Besides many advantages of wavelet transform, it has several drawbacks, e.g. ringing, shift variance, aliasing and lack of directionality. Some of them can be eliminated by using wavelet packet transform, stationary wavelet transform, complex wavelet transform, adaptive directional lifting-based wavelet transform, or adaptive wavelet filter banks that use either L2 or L1 norm. This paper contai...

This paper deals with frequency offset estimation in OFDM systems. The proposed approach is based on adapted wavelet packet decomposition of the shifted received signal. The binary tree is optimized, in iterative manner, according to a comparison between decomposed signals energy. The proposed approach is characterized by small number of iterations, short wavelet packet filters and robustness a...

This correspondence introduces a new approach to characterize textures at multiple scales. The performance of wavelet packet spaces are measured in terms of sensitivity and selectivity for the classification of twenty-five natural textures. Both energy and entropy metrics were computed for each wavelet packet and incorporated into distinct scale space representations, where each wavelet packet ...

On the wavelet-packet modulation scheme, wavelet packets are used as carriers, where information to be transmitted is encoded, via an inverse wavelet packet transform, as the coefficient of wavelet packets. The power spectrum density (PSD) of the modulated signals describes the property of modulation in frequency domain, which is discussed by many researchers by simulation. In this paper, the f...

Image fusion is defi ned as the process of combining two or more different images into a new single image retaining important features from each image with extended information content. There are two approaches to image fusion, namely spatial fusion and transform fusion and three levels namely pixel, feature and region level. In spatial fusion, the pixel values from the source images are direct...

In this paper, we propose Wavelet packet transform based prediction of trends in nonlinear financial time series data. Bombay stock Exchange (INDIA) was selected as a tool to show the Wavelet packet transform based prediction of trends in financial time series. The experimental results demonstrate that the proposed method substantially outperform existing approaches.

In this contribution we investigate the error robustness tools offered by the JPEG2000 coding standard. Error robustness is supported on entropy coding level and packet level. A synchronization loss caused by a packet loss can be prevented if marker segments are inserted into the code stream. However, a packet loss and the related loss of wavelet coefficients causes a severe visual distortion. ...

We examine the use of wavelet packets for the fast solution of integral equations with a highly oscillatory kernel. The redundancy of the wavelet packet transform allows the selection of a basis tailored to the problem at hand. It is shown that a well chosen wavelet packet basis is better suited to compress the discretized system than wavelets. The complexity of the matrix–vector product in an ...

In this work an automatic fault classification system is developed for bearing fault classification of three phase induction motor. The system uses the wavelet packet decomposition using ‘db8’ mother wavelet function for feature extraction from the vibration signal, recorded for various bearing fault conditions. The selection of best node of wavelet packet tree is performed by using best tree a...