Denoising Hyperbolic-Valued Data by Relaxed Regularizations

Robert Beinert; Jonas Bresch

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arXiv · 2410.16149

Denoising Hyperbolic-Valued Data by Relaxed Regularizations

Robert Beinert·Jonas Bresch

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Abstract

We introduce a novel relaxation strategy for denoising hyperbolic-valued data. The main challenge is here the non-convexity of the hyperbolic sheet. Instead of considering the denoising problem directly on the hyperbolic space, we exploit the Euclidean embedding and encode the hyperbolic sheet using a novel matrix representation. For denoising, we employ the Euclidean Tikhonov and total variation (TV) model, where we incorporate our matrix representation. The major contribution is then a convex relaxation of the variational ans\"atze allowing the utilization of well-established convex optimization procedures like the alternating directions method of multipliers (ADMM). The resulting denoisers are applied to a real-world Gaussian image processing task, where we simultaneously restore the pixelwise mean and standard deviation of a retina scan series.

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BibTeX RIS

Robert Beinert, Jonas Bresch. 2024-10-21. Denoising Hyperbolic-Valued Data by Relaxed Regularizations. https://arxiv.org/abs/2410.16149

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