Image correspondences using cross-correlation

Finding corresponding features in a pair of images is the basis of many optic flow, stereo vision and image registration algorithms. One straightforward approach to finding a match is to take a small patch of one image, compute its sliding cross-correlation with the other image, and find a peak. This submission supplies a class which implements this method.There are many other ways of finding correspondences, but normalised cross-correlation is relatively easy to understand, and fairly effective if a sparse set of matches is sufficient and the change in viewpoint is not too large. Th