Wavelet packets

Speech process has benefited a great deal from the wavelet transforms. Wavelet packets decompose signals in to broader components using linear spectral bisecting. In this paper, mixtures of speech signals are decomposed using wavelet packets, the phase difference between the two mixtures are investigated in wavelet domain. In our method Laplacian Mixture Model (LMM) is defined. An Expectation Maximization (EM) algorithm is used for training of the model and calculation of model parameters which is the mixture matrix. And then we compare estimation of mixing matrix by LMM-EM with different wavelet. Therefore individual speech components of speech mixtures are separated.

It is shown that the application of wavelet packet analysis to the feature extraction part of an iris recognition system, is an interesting alternative to Gabor based methods. These methods use iris extraction and unwrapping. Wave atoms is a new transform which is half multi-scale and half multi-directional. This transform offers a better representation of images containing oscillatory patterns and

In this paper we demonstrate the operation of a Wavelet Packet Multi-carrier modulation (WPMCM) based Cognitive Radio (CR) on a multiple-input and multiple-output (MIMO) platform. The wavelet packets are derived from multistage tree-structured paraunitary filter banks. To enable the WPMCM system to co-exist with other licensed users (LU), the WPMCM transmission waveform characteristics are shaped to communicate in the idle time-frequency gaps of the LUs. This is done by vacating WPMCM carriers in and near the region of the LU spectrum. Furthermore, a spectrum estimation unit is tagged to the WPMCM transceiver structure by exploiting the filter bank infrastructure used for Wavelet Packet demodulation. Thus spectrum analysis is done at no additional cost. Through simulation studies the effectiveness of the system is demonstrated.

... [2]. Kalid Sayood 'Introduction to Data Compression' (2nd Ed), Morgan Kaufmann Publishers, 2005.ISBN 81-8147-191-1 [3]. S.Haykin, Communication Systems, (4th Edn) John Wiley & Sons, New York,2001.ISBN 0-471-17869-1 [4]. Shijo M Joseph , Firoz Sha A and Babu Anto ...

ABSTRACT This paper presents a procedure for designing cosine-modulated wavelet filters of arbitrary length applicable to image compression. Both criteria of frequency selectivity and of maximum coding gain are first considered in the design. In order to obtain cosine modulated bases of compactly supported M-band wavelets, additional regularity constraints are then imposed on the filters. The approach presented here allows to derive arbitrary length solutions with high stopband attenuation even in the presence of additional constraints such as regularity. The impact of the different parameters of the wavelet filters on the compression efficiency is evaluated. These filter solutions are also tested comparatively to wavelet packets in a subband coding scheme using lattice vector quantization optimized in the rate-distortion sense

Wavelet transforms and wavelet packets are widely imposed in the analysis and resolution of problems related to science and technical engineering. Decomposition wavelet packet allows several frequency bands according to various levels of resolutions. We apply this transform (PWT) coupled with the SPIHT coder to reduce the limitations of conventional wavelet filter bank. The results obtained using the applied algorithm, are very satisfactory and encouraging compared to many of the best coders cited in the literature and show a visual and numerical superiority over conventional methods. These the promising results are confirmed by visual evaluation parameters (PSNR, MSSIM and VIF).

One of the problems encountered in the field of remote sensing image characterization, is the choice for the right features. The addition of textures as a discriminating parameter is a good help in the step of segmentation of different zones. The authors present an approach that is a mix between a wavelet multiscale analysis and a fractal characterization, in order to exploit both the main characteristic of the two approaches and to override the limitations of the two techniques. The chain was applied to different textured images showing an improvement respect to other methods based on wavelet transform and fractal approach alone

Abstract—The goal of the next generation of core and access op-tical networks is not the only the optical time and frequency signal multiplexing, but also the entire data processing performed in the optical domain, without any electrical-to-optical-to-electrical con-version. In a ...

Wavelet Packet Transform (WPT) provides good spectral and temporal resolutions in arbitrary regions of the time-frequency plane. This flexible choice of the time-frequency tiling benefits most of the applications where the standard Wavelet Transform (WT) has already shown ...

This paper introduces a new implementation of wavelet packet decomposition which is combined with SPIHT (Set Partitioning in Hierarchical Trees) compression scheme. We provide the analysis of the problems arising from the application of zerotree quantisation ...

Based on a signal model and a discussion on to what extent a good bearing monitoring method should trust it, we present several analysis tools for bearing condition monitoring and conclude that wavelets are especially well suited for this task. Then we describe a large-scale ...

In order to satisfy the needs of new multimedia applications, the problem of content-based video coding has to be addressed. A new approach of object interior coding is proposed. It is based on an arbitrarily-shaped subband transform followed by a generalized embedded zerotree wavelet algorithm. It is shown that the proposed technique achieves good compression results and has additional properties such as being computationally efficient, keeping the same dimensionality in the transformed domain, being perfect ...