This paper addresses the problem of enhancing a speech signal corrupted by interfering signals. A new noise reduction algorithm based on a logarithmic microphone array and the multiresolution wavelet transform is described. The proposed processing is applied in the time-spectral domain with respect to the logarithmic subband decomposition of the spectrum of each microphone signal. The advantage...

A new voice conversion method that improves the quality of the voice conversion output at higher sampling rates is proposed. Speaker Transformation Algorithm Using Segmental Codebooks (STASC) is modified to process source and target speech spectra in different subbands. The new method ensures better conversion at sampling rates above 16KHz. Discrete Wavelet Transform (DWT) is employed for subba...

In this paper we present a new method for voice disorders classification based on a gammachirp wavelet transform and multilayer neural network (MNN). The processing algorithm is based on a hybrid technique which uses the gammachirp wavelets coefficients as input of the MNN. The training step uses a speech database of several pathological and normal voices collected from the national hospital “R...

in this paper a wavelet-based logo watermarking scheme is presented. the logo watermark is embedded into all sub-blocks of the lln sub-band of the transformed host image, using quantization technique. extracted logos from all sub-blocks are merged to make the extracted watermark from distorted watermarked image. knowing the quantization step-size, dimensions of logo and the level of wavelet tra...

electrocardiogram (ecg) is one of the most common biological signals which plays a significant role in diagnosis of heart diseases. one of the most important parts of ecg signal processing is interpretation of qrs complex and obtaining its characteristics. r wave is one of the most important sections of this complex which has an essential role in diagnosis of heart rhythm irregularities and als...

this paper presents a rational haar wavelet operational method for solving the inverse laplace transform problemand improves inherent errors from irrational haar wavelet. the approach is thus straightforward, rather simple andsuitable for computer programming. we define that $p$ is the operational matrix for integration of the orthogonalhaar wavelet. simultaneously, simplify the formulaes of li...

introduction: evoked potentials arisen by stimulating the brain can be utilized as a communication tool  between humans and machines. most brain-computer interface (bci) systems use the p300 component,  which is an evoked potential. in this paper, we evaluate the use of the hidden markov model (hmm) for  detection of p300.  materials and methods: the wavelet transforms, wavelet-enhanced indepen...

This paper proposes a new wavelet-based algorithm for voice/unvoiced classification of speech segments. The classification process is based on: 1) statistical analysis of the energy-frequency distribution of the speech signal using wavelet transform, and 2) estimation of the short-time zero-crossing rate of the signal. First, the ratio of the average energy in the low-frequency wavelet subbands...

abstract background: a computer aided diagnosis system was established using the wavelet transform and neural network to differentiate malignant from benign in a   group of patients with histo-pathologically proved breast lesions based on the data derived independ­ently from time-intensity profile.   materials and methods: the per­formance of the artificial neural network (ann) was evaluated us...