DESIGN OF UNEQUAL−LENGTH LINEAR−PHASE FILTER BANKS WITHOUT REDUNDANCY (WedAmPO2)

In this paper, we present a new structure for linear−phase filter banks without redundancy, which have unequal−length filters at each subband. First, we extend the simplified lattice structure of the linear−phase filter bank to the unequal−length linear−phase paraunitary filter bank. In general, the unequal−length linear−phase paraunitary filter bank has equal−length filters at both the analysis and the synthesis bank because the synthesis bank is a transposed version of the analysis one, while the biorthogonal one does not. So, we discuss the conditions that the linear−phase biorthogonal filter bank has unequal−length filters at 1) the analysis bank, 2) the synthesis bank, and 3) both the analysis and the synthesis banks. Finally, several design and image coding examples are shown.