GPU-Based Homotopy Continuation for Minimal Problems in Computer Vision
Résumé
Systems of polynomial equations arise frequently in com-
puter vision, especially in multiview geometry problems. Tra-
ditional methods for solving these systems typically aim to
eliminate variables to reach a univariate polynomial, e.g.,
a tenth-order polynomial for 5-point pose estimation, using
clever manipulations, or more generally using Grobner ba-
sis, resultants, and elimination templates, leading to success-
ful algorithms for multiview geometry and other problems.
However, these methods do not work when the problem is
complex and when they do, they face efficiency and stability
issues. Homotopy Continuation (HC) can solve more com-
plex problems without the stability issues, and with guaran-
tees of a global solution, but they are known to be slow. In
this paper we show that HC can be parallelized on a GPU,
showing significant speedups up to 26 times on polynomial
benchmarks. We also show that GPU-HC can be generically
applied to a range of computer vision problems, including 4-
view triangulation and trifocal pose estimation with unknown
focal length, which cannot be solved with elimination tem-
plate but they can be efficiently solved with HC. GPU-HC
opens the door to easy formulation and solution of a range of
computer vision problems
Mots clés
Multiview geometry problems
Tenth-order polynomial
Elimination template
Stability issues
Complex problems
Polynomial benchmarks
GPU-HC
Computer vision problems
Trifocal pose estimation
Minimal problems
Polynomial equations
GPU-based homotopy continuation
Univariate polynomial
5-point pose estimation
Clever manipulations
Grobner basis
Elimination templates
4-view triangulation
Unknown focal length
Face efficiency