An N-Point Linear Solver for Line and Motion Estimation with Event Cameras

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Gao, Ling, Gehrig, Daniel, Su, Hang, Scaramuzza, Davide, Kneip, Laurent
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866909319565410304
author Gao, Ling
Gehrig, Daniel
Su, Hang
Scaramuzza, Davide
Kneip, Laurent
author_facet Gao, Ling
Gehrig, Daniel
Su, Hang
Scaramuzza, Davide
Kneip, Laurent
contents Event cameras respond primarily to edges--formed by strong gradients--and are thus particularly well-suited for line-based motion estimation. Recent work has shown that events generated by a single line each satisfy a polynomial constraint which describes a manifold in the space-time volume. Multiple such constraints can be solved simultaneously to recover the partial linear velocity and line parameters. In this work, we show that, with a suitable line parametrization, this system of constraints is actually linear in the unknowns, which allows us to design a novel linear solver. Unlike existing solvers, our linear solver (i) is fast and numerically stable since it does not rely on expensive root finding, (ii) can solve both minimal and overdetermined systems with more than 5 events, and (iii) admits the characterization of all degenerate cases and multiple solutions. The found line parameters are singularity-free and have a fixed scale, which eliminates the need for auxiliary constraints typically encountered in previous work. To recover the full linear camera velocity we fuse observations from multiple lines with a novel velocity averaging scheme that relies on a geometrically-motivated residual, and thus solves the problem more efficiently than previous schemes which minimize an algebraic residual. Extensive experiments in synthetic and real-world settings demonstrate that our method surpasses the previous work in numerical stability, and operates over 600 times faster.
format Preprint
id arxiv_https___arxiv_org_abs_2404_00842
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle An N-Point Linear Solver for Line and Motion Estimation with Event Cameras
Gao, Ling
Gehrig, Daniel
Su, Hang
Scaramuzza, Davide
Kneip, Laurent
Computer Vision and Pattern Recognition
Event cameras respond primarily to edges--formed by strong gradients--and are thus particularly well-suited for line-based motion estimation. Recent work has shown that events generated by a single line each satisfy a polynomial constraint which describes a manifold in the space-time volume. Multiple such constraints can be solved simultaneously to recover the partial linear velocity and line parameters. In this work, we show that, with a suitable line parametrization, this system of constraints is actually linear in the unknowns, which allows us to design a novel linear solver. Unlike existing solvers, our linear solver (i) is fast and numerically stable since it does not rely on expensive root finding, (ii) can solve both minimal and overdetermined systems with more than 5 events, and (iii) admits the characterization of all degenerate cases and multiple solutions. The found line parameters are singularity-free and have a fixed scale, which eliminates the need for auxiliary constraints typically encountered in previous work. To recover the full linear camera velocity we fuse observations from multiple lines with a novel velocity averaging scheme that relies on a geometrically-motivated residual, and thus solves the problem more efficiently than previous schemes which minimize an algebraic residual. Extensive experiments in synthetic and real-world settings demonstrate that our method surpasses the previous work in numerical stability, and operates over 600 times faster.
title An N-Point Linear Solver for Line and Motion Estimation with Event Cameras
topic Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2404.00842