대한음성학회지:말소리 (MALSORI)
- 제60호
- /
- Pages.181-190
- /
- 2006
- /
- 1226-1173(pISSN)
MMSE Estimator 기반의 적응 콤 필터링을 이용한 잡음 제거
Noise Reduction Using MMSE Estimator-based Adaptive Comb Filtering
- Park, Jeong-Sik (KAIST) ;
- Oh, Yung-Hwan (KAIST)
- 발행 : 2006.12.30
초록
This paper describes a speech enhancement scheme that leads to significant improvements in recognition performance when used in the ASR front-end. The proposed approach is based on adaptive comb filtering and an MMSE-related parameter estimator. While adaptive comb filtering reduces noise components remarkably, it is rarely effective in reducing non-stationary noises. Furthermore, due to the uniformly distributed frequency response of the comb-filter, it can cause serious distortion to clean speech signals. This paper proposes an improved comb-filter that adjusts its spectral magnitude to the original speech, based on the speech absence probability and the gain modification function. In addition, we introduce the modified comb filtering-based speech enhancement scheme for ASR in mobile environments. Evaluation experiments carried out using the Aurora 2 database demonstrate that the proposed method outperforms conventional adaptive comb filtering techniques in both clean and noisy environments.
키워드