FatBear: a nonarithmetic pico filter
Harold G. Longbotham, Mike Johnson, J.J. Harris, Redouan Rouzky · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1993
This paper is but a first step toward a fast, robust, nonarithmetic filtering theory. The following will assume the sampled sequence is from a finite TOS (totally ordered set) S so that any subset (window) of sequence values may be ordered. In addition we will assume the existence of a distance function (metric) on S. This distance function may be as simple as counting but all results presented hold for any TOS with any distance function. In addition a median type operator will be defined that always has as output an element in S, unlike the usual median operator. Implementations will be discussed. It will be shown that implementation involves only a two layer NAND/NOR for ordering and range estimations, and the assumption of counting. Operation counts will be discussed.