METHOD OF AND DEVICE FOR SPEECH SIGNAL CODING AND DECODING BY VECTOR QUANTIZATION TECHNIQUES

摘要

A speech coding and decoding technique involves filtering of blocks of digital samples of speech signals to be coded by a linear prediction inverse filter, whose coefficients are chosen out of a code book of quantized filter coefficient vectors, obtaining a residual signal subdivided into vectors. The weighted mean square error arising from quantizing these vectors with quantized residual vectors contained in a code book and forming excitation waveforms is computed. The coded signal for each block of samples consists of the coefficient vector index chosen for the inverse filter as well as of the indices of the vectors of the excitation waveforms which generate the minimum weighted mean square error. During decoding a similarly coded signal provides the coefficient for a synthesis filter, and quantized residual vectors to excite it.