Performance of mixed-metric optimized ternary correlation filters on realistic binary and gray-scale imagery
David L. Flannery, William E. Phillips, Dennis H. Goldstein · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1993
The ternary phase-amplitude filter (TPAF) is by definition restricted to the modulation values -1, 0, and 1, thus comprising a binary phase-only filter (BPOF) multiplied by a binary- amplitude pattern, i.e., a region of support. The TPAF offers an attractive combination of real-time implementation with available devices and good correlation performance. Smart (optimized distortion-invariant) TPAF formulations have been developed. The TPAF enables filter implementation with magneto-optic devices and these devices also can be used for image input if gray scale scenes can be binarized while preserving good correlation performance. We provide simulation results addressing the comparative performance of mixed-metric smart TPAF's using gray scale, edge-enhanced and binary images derived from identical original scenes. The variation of filter performance with training set background intensity level is examined.