Patent ID: 6687668
Filing Date: 2004-02-03
Classification: G10L

Abstract:
A method of searching an MP-MLQ (Multi Pulse Maximum Likelihood Quantization) fixed codebook through predetermination of a grid bit for predicting the positions of pulses during high bit rate decoding of voice signals in a CELP (Code Excited Linear Prediction) vocoder, which reduces process time of G.723.1, the method comprising the steps of:generating a target vector divided into odd order and even order pulses; determining an amplitude of the target vector; generating composite sound by using the target vector; comparing the composite sound with an original sound without DC; determining a grid bit by the comparison; checking whether the grid bit is zero; searching the even order pulses when the grid bit is zero; checking whether the grid bit is one (1); searching the odd order pulses when the grid bit is one (1); and searching all of the even and odd order pulses when the grid bit is not zero or one.