Harmonic analysis studies the representation of functions as the linear combination of basic wave-like functions. It plays a fundamental role in the processing of time-series signals and images. Recent years have witnessed many efforts to adapt the Fourier and wavelet analysis to the domain of 3D shapes. The manifold Fourier analysis relies on the eigenfunctions of the Laplace-Beltrami operator...

Traditional video coders use the previous frame to perform motion estimation and compensation. Though they are less complex and have minimum coding delays, these coders lose their efficiency when subjected to scalability requirements. Recent 3D wavelet coders using lifting schemes offer high compression efficiency and scalability without significant loss in performance. The main drawback of 3D ...

The intrinsically hierarchical and blended structure of interstellar molecular clouds, plus the always increasing resolution of astronomical instruments, demand advanced and automated pattern recognition techniques for identifying and connecting source components in spectroscopic cubes. We extend the work done in multiresolution analysis using Wavelets for astronomical 2D images to 3D spectrosc...

In this paper a novel method for the efficient search and retrieval of 3D objects is presented. Firstly, the 3D PacketWavelet Transform is used to extract low-level descriptor vectors, which characterize geometrically a 3D object. Secondly, knowledge, in the sense of weight vectors, is formed and assigned to the low-level descriptor vectors. These two types of information are then combined and ...

In a virtual sculpture project, we would like to sculpt in real-time 3D objects sampled in volume elements (voxels). The drawback of this kind of representation is that a very huge number of voxels is required to represent large and detailed objects. Consequently, the memory cost will be very large and the user/object interaction will be slowed down. We proposed a multiresolution representation...

This paper aims at studying the characterization of Dirac-structure edges with wavelet transform, and selecting the suitable wavelet functions to detect them. Three significant characteristics of the local maximum modulus of the wavelet transform with respect to the Dirac-structure edges are presented: (1) slope invariant: the local maximum modulus of the wavelet transform of a Dirac-structure ...

Magnetic resonance (MR) images are normally corrupted by random noise which makes the automatic feature extraction and analysis of clinical data complicated. Hence there is a necessity to denoise MR images for better analysis. Therefore, several denoising methods have been applied to improve MR image quality. Disadvantage of previous methods are reconstruction process is complicated and time co...

This paper concerns the issue of wavelet analysis of signals by continuous and discrete wavelet transforms (CWT – Continous Wavelet Transform, DWT – Discrete Wavelet Transform). The main goal of our work was to develop a program which, through the CWT and the DWT analyses, would obtain graph of time-scale changes and would transform it into the spectrum, that is a graph of frequency changes. In...

This paper presents new image descriptors based on color, texture, shape, and wavelets for object and scene image classification. First, a new three Dimensional Local Binary Patterns (3D-LBP) descriptor, which produces three new color images, is proposed for encoding both color and texture information of an image. The 3D-LBP images together with the original color image then undergo the Haar wa...

We describe the Wavelets Around Land Masses (WAVAL) system for the embedded coding of 3D oceanographic images. These images differ from those arising in other applications in that valid data exists only at grid points corresponding to sea; grids points that cover land or lie beyond the bathymetry have no associated data. For these images, the WAVAL system employs a 3D lifting wavelet transform ...