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arXiv · 2410.14164

Optimal DLT-based Solutions for the Perspective-n-Point

Sébastien Henry·John A. Christian
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Abstract

We propose a modified normalized direct linear transform (DLT) algorithm for solving the perspective-n-point (PnP) problem with much better behavior than the conventional DLT. The modification consists of analytically weighting the different measurements in the linear system with a negligible increase in computational load. Our approach exhibits clear improvements -- in both performance and runtime -- when compared to popular methods such as EPnP, CPnP, RPnP, and OPnP. Our new non-iterative solution approaches that of the true optimal found via Gauss-Newton optimization, but at a fraction of the computational cost. Our optimal DLT (oDLT) implementation, as well as the experiments, are released in open source.

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Sébastien Henry, John A. Christian. 2024-10-18. Optimal DLT-based Solutions for the Perspective-n-Point. https://arxiv.org/abs/2410.14164

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