OPTONEURAL SYSTEM FOR INVARIANT PATTERN-RECOGNITION

An optoneural system is developed for invariant pattern recognition. T he system consists of an optical correlator and a neural network. The correlator uses Fourier-Mellin spatial filters (FMF) for feature extra ction. The FMF yields an unique output pattern for an input object. Th e present method works only with one object present in the input scene . The optical features extracted from the output pattern are shift, sc ale, and rotation invariant and are used as input to the neural networ k. The neural network is a multilayer feedforward net with back-propag ation learning rule. Because of substantial reduction of the dimension of feature vectors provided by optical FMF. the small neural network is simply simulated in a personal computer. Optical experimental resul ts are shown.