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Title: Elastic Shape Analysis of Surfaces with Second-Order Sobolev Metrics: A Comprehensive Numerical Framework
Abstract This paper introduces a set of numerical methods for Riemannian shape analysis of 3D surfaces within the setting of invariant (elastic) second-order Sobolev metrics. More specifically, we address the computation of geodesics and geodesic distances between parametrized or unparametrized immersed surfaces represented as 3D meshes. Building on this, we develop tools for the statistical shape analysis of sets of surfaces, including methods for estimating Karcher means and performing tangent PCA on shape populations, and for computing parallel transport along paths of surfaces. Our proposed approach fundamentally relies on a relaxed variational formulation for the geodesic matching problem via the use of varifold fidelity terms, which enable us to enforce reparametrization independence when computing geodesics between unparametrized surfaces, while also yielding versatile algorithms that allow us to compare surfaces with varying sampling or mesh structures. Importantly, we demonstrate how our relaxed variational framework can be extended to tackle partially observed data. The different benefits of our numerical pipeline are illustrated over various examples, synthetic and real.  more » « less
Award ID(s):
1953244 1912037 1953267 1945224 2402555
NSF-PAR ID:
10447078
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
International Journal of Computer Vision
Volume:
131
Issue:
5
ISSN:
0920-5691
Page Range / eLocation ID:
1183 to 1209
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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