anchor.diff:  
   destructor ThtGpImage.Destroy;
   begin
  +  fBitmap.Free;
     GDICheck('ThtGpImage.Destroy', GdipDisposeImage(fHandle));
     if Length(fFilename) > 0 then
       try
  
positive.code: var
    g: ThtGpGraphics;
  begin
    Result := TBitmap.Create;
    Result.Width := GetWidth;
    Result.Height := GetHeight;
    PatBlt(Result.Canvas.Handle, 0, 0, Result.Width, Result.Height, Whiteness);
  
negative.code:     fHandle: GpImage;
      fWidth, fHeight: Cardinal;
      fFilename: string;
      fBitmap: TBitmap;
      function GetHeight: Cardinal;
      function GetWidth: Cardinal;
    public
  