Optical pattern recognition and classification are commonly implemented by
means of correlation, and a specialized filter for the patterns to be recog
nized must be constructed first. Although it has the inherent advantages of
high speed, shift invariance, and high distinguishability, how to build an
effective and easily implemented filter or group of filters still remains
an open problem. By combining the methods of correlation filtering, transfo
rm encoding, and neural network mapping, a least substructuring elements (L
SE) extracting method is proposed in this paper. Some basic substructuring
elements of a specific group of patterns to be processed could be extracted
to compose masks in the least number. Computer simulation upon the 26 Engl
ish capital letters is provided. One integrated hybrid optoelectronic imple
mentation system is described, (C) 1999 Society of Photo-Optical Instrument
ation Engineers. [S0091-3286(99)00710-2].