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arXiv · 1801.04172

Fast iterative solvers for an optimal transport problem

Roland Herzog·John W. Pearson·Martin Stoll
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Abstract

Optimal transport problems pose many challenges when considering their numerical treatment. We investigate the solution of a PDE-constrained optimisation problem subject to a particular transport equation arising from the modelling of image metamorphosis. We present the nonlinear optimisation problem, and discuss the discretisation and treatment of the nonlinearity via a Gauss--Newton scheme. We then derive preconditioners that can be used to solve the linear systems at the heart of the (Gauss--)Newton method. With the optical flow in mind, we further propose the reduction of dimensionality by choosing a radial basis function discretisation that uses the centres of superpixels as the collocation points. Again, we derive suitable preconditioners that can be used for this formulation.

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Roland Herzog, John W. Pearson, Martin Stoll. 2018-01-12. Fast iterative solvers for an optimal transport problem. https://arxiv.org/abs/1801.04172

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