Patent ID: 7499854
Filing Date: 2009-03-03
Classification: G10L

Abstract:
1. A code excited linear prediction speech coder, comprising: an adaptive codebook configured to generate an adaptive codevector; a random codebook configured to generate a random codevector; a linear predictive coefficients coder configured to generate quantized linear predictive coefficients by performing coding of a target vector by multi-stage vector quantization; a linear predictive coefficients decoder configured to generate linear predictive coefficients by decoding said quantized linear predictive coefficients, and a synthesis filter configured to receive a signal based on said adaptive codevector and said random codevector, and to perform linear prediction coefficients synthesis on said signal by using said linear predictive coefficients, and to generate a synthetic speech signal by the synthesis filter being excited by the adaptive codevector and the random codevector, said linear predictive coefficients coder comprising: wherein, the scalar is determined, by learning, using the equation: where C1N(i) is decoded codevector A, C2m codevector A is the first codevector, codevector B is the second codevector, N is code for codevector A, EN is coded distortion when the code for codevector A is N, aN is amplitude corresponding to the code for codevector A, t is time when the code for codevector A is N, Y i is vector order, and I is vector length.