Quadrature prefilters for the discrete wavelet transform

Discrepancies between the discrete wavelet transform and the coefficients of the wavelet series are known to be reducible by initialization of input data. Prefilters based on Lagrange interpolants are derived here for biorthogonal compact support wavelet systems, providing exact subspace projection in cases of local polynomial smoothness. The resulting convergence acceleration in a nonpolynomial test case is examined. Irregular sampling rates are also accommodated.