APPLICATIONS OF COMPLEX-VALUED WAVELET TRANSFORMS TO SUBBAND DECOMPOSITION

A method for constructing complex valued linear phase FIR conjugate qu adrature filters and associated wavelet bases is described. Each filte r is derived by replacing certain zeros of a real valued FIR conjugate quadrature filter by their reciprocal conjugates. The derived filters have the same frequency response magnitudes as the original filters a nd their liner phase property permits the use of symmetrization in sub band decomposition to avoid border discontinuities that result from si gnal periodization. Subband decomposition and reconstruction using bot h a length 6 filter associated with a Daubechies wavelet bases and a r elated length 6 complex valued linear phase filter are compared to ill ustrate the reduced border effects.