x264: output headers at start

encoder/libx264/libx264.go

@@ -193,6 +193,10 @@ func NewEncoder(w io.Writer, properties frame.StreamProperties, settings map[str
 		return nil, errors.New("error opening encoder")
 	}
 
+	if err := e.encoderHeaders(); err != nil {
+		return e, err
+	}
+
 	return e, nil
 }
 
@@ -230,6 +234,36 @@ func (e *Encoder) Encode(f frame.Frame) error {
 	return e.encoderEncode(e.pictureIn)
 }
 
+func (e *Encoder) encoderHeaders() error {
+	if e.params.b_repeat_headers > 0 {
+		return nil
+	}
+
+	var nal *C.x264_nal_t
+	var iNal C.int
+	var frameSize C.int
+
+	if frameSize = C.x264_encoder_headers(e.h, &nal, &iNal); frameSize < 0 {
+		return errors.New("error encoding headers")
+	}
+
+	if frameSize == 0 || iNal == 0 {
+		return nil
+	}
+
+	if iNal != 1 {
+		//return errors.New("more than one NAL present")
+	}
+
+	// All NAL payloads are sequential to each other in memory
+	buf := unsafe.Slice((*byte)(nal.p_payload), int(frameSize))
+	if _, err := e.w.Write(buf); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func (e *Encoder) encoderEncode(picture *C.x264_picture_t) error {
 	var nal *C.x264_nal_t
 	var iNal C.int