Patent ID: 8560329

Claim:
An audio signal compression method in a communications device including a processor, the method comprising: mapping, by the processor, an input audio signal to Pulse Coding Modulation (PCM) domain; multiplying, by the processor, the input audio signal by a window function to obtain a windowed audio signal; calculating, by the processor, an original autocorrelation coefficient of the windowed audio signal, the windowed audio signal having an autocorrelation coefficient correction factor; adjusting, by the processor, the autocorrelation coefficient correction factor in accordance with the original autocorrelation coefficient to obtain an adjusted autocorrelation coefficient correction factor; modifying, by the processor, the original autocorrelation coefficient in accordance with the adjusted autocorrelation coefficient correction factor to obtain a modified autocorrelation coefficient; calculating, by the processor, linear prediction coefficient in accordance with the modified autocorrelation coefficient; coding, by the processor, the input audio signal in accordance with the linear prediction coefficients to obtain an audio coded bit stream, wherein the coding the put audio signal in accordance with the linear prediction coefficients comprises: performing linear prediction for the input signal according to the linear prediction coefficients, calculating a residual signal, coding the residual signal; and outputting, by the processor, the audio coded bit stream.