Iva Bogdanova Vandergheynst

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We propose here some basic approaches to direct processing of the

360^o

-images as we take into consideration the geometry of each one. Obviously, the geometry of each of these images is a consequence of the geometry of the sensor's mirror used. This technical report is organized as follows: In the first section we develop the Laplacian operator on non-Euclidean manifolds. First we start by derivation of Laplacian operator on Riemannian manifolds and than we derive it explicitly for each of the non-Euclide

This dissertation investigates wavelets as a multiscale tool on non-Euclidean manifolds. The growing importance of using non-Euclidean manifolds as a geometric model for data comes from the diversity of the data collected. In this work we mostly deal with ...

The specific issue addressed in this paper is tailoring specific functionality to allow a group of teachers and students to carry out the learning process in Digital Signal and Image Processing in an electronic virtual environment that is meant to replace the physical class environment. In order such an environment to be performed, not only the course content itself but also different Web-based tools for interaction between the students and teachers are needed. A Graphical User Interface (GUI), designed and

This paper presents a novel method for classification of multilead electrocardiogram (ECG) signals. The feature extraction is based on the random projection (RP) concept for dimensionality reduction. Furthermore, the classification is performed by a neuro- ...

In this paper we present a computational model of dynamic visual attention on the sphere which combines static (intensity,chromaticity, orientation) and motion features in order to detect salient locations in omnidirectional image sequences while working d ...

We review the known construction of the continuous wavelet transform (CWT) on the two-sphere. Next we describe the construction of a CWT on the upper sheet of a two- sheeted hyperboloid, emphasizing the similarities between the two cases. Finally we give s ...

This paper presents a novel method for classification of multi-lead electrocardiogram (ECG) signals. The feature extraction is based on the random projection (RP) concept for dimensionality reduction. Furthermore, the classification is performed by a neuro ...

In this paper we exploit the Continuous Wavelet Transform (CWT) on the two dimensional sphere, introduced previously by two of us, to build associated Discrete Wavelet Frames. We first explore half-continuous frames, i.e., frames where the position remains ...

This paper presents a novel local motion estimation algorithm for omnidirectional images. The algorithm captures correlation between two spherical images of a scene, taken from arbitrary viewpoints, with the objective to reduce the encoding rate of these images. It first performs a multiresolution decomposition of the spherical images, in order to improve the consistency of the motion estimation, with a limited computational complexity. Then, it determines pairs of similar solid angles and matches blocks of

A SIFT algorithm in spherical coordinates for omnidirectional images is proposed. This algorithm can generate two types of local descriptors, Local Spherical Descriptors and Local Planar Descriptors. With the first ones, point matching between two omnidire ...

The Internet offers new and exciting possibilities for personalized and distance education. The Web Teaching project at ITS is creating the tools needed to provide complete high quality multimedia courses for delivery over the World Wide Web (WWW). Aside from the flexibility that Web-based education provides, the exploitation of ITS s experience in the area of image and signal processing offers the potential to fundamentally change the teaching process. This paper presents a system designed to perform multi

In this technical report the Discrete Wavelet Frames are build on the already existing Spherical Continuous Wavelet Transform. The spherical half-continuous frames are explored, i.e when the position on the sphere is kept continuous variable. Then, the controlled frames are introduced, which comes from the particular nature of the underlying theory, namely the conflict between dilation and the compacity of the spherical manifold. The perspectives for the future work are given.

We build wavelets on the 2-Hyperboloid. First, we define dilations on the hyperboloid through conic projection. Then, incorporating hyperbolic motions belonging to

SO_0(1,2)

, we define a family of hyperbolic wavelets. The continuous wavelet transform (CWT)is obtained by convolution of the scaled wavelets with the signal. This wavelet transform is proved to be invertible whenever wavelets satisfy a particular admissibility condition. Finally, the Euclidean limit of this CWT on the hyperboloid is considered

In this paper the Continuous Wavelet Transform on the sphere is exploited to build the asociated Discrete Wavelet Frames. First, the half-continuous frames, i.e. frames where the position remains a continuous variable, is presented and then the fully discrete theory is presented. The notion of controlled frames is introduced, which reflects the particular nature of the underlying theory, particularly the apperant conflict between dilation and the compacity of the sphere. The paper is concluded with some num

In this paper we build a Continuous Wavelet Transform (CWT) on the upper sheet of the 2-hyperboloid

H_+^2

. First, we define a class of suitable dilations on the hyperboloid through conic projection. Then, incorporating hyperbolic motions belonging to $SO ...

A new generation of optical devices that generate images covering a larger part of the field of view than conventional cameras, namely catadioptric cameras, is slowly emerging. These omnidirectional images will most probably deeply impact computer vision i ...

Iva Bogdanova Vandergheynst

Chattez avec Graph Search

Laplacian Operator, Diffusion Flow and Active Contour on non-Euclidean Images

Wavelets on non-Euclidean manifolds

Virtual classroom for multimedia teaching on WWW

A Multi-Lead ECG Classification Based on Random Projection Features

Dynamic Visual Attention on the Sphere

The continuous wavelet transform on conic sections

A Multi-Lead Ecg Classification Based On Random Projection Features

Stereographic Wavelet Frames on the Sphere

Multiresolution Motion Estimation for Omnidirectional Images

Scale Invariant Feature Transform on the Sphere: Theory and Applications

Multimedia Teaching on WWW: a New Approach

Stereographic Frames of Wavelets on the Sphere

Wavelets on the 2-Hyperboloid

Discrete Wavelet Frames on the Sphere

Continuous Wavelet Transform on the Hyperboloid

Scale-space analysis and active contours for omnidirectional images

On-line Digital Image processing Lab-Sessions

Specification for Digital Image Processing On-line Lab-sessions

Graphical User Interface and MATLAB Web Server for Multimedia Teaching on WWW