WEISS , Pierre

This PhD contains contributions in numerical analysis and in computer vision. In the first part, we focus on the fast resolution, using first order methods, of convex optimization problems. Those problems appear naturally in many image processing tasks like image reconstruction, compressed sensing or texture+cartoon decompositions. They are...

In this paper, we present a new algorithm to solve some inverse problems coming from the field of image processing. The models we study consist in minimizing a regularizing, convex criterion under a convex and compact set. The main idea of our scheme consists in solving the underlying variational inequality with a proximal method rather than...

We propose some improvements of the Multiple Birth and Cut algorithm (MBC) in order to extract nuclei in 2D and 3D images. This algorithm based on marked point processes was proposed recently in (Gamal Eldin et al., 2012). We introduce a new contrast invariant energy that is robust to degradations encountered in fluorescence microscopy (e.g....

We propose an algorithm to segment 2D ellipses or 3D ellipsoids. This problem is of fundamental importance in various applications of cell biology. The algorithm consists of minimizing a contrast invariant energy defined on sets of non overlapping ellipsoids. This highly non convex problem is solved by combining a stochastic approach based on...