CODING AND DECODING METHOD FOR VOICE PARAMETERS

摘要

PURPOSE:To efficiently code linear prediction parameters using correlation between frames even when a coding error is generated in a transmission line, the quality deterioration caused by the error only affects the following limited number of frames. CONSTITUTION:Present frame quantized value x(n) is expressed by a weighted sum of past frame output code vectors x(n-1), x(n-2) and x(n-3) and the present frame output code vectors. The present frame output code vector x(n) is determined to make a distortion d minimum where the distortion d is defined between the vector, which is the sum of the past frame output code vector weighted sum and the code vector taken from a code book 4 multiplied by the present frame weight coefficient, and the present frame linear prediction parameters.