EURO 2024 Copenhagen
Abstract Submission

EURO-Online login

2694. Accelerating convergent Plug-and-Play methods

Invited abstract in session MC-34: Optimization and learning for data science and imaging (Part III), stream Advances in large scale nonlinear optimization.

Monday, 12:30-14:00
Room: 43 (building: 303A)

Authors (first author is the speaker)

1. Andrea Sebastiani
Department of Physics, Informatics and Mathematics, University of Modena and Reggio Emilia
2. Tatiana Bubba
University of Bath
3. Luca Ratti
University of Bologna

Abstract

Plug-and-Play methods are obtained replacing with off-the-shelf denoisers, the proximal operator in many first order proximal optimization algorithms. Under suitable hypothesis, it is possible to derive the functional whose proximal operator corresponds to a particular class of denoisers, referred to as Gradient Step denoisers. This characterization result allows for the interpretation of Plug-and-Play schemes as the minimization of an underlying non-convex cost function, enabling the study of the convergence of such methods. In particular, this analysis can be further extended to ensure the convergence of several accelerated methods. The non-convexity of the cost function strongly limits any improvemnt in the theoretical convergence rate. However, the numerical experiments empirically demonstrate the benefits of this acceleration, that allows to reduce the computational demand and workload required to compute the reconstruction of an image.

Keywords

Status: accepted


Back to the list of papers