APPARATUS AND METHOD FOR DETERMINING VIDEO ENCODING MOTION COMPENSATION VECTORS

An MPEG-1 or an MPEG-2 motion compensation vector encoder circuit achieves smaller circuit area, and hence lower cost, by using circuitry, including ROMs, designed to implement residue arithmetic to calculate sum squared error in a parallel pipelined fashion. A residue-to-binary converter is implemented using distributed arithmetic and a reduction circuit that removes powers of two times the modulus M, both of which use carry save arithmetic operators. An improved ROM-accumulator, used in the residue-to-binary converter, is implemented using carry-save addition within the ROM-accumulator, and ripple-carry or carry-lookahead addition on the output of the ROM-accumulator.