public PartGrayscaleMeasure(FastGrayscaleMeasureFactory factory) {
public PartGrayscaleMeasure(StagedGrayscaleMeasureFactory factory) {
	public PartGrayscaleMeasure(FastGrayscaleMeasureFactory factory) {		if (factory == null)			throw new NullPointerException("factory == null");		this.factory = factory;	}