internal override ImageData PrepareImageData()
        {
            ImagePrivateDataBitmap data      = (ImagePrivateDataBitmap)Data;
            ImageDataBitmap        imageData = new ImageDataBitmap(_document);

            //imageData.Data = data.Data;
            //imageData.Length = data.Length;

            data.CopyBitmap(imageData);

            return(imageData);
        }