A new method for quantization of the LPC coefficients in a speech coder includes a new weighted error measure including every frame sampling an impulse response from LPC filter (21) of said coder, filtering the samples using a perceptual weighting filter (47) and processing in a computer (39) to calculate autocorrelation function of the weighted impulse response, computing Jacobian matrix for LSF (Line Spectral Frequency), computing correlation of rows of Jacobian matrix and calculating LSF weights by multiplying correlation matrices. <IMAGE>
Quantization of linear prediction coefficients