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arXiv · 2410.17997

Characterization of the multiplicity of solutions for camera pose given two vertically-aligned landmarks and accelerometer

Alexander R. Pruss
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Abstract

We consider the problem of recovering the position and orientation of a camera equipped with an accelerometer from sensor images of two labeled landmarks whose positions in a coordinate system aligned in a known way with gravity are known. This a variant on the much studied P$n$P problem of recovering camera position and orientation from $n$ points without any gravitational data. It is proved that in three types of singular cases there are infinitely many solutions, in another type of case there is one, and in a final type of case there are two. A precise characterization of each type of case. In particular, there is always a unique solution in the practically interesting case where the two landmarks are at the same altitude and the camera is at a different altitude. This case is studied by numerical simulation and an implementation on a consumer cellphone. It is also proved that if the two landmarks are unlabeled, then apart from the same singular cases, there are still always one or two solutions.

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Alexander R. Pruss. 2024-10-23. Characterization of the multiplicity of solutions for camera pose given two vertically-aligned landmarks and accelerometer. https://arxiv.org/abs/2410.17997

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