdat                        = "mdat"
 )
 
+const (
+	sampleIsNonSync  = 0x10000
+	sampleDependsOn1 = 0x1000000
+	sampleDependsOn2 = 0x2000000
+
+	SampleVideoIFrame    = sampleDependsOn2
+	SampleVideoNonIFrame = sampleDependsOn1 | sampleIsNonSync
+	SampleAudio          = sampleIsNonSync
+)
+
 func (m *Movie) WriteFileType() {
 	m.StartAtom(Ftyp)
 	m.WriteString("iso5")
@@ -250,7 +260,7 @@ func (m *Movie) WriteAudioTrack(id uint32, codec string, timescale uint32, chann
 	m.EndAtom() // TRAK
 }
 
-func (m *Movie) WriteMovieFragment(seq, tid, duration, size uint32, time uint64) {
+func (m *Movie) WriteMovieFragment(seq, tid, duration, size, flags uint32, time uint64) {
 	m.StartAtom(Moof)
 
 	m.StartAtom(MoofMfhd)
@@ -276,10 +286,10 @@ func (m *Movie) WriteMovieFragment(seq, tid, duration, size uint32, time uint64)
 			TfhdDefaultSampleFlags |
 			TfhdDefaultBaseIsMoof,
 	)
-	m.WriteUint32(tid)       // track id
-	m.WriteUint32(duration)  // default sample duration
-	m.WriteUint32(size)      // default sample size
-	m.WriteUint32(0x2000000) // default sample flags
+	m.WriteUint32(tid)      // track id
+	m.WriteUint32(duration) // default sample duration
+	m.WriteUint32(size)     // default sample size
+	m.WriteUint32(flags)    // default sample flags
 	m.EndAtom()
 
 	m.StartAtom(MoofTrafTfdt)
@@ -314,5 +324,4 @@ func (m *Movie) WriteData(b []byte) {
 	m.StartAtom(Mdat)
 	m.Write(b)
 	m.EndAtom()
-
 }

pkg/iso/codecs.go

@@ -2,6 +2,7 @@ package iso
 
 import (
 	"github.com/AlexxIT/go2rtc/pkg/core"
+	"github.com/AlexxIT/go2rtc/pkg/pcm"
 )
 
 func (m *Movie) WriteVideo(codec string, width, height uint16, conf []byte) {
@@ -46,9 +47,11 @@ func (m *Movie) WriteVideo(codec string, width, height uint16, conf []byte) {
 func (m *Movie) WriteAudio(codec string, channels uint16, sampleRate uint32, conf []byte) {
 	switch codec {
 	case core.CodecAAC, core.CodecMP3:
-		m.StartAtom("mp4a")
+		m.StartAtom("mp4a") // supported in all players and browsers
+	case core.CodecFLAC:
+		m.StartAtom("fLaC") // supported in all players and browsers
 	case core.CodecOpus:
-		m.StartAtom("Opus")
+		m.StartAtom("Opus") // supported in Chrome and Firefox
 	case core.CodecPCMU:
 		m.StartAtom("ulaw")
 	case core.CodecPCMA:
@@ -56,6 +59,11 @@ func (m *Movie) WriteAudio(codec string, channels uint16, sampleRate uint32, con
 	default:
 		panic("unsupported iso audio: " + codec)
 	}
+
+	if channels == 0 {
+		channels = 1
+	}
+
 	m.Skip(6)
 	m.WriteUint16(1)                    // data_reference_index
 	m.Skip(2)                           // version
@@ -72,6 +80,10 @@ func (m *Movie) WriteAudio(codec string, channels uint16, sampleRate uint32, con
 		m.WriteEsdsAAC(conf)
 	case core.CodecMP3:
 		m.WriteEsdsMP3()
+	case core.CodecFLAC:
+		m.StartAtom("dfLa")
+		m.Write(pcm.FLACHeader(false, sampleRate))
+		m.EndAtom()
 	case core.CodecOpus:
 		// don't know what means this magic
 		m.StartAtom("dOps")