Personne
Oscar Divorra Escoda
Publications associées (25)
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 ...
2009Ventricular and Atrial Activity Estimation Through Sparse ECG Signal Decompositions
Pierre Vandergheynst, 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 ...
2006On 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 ...
2006Analysis 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 ...
2006Toward sparse and geometry adapted video approximations
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 ...
EPFL2005Sparse Decompositions for Ventricular and Atrial Activity Separation
Pierre Vandergheynst, Mathieu Lemay, Lorenzo Granai, Oscar Divorra Escoda
Atrial Fibrillation (AF) is the most common type of human arrhythmia. Beside its clinical description as absolute arrhythmia, its diagnosis has been assessed for years by visual inspection of the surface electrocardiogram (ECG). Due to the much higher ampl ...
2005Ventricular and Atrial Activity Estimation Through Sparse ECG Signal Decompositions
Pierre Vandergheynst, 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 ...
2005Analysis 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 ...
2005Analysis of Multimodal Signals Using Redundant Representations [Winner of IBM Student Paper Award]
Pierre Vandergheynst, Gianluca Monaci, Oscar Divorra Escoda
In this work we explore the potentialities of a framework for the representation of audio-visual signals using decompositions on overcomplete dictionaries. Redundant decompositions may describe audio-visual sequences in a concise fashion, preserving good r ...
2005Intra-Adaptive Motion-Compensated Lifted Wavelets for Video Coding
Pierre Vandergheynst, Oscar Divorra Escoda
This paper investigates intra-adaptive wavelets for video coding with frame-adaptive motion-compensated lifted wavelet transforms. With motion-compensated lifted wavelets, the temporal wavelet decomposition operates along motion trajectories. However, vali ...
EUSIPCO2005