[1] University Joseph Fourier, 38041 Grenoble, France
[2] Image Pervasive Access Lab, Centre National de la Recherch´e Scientifique, Unit Mixed International, Singapore 2955, Singapore
[3] Sorbonne Universit´es, University of Pierre and Marie Curie, Unit Mixed International 2955, 75005 Paris, France
[4] Image and Pervasive Access Laboratory, Singapore