Multigrid methods for total variation

Felipe Guerra; Tuomo Valkonen

doi:10.1007/978-3-031-92369-2_1

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arXiv · 2502.18659

Multigrid methods for total variation

Felipe Guerra·Tuomo Valkonen

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Abstract

Based on a nonsmooth coherence condition, we construct and prove the convergence of a forward-backward splitting method that alternates between steps on a fine and a coarse grid. Our focus is a total variation regularised inverse imaging problems, specifically, their dual problems, for which we develop in detail the relevant coarse-grid problems. We demonstrate the performance of our method on total variation denoising and magnetic resonance imaging.

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Felipe Guerra, Tuomo Valkonen. 2025-02-25. Multigrid methods for total variation. https://doi.org/10.1007/978-3-031-92369-2_1

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