Computing the Bottleneck Distance between Persistent Homology Transforms
Michael Kerber, Elena Xinyi Wang
TL;DR
The paper tackles the problem of comparing Persistent Homology Transforms by computing the maximum bottleneck distance across all directions, providing the first algorithms with provable bounds in both 2D and 3D. It introduces an event-driven, randomized band-refinement framework that navigates a combinatorial set of candidate extrema, updating bottleneck matchings through diagram changes with vineyard updates and augmenting-path searches. In 2D, it achieves {O(n^3)} time for the max distance and {O(n^5)} for the integral variant, while in 3D it attains {O(n^5)} time for the max distance, leveraging an arrangement-based approach on the sphere. As a byproduct, the integral distance in 2D is improved to {O(n^5)}. These results enable efficient, exact PHT comparisons on moderate-scale data, with potential extensions to related directional transforms in topological data analysis.
Abstract
The Persistent Homology Transform (PHT) summarizes a shape in $\R^m$ by collecting persistence diagrams obtained from linear height filtrations in all directions on $\mathbb{S}^{m-1}$. It enjoys strong theoretical guarantees, including continuity, stability, and injectivity on broad classes of shapes. A natural way to compare two PHTs is to use the bottleneck distance between their diagrams as the direction varies. Prior work has either compared PHTs by sampling directions or, in 2D, computed the exact \textit{integral} of bottleneck distance over all angles via a kinetic data structure. We improve the integral objective to $\tilde O(n^5)$ in place of earlier $\tilde O(n^6)$ bound. For the \textit{max} objective, we give a $\tilde O(n^3)$ algorithm in $\mathbb{R}^2$ and a $\tilde O(n^5)$ algorithm in $\mathbb{R}^3$.
