This paper presents a novel wavelet-based image denoising algorithm under overcomplete expansion. In order to optimize the denoising performance, we make a systematic study of both signal and noise characteristics under overcomplete expansion. Highband coefficients are viewed as the mixture of non-edge class and edge class observing different probability models. Based on improved statistical mo...

In this paper we propose a speech enhancement method based on using the wavelets theory and the envelope expansion technique. The proposed method does not require an explicit estimation of the noise level or of the a priori knowledge of the SNR, which is usually needed in most of enhancement methods. Performance of the proposed method was evaluated on speech recorded in real conditions and with...