Files
monibuca/plugin/mp4/pkg/track.go
T
langhuihui f4923d9df6 in progress
2025-02-11 20:21:37 +08:00

432 lines
12 KiB
Go

package mp4
import (
"io"
"slices"
. "m7s.live/v5/plugin/mp4/pkg/box"
)
type (
Track struct {
Cid MP4_CODEC_TYPE
TrackId uint32
SampleTable
Duration uint32
Height uint32
Width uint32
SampleRate uint32
SampleSize uint16
SampleCount uint32
ChannelCount uint8
Timescale uint32
// StartDts uint64
// EndDts uint64
// StartPts uint64
// EndPts uint64
Samplelist []Sample
ELST *EditListBox
ExtraData []byte
writer io.WriteSeeker
fragments []Fragment
defaultSize uint32
defaultDuration uint32
// defaultSampleFlags uint32
// baseDataOffset uint64
// stbl []byte
FragmentSequenceNumber uint32
//for subsample
// defaultIsProtected uint8
// defaultPerSampleIVSize uint8
// defaultCryptByteBlock uint8
// defaultSkipByteBlock uint8
// defaultConstantIV []byte
// defaultKID [16]byte
// lastSeig *SeigSampleGroupEntry
// lastSaiz *SaizBox
// subSamples []SencEntry
}
Fragment struct {
Offset uint64
Duration uint32
FirstDts uint64
FirstPts uint64
LastPts uint64
LastDts uint64
}
)
func (track *Track) makeElstBox() *EditListBox {
delay := track.Samplelist[0].PTS * 1000 / uint64(track.Timescale)
entryCount := 1
version := byte(0)
boxSize := 12
entrySize := 12
if delay > 0xFFFFFFFF {
version = 1
entrySize = 20
}
// if delay > 0 {
// entryCount += 1
// }
boxSize += 4 + entrySize*entryCount
entrys := make([]ELSTEntry, entryCount)
// if entryCount > 1 {
// elst.entrys.entrys[0].segmentDuration = startCt
// elst.entrys.entrys[0].mediaTime = -1
// elst.entrys.entrys[0].mediaRateInteger = 0x0001
// elst.entrys.entrys[0].mediaRateFraction = 0
// }
//简单起见,mediaTime先固定为0,即不延迟播放
entrys[entryCount-1].SegmentDuration = uint64(track.Duration)
entrys[entryCount-1].MediaTime = 0
entrys[entryCount-1].MediaRateInteger = 0x0001
entrys[entryCount-1].MediaRateFraction = 0
return CreateEditListBox(version, entrys)
}
func (track *Track) Seek(dts uint64) int {
for i, sample := range track.Samplelist {
if sample.DTS*1000/uint64(track.Timescale) < dts {
continue
} else if track.Cid.IsVideo() {
if sample.KeyFrame {
return i
}
} else {
return i
}
}
return -1
}
func (track *Track) makeEdtsBox() *ContainerBox {
return CreateContainerBox(TypeEDTS, track.makeElstBox())
}
func (track *Track) AddSampleEntry(entry Sample) {
if len(track.Samplelist) <= 1 {
track.Duration = 0
} else {
delta := int64(entry.DTS - track.Samplelist[len(track.Samplelist)-1].DTS)
if delta < 0 {
track.Duration += 1
} else {
track.Duration += uint32(delta)
}
}
track.Samplelist = append(track.Samplelist, entry)
}
func (track *Track) makeTkhdBox() *TrackHeaderBox {
tkhd := CreateTrackHeaderBox(track.TrackId, uint64(track.Duration), track.Width, track.Height)
tkhd.Duration = uint64(track.Duration)
tkhd.TrackID = track.TrackId
if track.Cid == MP4_CODEC_AAC || track.Cid == MP4_CODEC_G711A || track.Cid == MP4_CODEC_G711U || track.Cid == MP4_CODEC_OPUS {
tkhd.Volume = 0x0100
} else {
tkhd.Width = track.Width << 16
tkhd.Height = track.Height << 16
}
return tkhd
}
func (track *Track) makeMinfBox() *ContainerBox {
var mhdbox IBox
switch track.Cid {
case MP4_CODEC_H264, MP4_CODEC_H265:
mhdbox = CreateVideoMediaHeaderBox()
case MP4_CODEC_G711A, MP4_CODEC_G711U, MP4_CODEC_AAC,
MP4_CODEC_MP2, MP4_CODEC_MP3, MP4_CODEC_OPUS:
mhdbox = CreateSoundMediaHeaderBox()
default:
panic("unsupport codec id")
}
dinfbox := CreateDataInformationBox()
stblbox := track.makeStblBox()
return CreateContainerBox(TypeMINF, mhdbox, dinfbox, stblbox)
}
func (track *Track) makeMdiaBox() *ContainerBox {
mdhdbox := CreateMediaHeaderBox(track.Timescale, uint64(track.Duration))
hdlrbox := MakeHdlrBox(GetHandlerType(track.Cid))
minfbox := track.makeMinfBox()
return CreateContainerBox(TypeMDIA, mdhdbox, hdlrbox, minfbox)
}
func (track *Track) makeStblBox() IBox {
track.STSD = track.makeStsd(GetHandlerType(track.Cid))
if track.Cid == MP4_CODEC_H264 || track.Cid == MP4_CODEC_H265 {
track.STSS = track.makeStssBox()
}
return CreateContainerBox(TypeSTBL, track.STSD, track.STSS, track.STTS, track.CTTS, track.STSC, track.STSZ, track.STCO)
}
func (track *Track) makeStsd(handler_type HandlerType) *STSDBox {
var avbox IBox
if track.Cid == MP4_CODEC_H264 {
avbox = CreateDataBox(TypeAVCC, track.ExtraData)
} else if track.Cid == MP4_CODEC_H265 {
avbox = CreateDataBox(TypeHVCC, track.ExtraData)
} else if track.Cid == MP4_CODEC_AAC || track.Cid == MP4_CODEC_MP2 || track.Cid == MP4_CODEC_MP3 {
avbox = CreateESDSBox(uint16(track.TrackId), track.Cid, track.ExtraData)
} else if track.Cid == MP4_CODEC_OPUS {
avbox = CreateOpusSpecificBox(track.ExtraData)
}
var entry IBox
if handler_type == TypeVIDE {
entry = CreateVisualSampleEntry(GetCodecNameWithCodecId(track.Cid), uint16(track.Width), uint16(track.Height), avbox)
} else if handler_type == TypeSOUN {
entry = CreateAudioSampleEntry(GetCodecNameWithCodecId(track.Cid), uint16(track.ChannelCount), uint16(track.SampleSize), track.SampleRate, avbox)
}
return CreateSTSDBox(entry)
}
// fmp4
func (track *Track) makeTraf() *TrackFragmentBox {
// Create tfhd box
tfhd := track.makeTfhdBox()
// Create tfdt box
tfdt := track.makeTfdtBox()
// Create trun box with all samples
trun := track.makeTrunBox(0, len(track.Samplelist))
// Create track fragment box with all necessary boxes
traf := CreateTrackFragmentBox(tfhd, tfdt, trun)
return traf
}
func (track *Track) makeTfhdBox() *TrackFragmentHeaderBox {
tfFlags := uint32(0)
tfFlags |= TF_FLAG_DEFAULT_BASE_IS_MOOF
tfFlags |= TF_FLAG_SAMPLE_DESCRIPTION_INDEX_PRESENT
tfFlags |= TF_FLAG_DEFAULT_SAMPLE_DURATION_PRESENT
tfFlags |= TF_FLAG_DEFAULT_SAMPLE_SIZE_PRESENT
tfFlags |= TF_FLAG_DEFAULT_SAMPLE_FLAGS_PRESENT
tfhd := CreateTrackFragmentHeaderBox(track.TrackId, tfFlags)
// Calculate default sample duration
if len(track.Samplelist) > 1 {
var totalDuration uint64 = 0
var count int = 0
for i := 1; i < len(track.Samplelist); i++ {
duration := track.Samplelist[i].DTS - track.Samplelist[i-1].DTS
if duration > 0 {
totalDuration += duration
count++
}
}
if count > 0 {
tfhd.DefaultSampleDuration = uint32(totalDuration / uint64(count))
}
}
// Set default sample size
if len(track.Samplelist) > 0 {
tfhd.DefaultSampleSize = uint32(track.Samplelist[0].Size)
}
// Set default sample flags
if track.Cid.IsVideo() {
tfhd.DefaultSampleFlags = MOV_FRAG_SAMPLE_FLAG_DEPENDS_YES | MOV_FRAG_SAMPLE_FLAG_IS_NON_SYNC
} else {
tfhd.DefaultSampleFlags = MOV_FRAG_SAMPLE_FLAG_DEPENDS_NO
}
return tfhd
}
func (track *Track) makeTfdtBox() *TrackFragmentBaseMediaDecodeTimeBox {
return CreateTrackFragmentBaseMediaDecodeTimeBox(uint64(track.Samplelist[0].DTS))
}
func (track *Track) makeStssBox() *STSSBox {
var stss []uint32
for i, sample := range track.Samplelist {
if sample.KeyFrame {
stss = append(stss, uint32(i+1))
}
}
return CreateSTSSBox(stss)
}
func (track *Track) makeTfraBox() *TrackFragmentRandomAccessBox {
return CreateTrackFragmentRandomAccessBox(track.TrackId, slices.Collect(func(yield func(TFRAEntry) bool) {
for _, f := range track.fragments {
if !yield(TFRAEntry{
Time: f.FirstPts,
MoofOffset: f.Offset,
}) {
break
}
}
}))
}
func (track *Track) makeTrunBox(start, end int) *TrackRunBox {
// Set flags in the correct order
flag := TR_FLAG_DATA_OFFSET
// Then set sample duration flag (0x000100)
flag |= TR_FLAG_DATA_SAMPLE_DURATION
// Then set sample size flag (0x000200)
flag |= TR_FLAG_DATA_SAMPLE_SIZE
// Then set sample flags if needed (0x000400)
if track.Cid.IsVideo() {
flag |= TR_FLAG_DATA_SAMPLE_FLAGS
}
// Create a new TrackRunBox
// Finally set composition time offset flag if needed (0x000800)
for i := start; i < end; i++ {
if track.Samplelist[i].PTS != track.Samplelist[i].DTS {
flag |= TR_FLAG_DATA_SAMPLE_COMPOSITION_TIME
break
}
}
trun := CreateTrackRunBox(flag, uint32(end-start))
// Fill entry list
trun.Entries = make([]TrunEntry, trun.SampleCount)
for i := 0; i < int(trun.SampleCount); i++ {
sample := &track.Samplelist[start+i]
// Duration
if i < int(trun.SampleCount)-1 {
trun.Entries[i].SampleDuration = uint32(track.Samplelist[start+i+1].DTS - sample.DTS)
} else {
trun.Entries[i].SampleDuration = trun.Entries[i-1].SampleDuration
}
// Size
trun.Entries[i].SampleSize = uint32(sample.Size)
// Flags
if flag&TR_FLAG_DATA_SAMPLE_FLAGS != 0 {
if sample.KeyFrame {
trun.Entries[i].SampleFlags = MOV_FRAG_SAMPLE_FLAG_DEPENDS_NO | MOV_FRAG_SAMPLE_FLAG_IS_SYNC
} else {
trun.Entries[i].SampleFlags = MOV_FRAG_SAMPLE_FLAG_DEPENDS_YES | MOV_FRAG_SAMPLE_FLAG_IS_NON_SYNC
}
}
// Composition time offset
if flag&TR_FLAG_DATA_SAMPLE_COMPOSITION_TIME != 0 {
trun.Entries[i].SampleCompositionTimeOffset = int32(sample.PTS - sample.DTS)
}
}
return trun
}
func (track *Track) makeStblTable() {
sameSize := true
movchunks := make([]movchunk, 0)
ckn := uint32(0)
var stts []STTSEntry
var ctts []CTTSEntry
var stco []uint64
for i, sample := range track.Samplelist {
sttsEntry := STTSEntry{SampleCount: 1, SampleDelta: 1}
cttsEntry := CTTSEntry{SampleCount: 1, SampleOffset: uint32(sample.PTS) - uint32(sample.DTS)}
if i == len(track.Samplelist)-1 {
stts = append(stts, sttsEntry)
} else {
var delta uint64 = 1
if track.Samplelist[i+1].PTS >= sample.PTS {
delta = track.Samplelist[i+1].PTS - sample.PTS
}
if len(stts) > 0 && delta == uint64(stts[len(stts)-1].SampleDelta) {
stts[len(stts)-1].SampleCount++
} else {
sttsEntry.SampleDelta = uint32(delta)
stts = append(stts, sttsEntry)
}
}
if len(ctts) == 0 {
ctts = append(ctts, cttsEntry)
} else {
if ctts[len(ctts)-1].SampleOffset == cttsEntry.SampleOffset {
ctts[len(ctts)-1].SampleCount++
} else {
ctts = append(ctts, cttsEntry)
}
}
if sameSize && i < len(track.Samplelist)-1 && track.Samplelist[i+1].Size != track.Samplelist[i].Size {
sameSize = false
}
if i > 0 && sample.Offset == track.Samplelist[i-1].Offset+int64(track.Samplelist[i-1].Size) {
movchunks[ckn-1].samplenum++
} else {
ck := movchunk{chunknum: ckn, samplenum: 1, chunkoffset: uint64(sample.Offset)}
movchunks = append(movchunks, ck)
stco = append(stco, uint64(sample.Offset))
ckn++
}
}
var sampleSize uint32
var entrySizelist []uint32
if sameSize {
sampleSize = uint32(track.Samplelist[0].Size)
} else {
entrySizelist = make([]uint32, len(track.Samplelist))
for i := 0; i < len(track.Samplelist); i++ {
entrySizelist[i] = uint32(track.Samplelist[i].Size)
}
}
var stsc []STSCEntry
for i, chunk := range movchunks {
if i == 0 || chunk.samplenum != movchunks[i-1].samplenum {
stsc = append(stsc, STSCEntry{FirstChunk: chunk.chunknum + 1, SampleDescriptionIndex: 1, SamplesPerChunk: chunk.samplenum})
}
}
if track.Cid == MP4_CODEC_H264 || track.Cid == MP4_CODEC_H265 {
track.CTTS = CreateCTTSBox(ctts)
}
track.STTS = CreateSTTSBox(stts)
track.STSC = CreateSTSCBox(stsc)
track.STCO = CreateSTCOBox(stco)
track.STSZ = CreateSTSZBox(sampleSize, entrySizelist)
}
// func (track *Track) makeSidxBox(totalSidxSize uint32, refsize uint32) []byte {
// sidx := NewSegmentIndexBox()
// sidx.ReferenceID = track.TrackId
// sidx.TimeScale = track.Timescale
// sidx.EarliestPresentationTime = track.StartPts
// sidx.ReferenceCount = 1
// sidx.FirstOffset = 52 + uint64(totalSidxSize)
// entry := SidxEntry{
// ReferenceType: 0,
// ReferencedSize: refsize,
// SubsegmentDuration: 0,
// StartsWithSAP: 1,
// SAPType: 0,
// SAPDeltaTime: 0,
// }
// if len(track.Samplelist) > 0 {
// entry.SubsegmentDuration = uint32(track.Samplelist[len(track.Samplelist)-1].DTS) - uint32(track.StartDts)
// }
// sidx.Entrys = append(sidx.Entrys, entry)
// sidx.Box.Box.Size = sidx.Size()
// _, boxData := sidx.Encode()
// return boxData
// }