code: protected double computeScore( int leftX , int rightX , int centerY ) {
  
  		double ret=0;
  
  		for( int y = -radiusY; y <= radiusY; y++ ) {
  			for( int x = -radiusX; x <= radiusX; x++ ) {
  				double l = GeneralizedImageOps.get(imageLeft,leftX+x,centerY+y);
  				double r = GeneralizedImageOps.get(imageRight,rightX+x,centerY+y);
  
  				ret += Math.abs(l-r);
  			}
  		}
  
  		return ret;
  	}
docs: Compute SAD (Sum of Absolute Difference) error.
  
  @param leftX X-axis center left image
  @param rightX X-axis center left image
  @param centerY Y-axis center for both images
  @return Fit score for both regions.