An improved wavelet packet threshold function for speech enhancement method

作者：Jia Hairong^*; Ren Yongmei; Zhang Xueying

来源：Journal of Information and Computational Science, 2013, 10(3): 941-948.

• Colored noise
• Flexible adjustment
• Hard function
• Nonlinear functions
• Signaltonoise ratio (SNR)
• SNR
• Speech distortion
• Speech enhancement algorithm
• Speech enhancement methods
• Speech quality
• Threshold functions
• Wavelet Packet
• Wavelet packet coefficient
• Wavelet threshold
• White Gaussian Noise

Speech enhancement method based on the traditional wavelet threshold function had larger distortion and constant deviation. In order to solve the problems, an improved wavelet packet threshold function was presented and used in speech enhancement. In the new method, the nonlinear function was applied to compress the wavelet packet coefficients less than threshold, it ensured that enhanced speech was continuous, and thus removed the distortion. Furthermore, the improved method could change freely hard function into soft function by selecting the different parameters, that flexible adjustment character overcame the flaw of the constant deviation between the true and estimated wavelet packet coefficients, thus enhanced speech quality was modified. Simulation experimental results show that the white Gaussian noise and colored noise are removed largely, the Signal-to-noise Ratio (SNR) of enhanced speech are increased, speech distortion is reduced effectively, compared with the existed speech enhancement algorithms based on wavelet threshold.

• 出版日期2013
• 单位太原理工大学