Patent ID: 9716901
Date: 2017-07-25
CPC Classifications: G10L,H04N

Claim:
1. A method for reducing quantization error of an audio signal using a pre-filter and a post-filter, the method comprising: obtaining, by a processor of a computing device configured to distinguish between signal-correlated and signal-uncorrelated components of quantization error in audio signals, a quantization error of an audio signal, the audio signal having a given rate; separating, by the processor, the quantization error into a signal-correlated component and a signal-uncorrelated component, wherein the quantization error is based on a distortion measure; assigning, by the processor, a first penalty amount to the signal-correlated component of the quantization error by using the pre-filter prior to quantization of the audio signal; assigning, by the processor, a second penalty amount to the signal-uncorrelated component of the quantization error by using the post-filter after quantization of the audio signal, the first penalty amount being different than the second penalty amount; and reducing the signal-uncorrelated component of the quantization error for the given rate by adjusting, by the processor, the second penalty assigned to the signal-uncorrelated component to an amount greater than the first penalty assigned to the signal-correlated component.