rename 'read' into 'play', 'publish' into 'record' (#463)

examples/client-play-format-h265-save-to-disk/mpegts_muxer.go

@@ -0,0 +1,123 @@
+package main
+
+import (
+	"bufio"
+	"os"
+	"time"
+
+	"github.com/bluenviron/mediacommon/pkg/codecs/h265"
+	"github.com/bluenviron/mediacommon/pkg/formats/mpegts"
+)
+
+func durationGoToMPEGTS(v time.Duration) int64 {
+	return int64(v.Seconds() * 90000)
+}
+
+// mpegtsMuxer allows to save a H265 stream into a MPEG-TS file.
+type mpegtsMuxer struct {
+	vps []byte
+	sps []byte
+	pps []byte
+
+	f            *os.File
+	b            *bufio.Writer
+	w            *mpegts.Writer
+	track        *mpegts.Track
+	dtsExtractor *h265.DTSExtractor
+}
+
+// newMPEGTSMuxer allocates a mpegtsMuxer.
+func newMPEGTSMuxer(vps []byte, sps []byte, pps []byte) (*mpegtsMuxer, error) {
+	f, err := os.Create("mystream.ts")
+	if err != nil {
+		return nil, err
+	}
+	b := bufio.NewWriter(f)
+
+	track := &mpegts.Track{
+		Codec: &mpegts.CodecH265{},
+	}
+
+	w := mpegts.NewWriter(b, []*mpegts.Track{track})
+
+	return &mpegtsMuxer{
+		vps:   vps,
+		sps:   sps,
+		pps:   pps,
+		f:     f,
+		b:     b,
+		w:     w,
+		track: track,
+	}, nil
+}
+
+// close closes all the mpegtsMuxer resources.
+func (e *mpegtsMuxer) close() {
+	e.b.Flush()
+	e.f.Close()
+}
+
+// encode encodes a H265 access unit into MPEG-TS.
+func (e *mpegtsMuxer) encode(au [][]byte, pts time.Duration) error {
+	// prepend an AUD. This is required by some players
+	filteredAU := [][]byte{
+		{byte(h265.NALUType_AUD_NUT) << 1, 1, 0x50},
+	}
+
+	isRandomAccess := false
+
+	for _, nalu := range au {
+		typ := h265.NALUType((nalu[0] >> 1) & 0b111111)
+		switch typ {
+		case h265.NALUType_VPS_NUT:
+			e.vps = nalu
+			continue
+
+		case h265.NALUType_SPS_NUT:
+			e.sps = nalu
+			continue
+
+		case h265.NALUType_PPS_NUT:
+			e.pps = nalu
+			continue
+
+		case h265.NALUType_AUD_NUT:
+			continue
+
+		case h265.NALUType_IDR_W_RADL, h265.NALUType_IDR_N_LP, h265.NALUType_CRA_NUT:
+			isRandomAccess = true
+		}
+
+		filteredAU = append(filteredAU, nalu)
+	}
+
+	au = filteredAU
+
+	if len(au) <= 1 {
+		return nil
+	}
+
+	// add VPS, SPS and PPS before random access access unit
+	if isRandomAccess {
+		au = append([][]byte{e.vps, e.sps, e.pps}, au...)
+	}
+
+	var dts time.Duration
+
+	if e.dtsExtractor == nil {
+		// skip samples silently until we find one with a IDR
+		if !isRandomAccess {
+			return nil
+		}
+		e.dtsExtractor = h265.NewDTSExtractor()
+	}
+
+	var err error
+	dts, err = e.dtsExtractor.Extract(au, pts)
+	if err != nil {
+		return err
+	}
+
+	// encode into MPEG-TS
+	return e.w.WriteH26x(e.track, durationGoToMPEGTS(pts), durationGoToMPEGTS(dts), isRandomAccess, au)
+}