diff --git a/MP4/interface.cpp b/MP4/interface.cpp
index f1381cf4..c09f5000 100644
--- a/MP4/interface.cpp
+++ b/MP4/interface.cpp
@@ -114,3 +114,14 @@ void Interface::link( ) {
   moov->AddContent(trak_vide->GetBox(),1);
   moov->AddContent(mvhd->GetBox());
 }
+
+uint32_t Interface::GetContentSize( ) {
+  return ftyp->GetBoxedDataSize( ) + moov->GetBoxedDataSize( );
+}
+
+uint8_t * Interface::GetContents( ) {
+  uint8_t * Result = new uint8_t[GetContentSize( )];
+  memcpy(Result,ftyp->GetBoxedData( ),ftyp->GetBoxedDataSize( ));
+  memcpy(&Result[ftyp->GetBoxedDataSize( )],moov->GetBoxedData( ),moov->GetBoxedDataSize( ));
+  return Result;
+}
diff --git a/MP4/interface.h b/MP4/interface.h
index 5607e8da..0125ddf4 100644
--- a/MP4/interface.h
+++ b/MP4/interface.h
@@ -5,11 +5,13 @@ class Interface {
     Interface();
     ~Interface();
     void link();
+    uint32_t GetContentSize();
+    uint8_t * GetContents();
   private:
+    void UpdateContents();
     Box_ftyp * ftyp;
     Box_moov * moov;
     Box_mvhd * mvhd;
-
     Box_trak * trak_vide;
     Box_tkhd * tkhd_vide;
     Box_mdia * mdia_vide;
@@ -26,7 +28,6 @@ class Interface {
     Box_stco * stco_vide;
     Box_stsd * stsd_vide;
     Box_avcC * avcC_vide;
-
     Box_trak * trak_soun;
     Box_tkhd * tkhd_soun;
     Box_mdia * mdia_soun;