Apparatus and method for encoding speech using a codebook excited linear predictive (CELP) speech processor and an algebraic codebook for use therewith. The CELP speech processor receives a digital speech input representative of human speech and performs linear predictive code analysis and perceptual weighting filtering to produce a short term speech information and a long term speech information. The CELP speech processor utilizes an organized, non-overlapping, algebraic codebook containing a predetermined number of vectors, uniformly distributed over a multi-dimensional sphere to generate a remaining speech residual. The short term speech information, long term speech information and remaining speech residual are combinable to form a quality reproduction of the digital speech input.
U.S. Patent and Trademark Office DescriptionPTO
Inventor(s) John S. Baras
, Yuhung Kao