Efficient Solution of Point-Line Absolute Pose

Abstract

We revisit certain problems of pose estimation based on 3D-2D correspondences between features which may be points or lines. Specifically, we address the two previously-studied minimal problems of estimating camera extrinsics from $p\in\{1,2\}$ point-point correspondences and $l=3-p$ line-line correspondences. To the best of our knowledge, all of the previously-known practical solutions to these problems required computing the roots of degree $\geq 4$ (univariate) polynomials when $p=2$, or degree $\geq 8$ polynomials when $p=1$. We describe and implement two elementary solutions which reduce the degrees of the needed polynomials from 4 to 2 and from 8 to 4, respectively. We show experimentally that the resulting solvers are numerically stable and fast: when compared to the previous state-of-the art, we may obtain nearly an order of magnitude speedup. The code is available at https://github.com/petrhruby97/efficient_absolute