2025-03-14 12:21:51 +05:00

143 lines
2.9 KiB
Go

package converter
import (
"bufio"
"os"
"sync"
"github.com/bluenviron/gortsplib/v4/pkg/format"
"github.com/bluenviron/mediacommon/v2/pkg/codecs/h264"
"github.com/bluenviron/mediacommon/v2/pkg/formats/mpegts"
)
func multiplyAndDivide(v, m, d int64) int64 {
secs := v / d
dec := v % d
return (secs*m + dec*m/d)
}
// MpegtsMuxer allows to save a H264 / MPEG-4 audio stream into a MPEG-TS file.
type MpegtsMuxer struct {
FileName string
H264Format *format.H264
Mpeg4AudioFormat *format.MPEG4Audio
f *os.File
b *bufio.Writer
w *mpegts.Writer
h264Track *mpegts.Track
// mpeg4AudioTrack *mpegts.Track
dtsExtractor *h264.DTSExtractor
mutex sync.Mutex
}
// Initialize initializes a MpegtsMuxer.
func (e *MpegtsMuxer) Initialize() error {
var err error
e.f, err = os.Create(e.FileName)
if err != nil {
return err
}
e.b = bufio.NewWriter(e.f)
e.h264Track = &mpegts.Track{
Codec: &mpegts.CodecH264{},
}
//e.mpeg4AudioTrack = &mpegts.Track{
// Codec: &mpegts.CodecMPEG4Audio{
// // Config: *e.mpeg4AudioFormat.Config,
// },
//}
e.w = mpegts.NewWriter(e.b, []*mpegts.Track{e.h264Track}) // add e.mpeg4AudioTrack
return nil
}
// Close closes all the MpegtsMuxer resources.
func (e *MpegtsMuxer) Close() {
err := e.b.Flush()
if err != nil {
panic(err)
}
err = e.f.Close()
if err != nil {
panic(err)
}
}
// WriteH264 writes a H264 access unit into MPEG-TS.
func (e *MpegtsMuxer) WriteH264(au [][]byte, pts int64) error {
e.mutex.Lock()
defer e.mutex.Unlock()
var filteredAU [][]byte
nonIDRPresent := false
idrPresent := false
for _, nalu := range au {
if len(nalu) != 0 {
typ := h264.NALUType(nalu[0] & 0x1F)
switch typ {
case h264.NALUTypeSPS:
e.H264Format.SPS = nalu
continue
case h264.NALUTypePPS:
e.H264Format.PPS = nalu
continue
case h264.NALUTypeAccessUnitDelimiter:
continue
case h264.NALUTypeIDR:
idrPresent = true
case h264.NALUTypeNonIDR:
nonIDRPresent = true
}
filteredAU = append(filteredAU, nalu)
}
}
au = filteredAU
if au == nil || (!nonIDRPresent && !idrPresent) {
return nil
}
// Add SPS and PPS before access unit that contains an IDR.
if idrPresent {
au = append([][]byte{e.H264Format.SPS, e.H264Format.PPS}, au...)
}
if e.dtsExtractor == nil {
// Skip samples silently until we find one with an IDR.
if !idrPresent {
return nil
}
e.dtsExtractor = h264.NewDTSExtractor()
}
dts, err := e.dtsExtractor.Extract(au, pts)
if err != nil {
return err
}
// Encode into MPEG-TS.
return e.w.WriteH264(e.h264Track, pts, dts, au)
}
// writeMPEG4Audio writes MPEG-4 audio access units into MPEG-TS.
//func (e *MpegtsMuxer) writeMPEG4Audio(aus [][]byte, pts int64) error {
// e.mutex.Lock()
// defer e.mutex.Unlock()
//
// return e.w.WriteMPEG4Audio(
// e.mpeg4AudioTrack, multiplyAndDivide(pts, 90000, int64(e.Mpeg4AudioFormat.ClockRate())), aus)
//}