Efficient implementation of perceptual postfilter for CELP coding of speech

摘要

An efficient method to implement the perceptual posterfilter for the suppression of coding noise in CELP-coded speech is proposed. The method is based on approximating the response of an all-pole filter to the response of the pole-zero form postfilter via cepstrum processing. This all-pole postfilter can then be implemented more efficiently than the pole-zero postfilter with less computation and filter memory.