This project deals with spaces of manifold-valued curves and associated shape spaces, and is based on Riemannian tools for elastic shape analysis. We plan to study certain geometrically and physically motivated subspaces and to develop and apply a variational discrete-time framework for numerically solving the optimal correspondence problem and for consistently computing fundamental building blocks of Riemannian geometry. These include parallel transport, shortest paths as well as exponential and logarithmic mappings for these spaces. A desirable goal in many applications is to perform statistical analysis on the underlying infinite dimensional spaces, e.g., to capture the variability of trajectories and characterize their role in a large complex system, compute the mean, and perform classification or principal component analysis. For these purposes, we aim to develop robust and efficient schemes for approximation and interpolation of unparameterized curves and, in particular, a novel spline approach for data-driven modeling and longitudinal statistical analysis. Moreover, we extend some Euclidean results to general Riemannian manifolds. Much of the work will be devoted to applying the proposed approach to datasets from the broad areas of computer vision and morphology, including examples from epidemiology and molecular biology. The work will focus on intrinsic and constructive approaches and implement them as open source software.

 

Publications

2024
De Casteljau's Algorithm in Geometric Data Analysis: Theory and Application Computer Aided Geometric Design, Vol.110, p. 102288, 2024 Martin Hanik, Esfandiar Navayazdani, Christoph von Tycowicz BibTeX
arXiv
DOI
Elastic Shape Analysis on Manifolds
On Geodesics in the Spaces of Constrained Curves Journal of Differential Geometry and its Applications, 2024 (revision under review) Esfandiar Navayazdani BibTeX
arXiv
Elastic Shape Analysis on Manifolds
2023
Elastic Analysis of Augmented Curves and Constrained Surfaces Proc. of IAPR Third International Conference on Discrete Geometry and Mathematical Morphology, pp. 353-363, Springer Lecture Notes in Computer Science, 2023 Esfandiar Navayazdani BibTeX
arXiv
DOI
Elastic Shape Analysis on Manifolds
Sasaki Metric for Spline Models of Manifold-Valued Trajectories Computer Aided Geometric Design, Vol.104, p. 102220, 2023 Esfandiar Navayazdani, Felix Ambellan, Martin Hanik, Christoph von Tycowicz BibTeX
arXiv
DOI
Elastic Shape Analysis on Manifolds
2022
A Hierarchical Geodesic Model for Longitudinal Analysis on Manifolds Journal of Mathematical Imaging and Vision, 64(4), pp. 395-407, 2022 (preprint available as ) Esfandiar Nava-Yazdani, Hans-Christian Hege, Christoph von Tycowicz BibTeX
DOI
Elastic Shape Analysis on Manifolds
ICLR 2022 Challenge for Computational Geomerty & Topology: Design and Results Proceedings of Topology, Algebra, and Geometry in Learning, pp. 269-276, Vol.196, Proceedings of Machine Learning Research, 2022 Adele Myers, Saiteja Utpala, Shubham Talbar, Sophia Sanborn, Christian Shewmake, Claire Donnat, Johan Mathe, Umberto Lupo, Rishi Sonthalia, Xinyue Cui, Tom Szwagier, Arthur Pignet, Andri Bergsson, Søren Hauberg, Dmitriy Nielsen, Stefan Sommer, David Klindt, Erik Hermansen, Melvin Vaupel, Benjamin Dunn, Jeffrey Xiong, Noga Aharony, Itsik Pe’er, Felix Ambellan, Martin Hanik, Esfandiar Navayazdani, Christoph von Tycowicz, Nina Miolane PDF
BibTeX
arXiv
Elastic Shape Analysis on Manifolds
SHREC 2022 Track on Online Detection of Heterogeneous Gestures Computers and Graphics, Vol.107, pp. 241-251, 2022 Ariel Caputo, Marco Emporio, Andrea Giachetti, Marco Cristani, Guido Borghi, Andrea D'Eusanio, Minh-Quan Le, Hai-Dang Nguyen, Minh-Triet Tran, Felix Ambellan, Martin Hanik, Esfandiar Navayazdani, Christoph von Tycowicz BibTeX
arXiv
DOI
Elastic Shape Analysis on Manifolds