/// <summary>
        /// Creates a new PixelData array.
        /// </summary>
        /// <param name="frame"></param>
        public void Update(ReplayDepthImageFrame frame)
        {
            PixelData = new short[frame.PixelDataLength];
              frame.CopyPixelDataTo(PixelData);

              if (depthFrame32 == null) {
            depthFrame32 = new byte[frame.Width * frame.Height * 4];
              }

              if (Bitmap == null) {
            Bitmap = new WriteableBitmap(frame.Width, frame.Height, 96, 96, PixelFormats.Bgra32, null);
              }

              ConvertDepthFrame(PixelData);

              int stride = Bitmap.PixelWidth * Bitmap.Format.BitsPerPixel / 8;
              Int32Rect dirtyRect = new Int32Rect(0, 0, Bitmap.PixelWidth, Bitmap.PixelHeight);
              Bitmap.WritePixels(dirtyRect, depthFrame32, stride, 0);

              RaisePropertyChanged(() => Bitmap);
        }
 /// <summary>
 /// Updates the depth frame pixel data. Each pixel contains both the player and the depth
 /// information.
 /// </summary>
 /// <param name="frame"></param>
 public void UpdatePixelData(ReplayDepthImageFrame frame)
 {
     if (DepthPixelData == null)
     DepthPixelData = new short[frame.PixelDataLength];
       frame.CopyPixelDataTo(DepthPixelData);
 }