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arXiv · 2301.03840

Discrete Morse Functions and Watersheds

Gilles Bertrand·Nicolas Boutry·Laurent Najman
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Abstract

Any watershed, when defined on a stack on a normal pseudomanifold of dimension d, is a pure (d -- 1)-subcomplex that satisfies a drop-of-water principle. In this paper, we introduce Morse stacks, a class of functions that are equivalent to discrete Morse functions. We show that the watershed of a Morse stack on a normal pseudomanifold is uniquely defined, and can be obtained with a linear-time algorithm relying on a sequence of collapses. Last, we prove that such a watershed is the cut of the unique minimum spanning forest, rooted in the minima of the Morse stack, of the facet graph of the pseudomanifold.

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Gilles Bertrand, Nicolas Boutry, Laurent Najman. 2023-01-10. Discrete Morse Functions and Watersheds. https://arxiv.org/abs/2301.03840

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