1. A systolic array for computing an inverse Discrete Wavelet Transform of a high-frequency sub-band input and a low-frequency sub-band input, said array comprising: an even output generating block, said even output generating block generating even numbered outputs of said output datastream; and an odd output generating block generating odd numbered outputs of said output bitstream; a plurality of processing cells selectively coupled to said high-frequency sub-band input and said low-frequency sub-band input; each processing computing an intermediate output; an adder/controller selectively adding said intermediate outputs from said processing cells; and delay elements selectively coupled to said processing cells, said elements delaying selectively said high frequency sub-band inputs and said low-frequency sub-band inputs to compute the inverse Discrete Wavelet Transform.