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arXiv · 1710.00798

Measure-Valued Variational Models with Applications to Diffusion-Weighted Imaging

Thomas Vogt·Jan Lellmann
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Abstract

We develop a general mathematical framework for variational problems where the unknown function assumes values in the space of probability measures on some metric space. We study weak and strong topologies and define a total variation seminorm for functions taking values in a Banach space. The seminorm penalizes jumps and is rotationally invariant under certain conditions. We prove existence of a minimizer for a class of variational problems based on this formulation of total variation, and provide an example where uniqueness fails to hold. Employing the Kan\-torovich-Rubinstein transport norm from the theory of optimal transport, we propose a variational approach for the restoration of orientation distribution function (ODF)-valued images, as commonly used in Diffusion MRI. We demonstrate that the approach is numerically feasible on several data sets.

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Thomas Vogt, Jan Lellmann. 2017-10-02. Measure-Valued Variational Models with Applications to Diffusion-Weighted Imaging. https://doi.org/10.1007/s10851-018-0827-8

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