Patent ID: 6466957
Filing Date: 2002-10-15
Classification: G06F

Abstract:
A wavelet transform filter bank for transforming an input sequence x[n] where n is successive integers to obtain a first output sequence of wavelet coefficients y0[n] and a second output sequence of wavelet coefficients y1[n] from a downsampled input signal x[2n], said wavelet transform filter bank comprising:a. a delay element operationally coupled to said downsampled input signal x[2n] for delaying each successive samples of said downsampled input signal x[2n] to form a delayed downsampled input signal; b. a first transform branch operationally coupled to said downsampled input signal via said delay element said first branch comprising: a plurality of processing elements connected in a serial uniform pattern, said processing elements comprising: i. a unique filter coefficient hN; ii. a multiplier having inputs for receiving said unique filter coefficient hN and said delayed downsampled input signal in said first transform branch and said downsampled input signal in said second transform branch, said multiplier generating a multiplier output; and iii. a series configured summing processing element having parallel delayed output signals and parallel input signals for receiving parallel delayed output signals from an immediately previous processing element for summing with said multiplier output, c. a second transform branch directly operationally coupled to said downsampled input signal, d. wherein the entire computation of said wavelet transform is performed by said first branch and said second branch without redundant computations of terms that comprise said wavelet coefficients, a first portion of said terms being calculated in said first transform branch and a second portion of said terms being calculated in said second transform branch; and e. a coefficient combining portion for selecting terms from said first transform branch and said second transform branch to generate said first output sequence of wavelet coefficients and said second output sequence of wavelet coefficients.