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arXiv · 1911.11454

Preservation of Piecewise Constancy under TV Regularization with Rectilinear Anisotropy

Clemens Kirisits·Eric Setterqvist·Otmar Scherzer
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Abstract

A recent result by Lasica, Moll and Mucha about the $\ell^1$-anisotropic Rudin-Osher-Fatemi model in $\mathbb{R}^2$ asserts that the solution is piecewise constant on a rectilinear grid, if the datum is. By means of a new proof we extend this result to $\mathbb{R}^n$. The core of our proof consists in showing that averaging operators associated to certain rectilinear grids map subgradients of the $\ell^1$-anisotropic total variation seminorm to subgradients.

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Clemens Kirisits, Eric Setterqvist, Otmar Scherzer. 2019-11-26. Preservation of Piecewise Constancy under TV Regularization with Rectilinear Anisotropy. https://doi.org/10.1007/978-3-030-22368-7_40

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