Jean-Michel Morel (PhD 1980) is Professor of Applied Mathematics at the Ecole Normale Superieure de Cachan since 1997. He started his career in 1979 as assistant professor in Marseille Luminy, then moved in 1984 to University Paris Dauphine where he was promoted professor in 1992. His research is focused since 1990 on the mathematical analysis of image analysis and processing. He has received the Philip Morris Prize of Mathematics (1991), the Junior Institut Universitaire de France (1992), Prix Sciences et Defense (1996), Classe exceptionnelle 2001 and three IEEE best paper awards (ICIP 97, ICASSP 05, and CVPR 05.) He has coauthored with S. Solimini a book on Variational Methods in Image Segmentation (Birkhauser 1994) and with Agnes Desolneux and Lionel Moisan a book on Computation Gestalt Theory (Springer, 2008). He has advised 31 PhD's and is associate editor of five journals in applied mathematics and image analysis. He is also the editor in charge of Applied Mathematics for Springer Lecture Notes of Mathematics. Since 2002, Jean-Michel Morel belongs to the ISI list of highly cited mathematicians (http://isihighlycited.com/). Frederic Sur is assistant professor of mathematics and computer science at Ecole des Mines de Nancy and conducts his research at Loria laboratory. His research interest is computer vision, from low-level features definition to structure and motion problems. He defended his PhD thesis in applied mathematics and image analysis in 2004 at Ecole Normale Superieure de Cachan. Then he held a postdoctoral position on statistical learning theory at Loria. Jose-Luis Lisani received the Ph.D.degree on applied mathematics by the Universities of Paris-Dauphine (France) and of Illes Balears (Spain) in 2001. He is currently assistant professor of applied mathematics at the University of Illes Balears (Spain) and collaborates with the CMLA laboratory at ENS Cachan (France) and Cognitech Inc. (USA). His current research interests include image and video processing with applications to video-surveillance, database indexing and 3D images analysis. Pablo Muse received the Ph.D. degree in applied mathematics from Ecole Normale Superieure de Cachan, France, in 2004. From 2005 to 2006 he was with Cognitech, Inc., Pasadena, CA, USA, where he worked on computer vision and image processing applications. Then he held a postdoctoral position on applied mathematics at the Seismological Laboratory, California Institute of Technology. Since 2008, he has been an assistant professor of electrical engineering at the Facultad de Ingenieria, Universidad de la Republica, Uruguay. His research interests include signal and image processing and analysis. Frederic Cao is researcher in applied mathematics and computer vision, with INRIA, France. He obtained a PhD in 2000, then successively worked for the French Defence Agency, INRIA (National Institute of research in Computer Science), Cognitech Inc. He is currently with DxO Labs, as Research Director. His topics of research are shape recognition, motion analysis or digital photography. He is author of a book on geometric curve evolution and image processing, published as a volume of Lecture Notes in Mathematics, Springer.

• Extracting Image boundaries.- Extracting Meaningful Curves from Images.- Level Line Invariant Descriptors.- Robust Shape Directions.- Invariant Level Line Encoding.- Recognizing Level Lines.- A Contrario Decision: the LLD Method.- Meaningful Matches: Experiments on LLD and MSER.- Grouping Shape Elements.- Hierarchical Clustering and Validity Assessment.- Grouping Spatially Coherent Meaningful Matches.- Experimental Results.- The SIFT Method.- The SIFT Method.- Securing SIFT with A Contrario Techniques.