Publications de Oscar Divorra Escoda

Geometric Video Approximation Using Weighted Matching Pursuit

Michel Bierlaire, Pierre Vandergheynst, Gianluca Monaci, Oscar Divorra Escoda

In recent years, many works on geometric image representation have appeared in the literature. Geometric video representation has not received such an important attention so far, and only some initial works in the area have been presented. Works on geometr ...

2009

Analysis of Multimodal Sequences Using Geometric Video Representations

Pierre Vandergheynst, Gianluca Monaci, Oscar Divorra Escoda

This paper presents a novel method to correlate audio and visual data generated by the same physical phenomenon, based on sparse geometric representation of video sequences. The video signal is modeled as a sum of geometric primitives evolving through time ...

2006

Ventricular and Atrial Activity Estimation Through Sparse ECG Signal Decompositions

Pierre Vandergheynst, Jean-Marc Vesin, Mathieu Lemay, Lorenzo Granai, Oscar Divorra Escoda

This paper explores a novel approach for ventricular and atrial activities estimation in electrocardiogram (ECG) signals, based on sparse source separation. Sparse decompositions of ECG over signal-adapted multi-component dictionaries can lead to natural s ...

2006

On the Use of A Priori Information for Sparse Signal Approximations

Pierre Vandergheynst, Lorenzo Granai, Oscar Divorra Escoda

Recent results have underlined the importance of incoherence in redundant dictionaries for a good behavior of decomposition algorithms like Matching and Basis Pursuits. However, appropriate dictionaries for a given application may not necessarily be able t ...

2006

Toward sparse and geometry adapted video approximations

Oscar Divorra Escoda

Video signals are sequences of natural images, where images are often modeled as piecewise-smooth signals. Hence, video can be seen as a 3D piecewise-smooth signal made of piecewise-smooth regions that move through time. Based on the piecewise-smooth model ...

EPFL2005