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Showing posts from 2013

Image processing for materials characterization (ICIP 2014, special session)

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ICIP 2014 , the IEEE International Conference on Image Processing, will take place in Paris (la Défense, to be honest) during 27-30 October 2014. The twenty special sessions have been announced (see below). One is devoted to the exciting field of Materials science: " Image processing for materials characterization ", with one introductory and five invited papers . ICIP 2014 Special Session " Image processing for materials characterization " CLICK THE PICTURE FOR THE DEDICATED PAGE  The deadline for paper submission is 14 February 2014. We encourage interested authors to submit as many papers as possible around this topic ( ICIP 2014 submission information ), and to warn one the special session organizers. Beware: the existence of the special session on " Image processing for materials characterization " does not grant , by no mean, acceptance or even higher odds to the main conference tracks. Maxime Moreaud (@IFPEN dot fr, with a d

Géométrie espace-temps

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Une jolie série historique sur la géométrisation progressive du monde observé, par les philosophes et les scientifiques, en série d'épisodes de 10 minutes. La géométrie de l'espace et du temps  1 Introduction : physique et géométrie, naissance de l'esprit scientifique (de la narration mythique à l'explication). La géométrie de l'espace et du temps  2 Une vision du monde totalement géométrisée. L'harmonie et la symétrie, le cosmos, solides de Platon ou polyèdres réguliers, mis en relations avec les éléments, précurseurs des groupes de symétries. "Planète" veut dire "voyageur". Le dodécaèdre, plus proche de la sphère en symétrie, sert à représenter un cinquième élément. La géométrie de l'espace et du temps  3 La géométrie de l'espace et du temps  4 La géométrie de l'espace et du temps  5 La géométrie de l'espace et du temps  6 La géometrie de l'espace et du temps  7 La géometrie de l&

A Primal-Dual Proximal Algorithm for Sparse Template-Based Adaptive Filtering: Application to Seismic Multiple Removal

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A year ago we talked about a technique for Adaptive multiple subtraction with wavelet-based complex unary Wiener filters . The field of application is seismic signal processing . The fast and simple design was heuristic ( helping discovery, stimulating interest as a means of furthering investigation. based on experimentation), based on an appropriate combination of "a sparsifying transform" and a closed-form one-tap, sliding-window adaptive filter. To make it more pragmatic (based on observation and real-world models), an alternative approach uses proximal algorithms to incorporate sparsity priors, either on data in redundant frame transforms and in the short-support filter design. Here is the preprint: A Primal-Dual Proximal Algorithm for Sparse Template-Based Adaptive Filtering: Application to Seismic Multiple Removal and the version published by IEEE Transactions on Signal Processing . Unveiling meaningful geophysical information from seismic data requires

Multirate structures, multiscale decompositions: two years after

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Signal Processing Two years ago, in December 2011, a special issue of Signal Processing was published on the theme of Advances in Multirate Filter Bank Structures and Multiscale Representations . Eleven papers, ranging from 1D or 2D data, spanning topics from filter frame design to compression, browsing applications from audio to medical imaging. This issue was very rich in interesting papers , thanks to the authors and reviewers. Can one say a little more? Of course, bibliometrics or scientometrics generate a lot of debates. Generally, such indicators do not mean anything absolute, they may only serve as a ground for discussion. Let us just compare the figures with the journal statistics: Signal Processing has a two-year Impact Factor on 1.851 (2012). Special issue citation data is tabulated in the following array: Citation sources (2013/12/14) Elsevier ISI-Thomson Google Title Scopus WoS Scholar A Panorama on Multiscale Geometric Representations, Int

Marseille: from the Vieux Port with hole

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Following a quick trip to Marseille (my first one) for a discussion on directiona/geometric wavelets ( slides ) at the séminaire signal - apprentissage in LATP (Laboratoire d’Analyse Topologie et Probabilités) , a rough pinhole view of the "Vieux Port", on the bridge to the brand new museum MUCEM. Have to get back for a broader overview of the city.

Conference: Is there a place for beauty in our research? A few thoughts inspired by Richard Hamming

On Tuesday 15th of October (11:00 - 12:30) there will be a talk of general audience given by Leonid Libkin (University of Edinburgh) in Amphi Turing (Université Paris Diderot, Bâtiment Sophie Germain). Title: Is there a place for beauty in our research? A few thoughts inspired by Richard Hamming Abstract: In 1986, Richard Hamming gave a famous talk entitled "You and Your Research" , which discussed how to do really significant research with high impact. His main questions were: are the problems you work on important? Are they timely? What are the main open problems in your area? Can you attack them? If you are not working on them, why? Inspired by this, the University of Edinburgh started a series of Hamming seminars, in which the speakers are supposed to answer these questions about their research fields and their own research.   While preparing mine, I observed that, curiously enough, Hamming never talks about beauty in science and research: neither t

Ecole Analyse multirésolution pour l'image 2013 (ondelettes et cie)

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(M-band) Dual-tree wavelets Hilbert pairs on Haar and Riesz L’ École Analyse Multirésolution pour l'image se déroulera les 28 et 29 novembre au Creusot (en Bourgogne) . Une occasion de se rafraichir les idées, dans un cadre convivial, sur les techniques multi-échelles, en bancs de filtres et transformées en ondelettes, appliquées en 2 dimensions sur les images , les graphes, les maillages. Cette année, elle est co-organisée avec CORESA 2013 (COmpression et REprésentation des Signaux Audiovisuels,  d'autres conférences en traitement de signal et d'image ici ). Objectifs et programme : Laplacian, Mexican hat wavelet and multiscale edge detection Objectifs Les techniques d'analyse multirésolution et en particulier les techniques basées sur les ondelettes, sont des outils de plus en plus répandus pour le traitement du signal et de l'image qui trouvent de nombreuses applications (analyse, débruitage, segmentation, compression et codage, tatouage,…) dan

A touch of Henry Moore and the Nits

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Reclining figure, Henry Moore, Lincoln Center New York could as well have been Dutch. In 1609, English explorer Henry Hudson (according to wikipedia):  re-discovered the region, sailing for his employer the Dutch East India Company . He proceeded to sail up what he named the North River , also called the Mauritis River , and now known as the Hudson River , to the site of the present-day New York State capital of Albany in the belief that it might represent an oceanic tributary . When the river narrowed and was no longer saline , he realized it wasn't a sea passage and sailed back downriver. He made a ten-day exploration of the area and claimed the region for his employer. In 1614 the area between Cape Cod and Delaware Bay would be claimed by the Netherlands and called Nieuw-Nederland ( New Netherland ). The capital of Nieuw-Nederland was located in the southern tip of Manhattan. A last proof is the New York City flag, derived from the Prince's flag, th

Gas chromatography and 2D-gas chromatography for petroleum industry: The race for selectivity

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Almost a follow-up to Signal Processing for Chemical Sensing: ICASSP 2013 Special session : the book Gas chromatography and 2D-gas chromatography for petroleum industry: The race for selectivity , edited by Fabrice Bertoncini, Marion Courtiade-Tholance, Didier Thiébaut (2013, éditions Technip) is out. Our contribution lies in Chapter 3: "Data processing applied to GCxGC. Applications to the petroleum industry.". Detailed knowledge of petroleum products at molecular scale has always been essential to understand the mechanisms leading to their formation, to design thermodynamic and kinetic models employed in the refining processes and to predict their physical properties. In view of the complexity of petroleum products, very significant research efforts have been made over the past 15 years for improving relevant analytical techniques, especially in the field of Gas Chromatography in order to improve its separation power. The advent of comprehensive Two-dimensional Gas

Signal Processing for Chemical Sensing: ICASSP 2013 Special session

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ICASSP 2013 (International conference on acoustic, speech and signal processing) takes place at the end of May 2013 in Vancouver, Canada. The technical program is online . Among the numerous tracks and sessions, there were a special session on Signal Processing for Chemical Sensing (Friday, May 31, 08:00 - 10:00). The chairpersons were: Leonardo T. Duarte , Laurent Duval , Christian Jutten . Here are posted the slides ( all slides in a .zip file ) presented at the conference and paper abstracts. Typical chemical signals: 1D gas chromatogram Summary of the Special Session: This special session aims at showing some relevant problems in chemical engineering that can be addressed with classical or advanced methods of signal and image processing. It will be introduced by a tutorial paper, presented by the organizers, who will offer a large overview of issues which have been addressed in this application domain, like chemical analysis leading to PARAFAC/tensor methods,

Split gaussian mathematical constant?

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Assuming you have a standard Gaussian bell curve (in blue). Suppose that you want to cut it into two parts of equal areas, with an horizontal line.  Which fraction of the Gaussian peak height provides you with the red and the green curves, which sum up to the Gaussian, with equal surface integral (undr the red and the green cuves)? It turns out that, numerically, the fraction, on the y-axis, is about 0.3063622804625085, or one over 3.26410940175247 of the peak height. If one looks at the x-axis, one has to cut at +/- 1.538172262286592.\sigma, where \sigma is the usual Gaussian scale parameter. In practice, cutting the Gaussian at 3/10 of the height would be good enough, assuming sufficient, far to critical, sampling. Yet out of curiosity, i looked at several numerical constant tables, or even Plouffe's constant inverter , and did not find any of these three. So once again, the potential gaussian split constants  are: 0.3063622804625085 1.538172262286592 3.264109

W2 4 i3 (2D wavelets for iCube)

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Under the cryptic title dwells a nice invitation by Vincent Mazet to give a talk on a panorama of 2D wavelets at iCube-MIV : modèles, images et vision (Strasbourg University). Although the abstract is in french, slides are globish. For those who have an eye for finest details, Alfréd Haar and Frigyes Riesz , two prominent functional analysis and therefore wavelet contributors (albeit indirectly) are honored on this memorial at Szeged university. Vendredi 15 mars 2013, 10h30, A301, séminaire commun D-IRTS & École doctorale MSII Ondelettes et autres représentations bidimensionnelles, multi-échelles et géométriques pour le traitement d'images : un panorama Conférencier : Laurent Duval (IFP Energies nouvelles), avec Laurent Jacques , Caroline Chaux et Gabriel Peyré Résumé : La quête de représentations optimales en traitement d'images et vision par ordinateur se heurte à la richesse et la diversité des données bidimensionnelles. De nombreux travaux se sont cepe