CELP speech coder using novel LPC interpolation and fast codebooksearch method

摘要

An LPC (linear predictive coder) interpolation technique ispresented which is based on interpolating the impulse response of theLPC synthesis filter. After reviewing the basic concept of the CELP(code-excited linear predictive) speech coder, the complexity associatedwith the excitation codebook search is discussed. The author thendescribes the method of interpolating the impulse response of the LPCsynthesis filter. The fast codebook search algorithm for the CELP coderbased on the new interpolation method is described, and experimentalresults with this coder are presented. It is noted that this methodoffers a significant complexity reduction for the codebook search overother typical interpolation schemes. Furthermore, it outperforms otherinterpolation methods at low bit-rates