A METHOD FOR IMPROVING PERFORMANCE OF A VOICE CODER

摘要

A method for improving performance of voice coder comprises the steps of: calculating a target signal for a window; and searching candidate optimal codebooks and candidate optimal codebook gains from the target signal for the window, all codebook indices and all codebook optimal gains. This method further has the steps of: calculating target signals for a second subframe from the targ et signal for the window and candidate optimal codebooks and candidate optimal codebook gains for a first subframe; searching candidate optimal codebooks and candidate optimal codebook gains for the second subframe from the target signal for the second subframe and candidate optimal codebooks and candidate optimal codebook gains for the first subframe; selecting optimal codebook and optimal codebook gain for two subframes respectively from the target signal for the wind ow, candidate optimal gains and all possible quantized gains for the first subframe and candidate optimal codebooks and candidate optimal codebook gains for the second subframe.