code: public double distance( NccFeature observed , List<NccFeature> candidates ) {
  
  		double maximum = -Double.MAX_VALUE;
  
  		// The feature which has the best fit will maximize the score
  		for( NccFeature f : candidates ) {
  			double score = DescriptorDistance.ncc(observed, f);
  			if( score > maximum )
  				maximum = score;
  		}
  
  		return 1-0.5*(maximum + 1);
  	}
docs: Computes the best distance to 'observed' from the candidate list.
  @param observed Feature being matched
  @param candidates Set of candidate matches
  @return score from 0 to 1, where lower is closer