The design of a digital filter for noise reduction in an encoded speech signal

Coding/decoding of noisy speech introduces correlation between speech and noise, which makes the conventional Wiener filter derived from the decoded signal inefficient for noise reduction. This paper proposes a filter design method by using the linear prediction coefficients from the encoded speech data to reduce noise in an encoded speech signal. The proposed design method reduces the correlation between speech and noise, which provides better quality on the enhanced speech signal.