diff --git a/format/raw/muxer.go b/format/raw/muxer.go
index d70cea4..107d790 100644
--- a/format/raw/muxer.go
+++ b/format/raw/muxer.go
@@ -2,7 +2,7 @@ package raw
 
 import (
 	"bytes"
-	"io"
+	"os"
 
 	"github.com/deepch/vdk/codec/h265parser"
 
@@ -15,13 +15,28 @@ var startCode = []byte{0, 0, 0, 1}
 
 type Muxer struct {
 	idx int8
-	w   io.WriteSeeker
+	w   *os.File
 }
 
-func NewMuxer(v io.WriteSeeker) *Muxer {
-	return &Muxer{w: v}
+func NewMuxer(filePatch, fileName string) (*Muxer, error) {
+
+	if _, err := os.Stat(filePatch); os.IsNotExist(err) {
+		err := os.MkdirAll(filePatch, os.ModePerm)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	f2, err := os.Create(filePatch + fileName)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Muxer{w: f2}, nil
 }
+
 func (element *Muxer) WriteHeader(streams []av.CodecData) (err error) {
+
 	for i, stream := range streams {
 		switch stream.Type() {
 		case av.H264:
@@ -32,9 +47,13 @@ func (element *Muxer) WriteHeader(streams []av.CodecData) (err error) {
 			element.idx = int8(i)
 		}
 	}
+
 	return
+
 }
-func (element *Muxer) WritePacket(pkt *av.Packet) (err error) {
+
+func (element *Muxer) WriteAvPacket(pkt *av.Packet) (err error) {
+
 	if pkt.Idx == element.idx {
 		_, err = element.w.Write(startCode)
 		if err != nil {
@@ -42,5 +61,19 @@ func (element *Muxer) WritePacket(pkt *av.Packet) (err error) {
 		}
 		_, err = element.w.Write(pkt.Data[4:])
 	}
+
 	return
+
+}
+
+func (element *Muxer) WriteRTPPacket(pkt *[]byte) (err error) {
+
+	return
+
+}
+
+func (element *Muxer) Close() error {
+
+	return element.w.Close()
+
 }