A $\operatorname{prox}$-Based Semi-Smooth Newton Method for TV-Minimization

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Bartels, Sören, Kaltenbach, Alex
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913153266221056
author Bartels, Sören
Kaltenbach, Alex
author_facet Bartels, Sören
Kaltenbach, Alex
contents In this paper, we devise a $\operatorname{prox}$-based semi-smooth Newton method for the non-differentiable TV-minimization problem. To this end, the primal-dual optimality conditions are reformulated as a nonlinear operator equation with Newton-(type-)differentiable structure. We investigate the question of well-posedness of the resulting semi-smooth Newton scheme in the infinite-dimensional setting and identify structural properties of the associated Newton-type derivatives. For a conforming finite element discretization, we prove that the resulting semi-smooth Newton method is globally well-posed and locally super-linearly convergent. The approach extends to a large class of convex minimization problems, coincides with established semi-smooth Newton methods for obstacle problems, satisfies a primal-dual invariance, and, under suitable additional assumptions, is well-posed in the infinite-dimensional setting. Numerical experiments indicate a robust practical performance of the proposed method, including reliable reduction of the discrete primal-dual gap estimator to machine precision, robustness with respect to the choice of proximity parameters, an improved convergence basin compared to a canonical primal semi-smooth Newton method, and effective performance even for quadratically graded meshes using only a mesh-independent initialization criterion.
format Preprint
id arxiv_https___arxiv_org_abs_2605_22728
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A $\operatorname{prox}$-Based Semi-Smooth Newton Method for TV-Minimization
Bartels, Sören
Kaltenbach, Alex
Numerical Analysis
Optimization and Control
49M15, 65K10, 65N30, 49M29, 49J52, 90C25, 94A08
In this paper, we devise a $\operatorname{prox}$-based semi-smooth Newton method for the non-differentiable TV-minimization problem. To this end, the primal-dual optimality conditions are reformulated as a nonlinear operator equation with Newton-(type-)differentiable structure. We investigate the question of well-posedness of the resulting semi-smooth Newton scheme in the infinite-dimensional setting and identify structural properties of the associated Newton-type derivatives. For a conforming finite element discretization, we prove that the resulting semi-smooth Newton method is globally well-posed and locally super-linearly convergent. The approach extends to a large class of convex minimization problems, coincides with established semi-smooth Newton methods for obstacle problems, satisfies a primal-dual invariance, and, under suitable additional assumptions, is well-posed in the infinite-dimensional setting. Numerical experiments indicate a robust practical performance of the proposed method, including reliable reduction of the discrete primal-dual gap estimator to machine precision, robustness with respect to the choice of proximity parameters, an improved convergence basin compared to a canonical primal semi-smooth Newton method, and effective performance even for quadratically graded meshes using only a mesh-independent initialization criterion.
title A $\operatorname{prox}$-Based Semi-Smooth Newton Method for TV-Minimization
topic Numerical Analysis
Optimization and Control
49M15, 65K10, 65N30, 49M29, 49J52, 90C25, 94A08
url https://arxiv.org/abs/2605.22728