A continuous differentiable wavelet threshold function for speech enhancement
来源期刊：中南大学学报(英文版)2013年第8期
论文作者：JIA Hai-rong(贾海蓉) ZHANG Xue-ying(张雪英) BAI Jing(白静)
文章页码：2219 - 2225
Key words：continuous differentiable; wavelet threshold function; speech enhancement; Bark wavelet packet; non-fixed deviation; noise
Abstract: Enhanced speech based on the traditional wavelet threshold function had auditory oscillation distortion and the low signal-to-noise ratio (SNR). In order to solve these problems, a new continuous differentiable threshold function for speech enhancement was presented. Firstly, the function adopted narrow threshold areas, preserved the smaller signal speech, and improved the speech quality; secondly, based on the properties of the continuous differentiable and non-fixed deviation, each area function was attained gradually by using the method of mathematical derivation. It ensured that enhanced speech was continuous and smooth; it removed the auditory oscillation distortion; finally, combined with the Bark wavelet packets, it further improved human auditory perception. Experimental results show that the segmental SNR and PESQ (perceptual evaluation of speech quality) of the enhanced speech using this method increase effectively, compared with the existing speech enhancement algorithms based on wavelet threshold.
JIA Hai-rong(贾海蓉), ZHANG Xue-ying(张雪英), BAI Jing(白静)
(College of Information and Engineering, Taiyuan University of Technology, Taiyuan 030024, China)
Abstract:Enhanced speech based on the traditional wavelet threshold function had auditory oscillation distortion and the low signal-to-noise ratio (SNR). In order to solve these problems, a new continuous differentiable threshold function for speech enhancement was presented. Firstly, the function adopted narrow threshold areas, preserved the smaller signal speech, and improved the speech quality; secondly, based on the properties of the continuous differentiable and non-fixed deviation, each area function was attained gradually by using the method of mathematical derivation. It ensured that enhanced speech was continuous and smooth; it removed the auditory oscillation distortion; finally, combined with the Bark wavelet packets, it further improved human auditory perception. Experimental results show that the segmental SNR and PESQ (perceptual evaluation of speech quality) of the enhanced speech using this method increase effectively, compared with the existing speech enhancement algorithms based on wavelet threshold.
Key words:continuous differentiable; wavelet threshold function; speech enhancement; Bark wavelet packet; non-fixed deviation; noise
