private BitmapPalette CreateMonoPalette()
{
       List<System.Windows.Media.Color> colors = new List<System.Windows.Media.Color>();
       for (byte i = 0; i <= 255; i++)
       {
            colors.Add(new System.Windows.Media.Color {
                 A = 255,
                 B = i,
                 R = i,
                 G = i
            });
       }

       return new BitmapPalette(colors);
}