On a Real-Time Walsh-Hadamard/Cosine Transform Image Processor

Abstract

A real-time image processor which is capable of video compression using either the sequency-ordered Walsh-Hadamard transform (WHT)W, or the discrete cosine transform (DCT), is considered. The processing is done on an intraframe basis in (8 X 8) data blocks. The (WHT)W coefficients are computed directly, and then used to obtain the DCT coefficients. This is achieved via an (8 X 8) transformation matrix which is orthonormal, and has a block-diagonal structure. As such, it results in substantial savings in the number of multiplications and additions required to obtain the DCT, relative to its direct computation. Some aspects of a hardware implementation of the processor are also included.