Adds keyframe API

pkg/mp4/muxer.go

@@ -0,0 +1,37 @@
+package mp4
+
+import (
+	"github.com/deepch/vdk/av"
+	"github.com/deepch/vdk/codec/h264parser"
+	"github.com/deepch/vdk/format/mp4"
+	"time"
+)
+
+func MarshalMP4(sps, pps, frame []byte) []byte {
+	writer := &MemoryWriter{}
+	muxer := mp4.NewMuxer(writer)
+
+	stream, err := h264parser.NewCodecDataFromSPSAndPPS(sps, pps)
+	if err != nil {
+		panic(err)
+	}
+
+	if err = muxer.WriteHeader([]av.CodecData{stream}); err != nil {
+		panic(err)
+	}
+
+	pkt := av.Packet{
+		CompositionTime: time.Millisecond,
+		IsKeyFrame:      true,
+		Duration:        time.Second,
+		Data:            frame,
+	}
+	if err = muxer.WritePacket(pkt); err != nil {
+		panic(err)
+	}
+	if err = muxer.WriteTrailer(); err != nil {
+		panic(err)
+	}
+
+	return writer.buf
+}