Processing arbitrary-length signals with linear-phase cosine-modulated filter banks

This paper presents methods for the decomposition of arbitrary-length signals with linear-phase cosine-modulated "lter banks. The analysis "lters of this "lter bank are divided into two sets having di!erent centers of symmetry. This prohibits the use of standard extension methods as described in the literature. Nevertheless, we show that symmetric extension can be adapted in such a way that the "lter bank is support-preservative. Methods for dealing with arbitrary length of both signals and "lters are presented. Finally, applications in image and audio coding are outlined. In audio coding the proposed processing methods allow to e$ciently avoid pre-echoes. ( 2000 Elsevier Science B.V. All rights