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arXiv · 1405.1594

Disparity and Optical Flow Partitioning Using Extended Potts Priors

Xiaohao Cai·Jan Henrik Fitschen·Mila Nikolova·Gabriele Steidl·Martin Storath
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Abstract

This paper addresses the problems of disparity and optical flow partitioning based on the brightness invariance assumption. We investigate new variational approaches to these problems with Potts priors and possibly box constraints. For the optical flow partitioning, our model includes vector-valued data and an adapted Potts regularizer. Using the notation of asymptotically level stable functions we prove the existence of global minimizers of our functionals. We propose a modified alternating direction method of minimizers. This iterative algorithm requires the computation of global minimizers of classical univariate Potts problems which can be done efficiently by dynamic programming. We prove that the algorithm converges both for the constrained and unconstrained problems. Numerical examples demonstrate the very good performance of our partitioning method.

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Xiaohao Cai, Jan Henrik Fitschen, Mila Nikolova, Gabriele Steidl, Martin Storath. 2014-05-07. Disparity and Optical Flow Partitioning Using Extended Potts Priors. https://doi.org/10.1093/imaiai%2Fiau010

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