Patent ID: 6889185
Filing Date: 2005-05-03
Classification: G10L

Abstract:
1. In a coder including an LPC filter and a translator for translating LPC coefficients to LSF coefficients, an LSF quantizer comprising: a codebook responsive to an LSF target vector for quantizing said LSF target vector; means for searching within said codebook for determining codebook entry that results in quantized output that best matches LSF target vector using LSF weights computed from perceptual-weighting input response to the LPC filter; means for applying said LSF target vector to said codebook to provide a quantized output; said searching means including means for applying an impulse to said LPC filter; means for running samples of said LPC response; a perceptual filter for filtering said samples; and means for calculating autocorrelation function by weighted response, Jacobian matrix for said LSF vectors, correlation of rows of Jacobian matrix, and LSF weights by multiplying correlation matrices.