public ProductGrayscaleMeasure(FastGrayscaleMeasure measure1, FastGrayscaleMeasure measure2) {
public ProductGrayscaleMeasure(StagedGrayscaleMeasure measure1, StagedGrayscaleMeasure measure2) {
	public ProductGrayscaleMeasure(FastGrayscaleMeasure measure1, FastGrayscaleMeasure measure2) {		if (measure1 == null)			throw new NullPointerException("measure1 == null");		this.measure1 = measure1;		if (measure2 == null)			throw new NullPointerException("measure2 == null");		this.measure2 = measure2;	}