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arXiv · 1904.02663

Algebraic Characterization of Essential Matrices and Their Averaging in Multiview Settings

Yoni Kasten·Amnon Geifman·Meirav Galun·Ronen Basri
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Abstract

Essential matrix averaging, i.e., the task of recovering camera locations and orientations in calibrated, multiview settings, is a first step in global approaches to Euclidean structure from motion. A common approach to essential matrix averaging is to separately solve for camera orientations and subsequently for camera positions. This paper presents a novel approach that solves simultaneously for both camera orientations and positions. We offer a complete characterization of the algebraic conditions that enable a unique Euclidean reconstruction of $n$ cameras from a collection of $(^n_2)$ essential matrices. We next use these conditions to formulate essential matrix averaging as a constrained optimization problem, allowing us to recover a consistent set of essential matrices given a (possibly partial) set of measured essential matrices computed independently for pairs of images. We finally use the recovered essential matrices to determine the global positions and orientations of the $n$ cameras. We test our method on common SfM datasets, demonstrating high accuracy while maintaining efficiency and robustness, compared to existing methods.

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Yoni Kasten, Amnon Geifman, Meirav Galun, Ronen Basri. 2020-02-25. Algebraic Characterization of Essential Matrices and Their Averaging in Multiview Settings. https://arxiv.org/abs/1904.02663

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