Recent studies suggest that multicarrier systems using wavelets outperform conventional OFDM systems using the FFT, in that they have well-contained side lobes, improved spectral efficiency and BER performance, and they do not require a cyclic prefix. Here we study the wavelet packet and discrete wavelet transforms, comparing the BER performance of wavelet transform-based multicarrier systems a...

Image watermarking has proven to be quite an efficient tool for the purpose of copyright protection and authentication over the last few years. In this paper, a novel image watermarking technique in the wavelet domain is suggested and tested. To achieve more security and robustness, the proposed techniques relies on using two nested watermarks that are embedded into the image to be watermarked....

1. The unit sphere in R and the classification of regular solids 1 2. Symmetries of platonic solids 3 3. Basic representation theory of finite groups 6 4. Haar basis of L(R) 17 5. Haar multiresolution of L(R) 20 6. Daubechies wavelets 22 7. Wavelets and group representations 24 8. Numerical integration on the sphere 25 9. Unique factorization domains and Hilbert’s Nulstellensatz 27 10. Spherica...

We explore the stability of image reconstruction algorithms under deterministic compressed sensing. Recently, we have proposed [1-3] deterministic compressed sensing algorithms for 2D images. These algorithms are suitable when Daubechies wavelets are used as the sparsifying basis. In the initial work, we have shown that the algorithms perform well for images with sparse wavelets coefficients. I...

In this paper a genetic-based enhancement of digital image watermarking in the Discrete Wavelet Transform domain is presented. The proposed method is based on adaptive synthesis of a mother wavelet used for image decomposition. Wavelet synthesis is performed using parametrization based on an orthogonal lattice structure. A genetic algorithm is applied as an optimization method to synthesize a w...

In certain classes of dynamical systems invariant sets with a strange geometry appear. For example the iteration of two-dimensional quasi-periodically forced skew product, under certain conditions, gives us strange non-chaotic attractors. To obtain analytical approximation of these objects it seems more natural to use wavelets instead of the more usual Fourier approach. The aim of the talk is t...

In this paper a new method for adaptive synthesis of a smooth orthogonal wavelet, using fast neural network and genetic algorithm, is introduced. Orthogonal lattice structure is presented. A new method of supervised training of fast neural network is introduced to synthesize a wavelet with desired energy distribution between output signals from low–pass and high–pass filters on subsequent level...

Computer aided liver image analysis is of profound interest in recent years due to their faster, accurate and reliable characteristics. Qualitative methods include contrast stretching, smoothness, brightness, sharpness etc. Quantitative analysis, on the other hand make use of geometrical measurements such as area, perimeter, diagonal length, horizontal and vertical width etc. These methods of a...

Modern spectral and harmonic analysis is based on Fourier transforms. However, these techniques are less efficient in tracking the signal dynamics for transient disturbances in power system engineering. Consequently, the wavelet transform has been introduced as an adaptable technique for non-stationary signal analysis. Although the application of wavelets in the area of power system engineering...