Current standard algorithms for storage and transmission of digitized images start with a compression method and ends with a decompression method for recovery of a good replica of the original picture. Unfortunately any recipe leading to significant compression rates involves some loss of information, and as such has to be matched to the nature of the image, and to our tolerance of error. The m...

Zusammenfassung Die Separation unbekannter Signale ist im Bereich der Sprachsignalverarbeitung von besonderer Bedeutung. Die Trennung erfolgt bei Verwendung mehrerer Mikrofone durch Auswertung der resultierenden Laufzeiten zwischen den einzelnen Quellen und Sensoren. Diese Laufzeitdifferenzen führen im Frequenzbereich zu definierten Phasendifferenzen zwischen den Sensorsignalen. Durch die stati...

Accuracy and efficiency are two important issues in designing content-based image retrieval system. In this paper we present an approach on a wavelet transform called tree-structured transform or wavelet packets for texture analysis. A simple texture classification algorithm having excellent performance for dominant channels decomposition tree structured is proposed here. The performance of our...

We consider best m-term approximation in Lp(R) with wave packets generated from a single refinable function. The main examples of such wave packets are orthonormal wavelets or more generally tight wavelet frames based on an MRA (so-called framelets). The approximation classes associated with best m-term approximation in Lp(R) with such wave packets are completely characterized in terms of Besov...

We consider best m-term approximation in Lp(R) with wave packets generated by a single refinable function. The main examples of wave packets are orthonormal wavelets, or more generally wavelet frames based on a multiresolution analysis (so-called framelets). The approximation classes associated with best m-term approximation in Lp(R) for a large class of wave packets are completely characterize...

An important tool for the construction of tight wavelet frames on local fields of positive characteristic with the help of unitary extension principles was presented by Shah and Debnath [Tight wavelet frames on local fields, Analysis, 33 (2013), 293–307]. In this paper, we continue the study based on the extension principles and give an explicit construction of a class of tight framelet packets...

Recently, digital contents are copied easily because of the development of digital technology. So digital watermark technique which aims at copyright protection of digital contents becomes more and more important, and various watermarking methods have been proposed. In this paper, we proposed a method of digital watermark for still image by using wavelet packets, and examine the robustness of t...

Introduction PACT Abstract Wavelet packets represent a generalization of the method of multiresolution decomposition and comprise the entire family of subband coded (tree) decompositions. Wavelet packet best basis selection has become a popular method in image compression, whereas the local discriminant bases algorithm is a relatively new feature extraction method based on a wavelet packet expa...

Speech constitutes much of the communicated information; most other perceived audio signals do not carry nearly as much information. Indeed, much of the non-speech signals maybe classified as ‘noise’ in human communication. The process of separating conversational speech and noise is termed voice activity detection (VAD). This paper describes a new approach to VAD which is based on the Wavelet ...

In this work, a class of multivariate multiwavelet packages with multi-scale are introduced, which are generalizations of multivariant wavelet packages. A method for designing a sort of biorthogonal multiwavelet packages in higher dimensions is presented and their biorthogonality property is characterized by virtue of time-frequency analysis method, matrix theory, and operator theory. Three bio...