CHESS

The next CHESS meeting will held today, Tuesday March 15, in room Mont-Blanc, at 10:00 AM.

1) There will be first two talks

Lucas Drumetz (Univ. Grenoble Alpes)
Title: Optimization tools for signal and image processing: application to spectral unmixing of hyperspectral images (2/2)

This second part (the first part on optimization methods was presented on March 15) of the talk will be focused on applications in spectral unmixing of hyperspectral imaging.

Paolo Zanini (Univ. Grenoble Alpes)
Title: Parameters estimate of Riemannian Gaussian distribution in the manifold of covariance matrices

The study of P(m) , the manifold of m × m Symmetric Positive Definite matrices, has recently become widely popular in many engineering applications, like radar signal processing, mechanics, computer vision, image processing, and medical imaging. A large body of literature is devoted to the barycentre of a set of points in P(m) and the concept of barycentre has become essential to many applications and procedures, for instance classification of SPD matrices. However this concept is often used alone in order to define and characterize a set of points. Less attention is paid to the characterization of the shape of samples in the manifold, or to the definition of a probabilistic model, to represent the statistical variability of data in Pm. Here we consider Gaussian distributions and mixtures of Gaussian distributions on P(m). In particular we deal with parameter estimation of such distributions. This problem, while it is simple in the manifold P(2), becomes harder for higher dimensions, since there are some quantities involved whose analytic expression is difficult to derive. In this paper we introduce a smooth estimate of these quantities using convex cubic spline, and we show that in this case the parameters estimate is coherent with theoretical results. We also present some simulations and a real EEG data analysis

2) Information/exhibition on Redmine (P. Pignède and R. Phlypo)

3) Future event: scientific DECODA/CHESS days in July 2016 (K. Usevitch and R. Phlypo)

4) "Help" talk, if any ???