1. LaBRI CNRS, UMR 5800, Université Bordeaux, 33405 Talence Cedex, France
2. University of Rennes I, CNRS UMR 6074, IRISA, 35042 Rennes, France
3. INRIA, VisAGeS U746 Unit/Project, IRISA, 35042 Rennes, France
4. INSERM, VisAGeS U746 Unit/Project, IRISA, 35042 Rennes, France
5. Technicolor Corporate Research Rennes Laboratory, 1 Avenue de Belle Fontaine, CS 17616, 65576 Cesson-Sévigné Cedex, France
6. University Hospital of Rennes, 35043 Rennes, France