Symmetric Volume Maps: Order-Invariant Volumetric Mesh Correspondence with Free Boundary

TL;DR

This paper introduces a novel method for volumetric shape correspondence using tetrahedral meshes that ensures order-invariance and favors near-isometric mappings, applicable to medical imaging and simulation data.

Contribution

It presents a symmetry-preserving, distortion-minimizing approach for volumetric mesh correspondence, extending shape matching to 3D volumes with theoretical insights.

Findings

Produces low-distortion volumetric correspondences

Aligns closely to shape boundaries in diverse datasets

Favors near-isometric mappings

Abstract

Although shape correspondence is a central problem in geometry processing, most methods for this task apply only to two-dimensional surfaces. The neglected task of volumetric correspondence--a natural extension relevant to shapes extracted from simulation, medical imaging, and volume rendering--presents unique challenges that do not appear in the two-dimensional case. In this work, we propose a method for mapping between volumes represented as tetrahedral meshes. Our formulation minimizes a distortion energy designed to extract maps symmetrically, i.e., without dependence on the ordering of the source and target domains. We accompany our method with theoretical discussion describing the consequences of this symmetry assumption, leading us to select a symmetrized ARAP energy that favors isometric correspondences. Our final formulation optimizes for near-isometry while matching the boundary. We demonstrate our method on a diverse geometric dataset, producing low-distortion matchings that align closely to the boundary.