public DirectColorModel(int pixelBits, int rmask, int gmask, int bmask, int amask)
public DirectColorModel(int pixelBits, int rmask, int gmask, int bmask)
  public DirectColorModel(int pixelBits,			  int rmask, int gmask, int bmask, int amask)  {    this(ColorSpace.getInstance(ColorSpace.CS_sRGB), pixelBits,	 rmask, gmask, bmask, amask,	 false, // not alpha premultiplied	 Buffers.smallestAppropriateTransferType(pixelBits) // find type	 );  }