An improved wavelet-based speech enhancement method using adaptive block thresholding

An improved wavelet-based speech enhancement method using adaptive block thresholding is proposed. Adaptive block thresholding is introduced by G. Yu to eliminate the musical noise artifacts, but the performance for unvoiced speech is not satisfactory. To solve this problem, a voiced/unvoiced decision is applied and a small block size is set for unvoiced speech. Furthermore, the thresholding is adjusted considering both the intrascale and interscale dependencies of wavelet coefficients. The experimental results show that the improved method can obtain better denoising performance than the method proposed by G. Yu, especially for unvoiced speech.