English

The Mid-sphere Cousin of the Medial Axis Transform

Computational Geometry 2025-04-22 v1 Algebraic Topology

Abstract

The medial axis of a smoothly embedded surface in R3\mathbb{R}^3 consists of all points for which the Euclidean distance function on the surface has at least two minima. We generalize this notion to the mid-sphere axis, which consists of all points for which the Euclidean distance function has two interchanging saddles that swap their partners in the pairing by persistent homology. It offers a discrete-algebraic multi-scale approach to computing ridge-like structures on the surface. As a proof of concept, an algorithm that computes stair-case approximations of the mid-sphere axis is provided.

Keywords

Cite

@article{arxiv.2504.14743,
  title  = {The Mid-sphere Cousin of the Medial Axis Transform},
  author = {Herbert Edelsbrunner and Elizabeth Stephenson and Martin Hafskjold Thoresen},
  journal= {arXiv preprint arXiv:2504.14743},
  year   = {2025}
}