Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Speech Enhancement with Natural Sounding Residual Noise Based on Connected Time-Frequency Speech Presence Regions | EURASIP Journal on Applied Signal Processing 2005 18 2954-2964 2005 K. V. S0rensen and S. V. Andersen Speech Enhancement with Natural Sounding Residual Noise Based on Connected Time-Frequency Speech Presence Regions Karsten Vandborg Sorensen Department of Communication Technology Aalborg University DK-9220 Aalborg East Denmark Email kvs@ Soren Vang Andersen Department of Communication Technology Aalborg University DK-9220 Aalborg East Denmark Email sva@ Received 13 May 2004 Revised 3 March 2005 We propose time-frequency domain methods for noise estimation and speech enhancement. A speech presence detection method is used to find connected time-frequency regions of speech presence. These regions are used by a noise estimation method and both the speech presence decisions and the noise estimate are used in the speech enhancement method. Different attenuation rules are applied to regions with and without speech presence to achieve enhanced speech with natural sounding attenuated background noise. The proposed speech enhancement method has a computational complexity which makes it feasible for application in hearing aids. An informal listening test shows that the proposed speech enhancement method has significantly higher mean opinion scores than minimum mean-square error log-spectral amplitude MMSE-LSA and decision-directed MMSE-LSA. Keywords and phrases speech enhancement noise estimation minimum statistics speech presence detection. 1. INTRODUCTION The performance of many speech enhancement methods relies mainly on the quality of a noise power spectral density PSD estimate. When the noise estimate differs from the true noise it will lead to artifacts in the enhanced speech. The approach taken in this paper is based on connected region speech presence detection. Our aim is to exploit spectral and temporal masking mechanisms in the human auditory system 1 to reduce the perception of these artifacts in speech presence regions and eliminate the .
