Tikhonov Regularization of Circle-Valued Signals

Laurent Condat

doi:10.1109/tsp.2022.3179816

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arXiv · 2108.02602

Tikhonov Regularization of Circle-Valued Signals

Laurent Condat

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Abstract

It is common to have to process signals or images whose values are cyclic and can be represented as points on the complex circle, like wrapped phases, angles, orientations, or color hues. We consider a Tikhonov-type regularization model to smoothen or interpolate circle-valued signals defined on arbitrary graphs. We propose a convex relaxation of this nonconvex problem as a semidefinite program, and an efficient algorithm to solve it.

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Laurent Condat. 2021-08-05. Tikhonov Regularization of Circle-Valued Signals. https://doi.org/10.1109/tsp.2022.3179816

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