Check out correlation filters - there's a ton out there - OTSDF, MMCF, MOSSE, ZACFs, etc. They're basically designed do template matching but in such a way that the input statistics are considered to refine the output result for better matching (less errors, improved separation between classes, etc). I don't know of any Java libraries, but here is a MATLAB library of different types (https://github.com/vboddeti/CorrelationFilters) and here is a very basic implementation of OTSDF using C++ via the Eigen library (https://github.com/jsmereka/PatchBasedCorrelation/tree/maste...).