Phase linearization of filters in analysis/synthesis filter banks

Abstract

Analysis/synthesis filter banks with perfect reconstruction property have attracted much attention. In some applications, particularly image coding, it is desirable to design filter banks in which the filters have linear phase. We present a method of linearizing the passband phase response of filters in any given filter bank. While linearizing the phase response, this method preserves the magnitude response of the filters, the perfect reconstruction property, and the paraunitary property (orthonormality). We present the eigen-approach design and the anticausal implementation of this technique. Using this technique, we illustrate the importance of linear phase in subband coding. >