On Hilbert-pairs from non-minimum phase Daubechies filters

A Hilbert-Pair is a pair of wavelets that are Hilbert transforms of each other. Previously an interesting discovery about the celebrated family of orthonormal Daubechies filters was made. It is found that if two filters whose lengths differ by four are chosen from this family, a Hilbert-Pair of reasonable approximation quality is obtained. The previous work considered only minimum phase filters. Extensions to the non-minimum phase case is considered here and a technique is presented for constructing non-minimum phase Hilbert-pairs.