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arXiv · 1912.09923

A Calibration Scheme for Non-Line-of-Sight Imaging Setups

Jonathan Klein·Martin Laurenzis·Matthias B. Hullin·Julian Iseringhausen
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Abstract

The recent years have given rise to a large number of techniques for "looking around corners", i.e., for reconstructing occluded objects from time-resolved measurements of indirect light reflections off a wall. While the direct view of cameras is routinely calibrated in computer vision applications, the calibration of non-line-of-sight setups has so far relied on manual measurement of the most important dimensions (device positions, wall position and orientation, etc.). In this paper, we propose a semi-automatic method for calibrating such systems that relies on mirrors as known targets. A roughly determined initialization is refined in order to optimize a spatio-temporal consistency. Our system is general enough to be applicable to a variety of sensing scenarios ranging from single sources/detectors via scanning arrangements to large-scale arrays. It is robust towards bad initialization and the achieved accuracy is proportional to the depth resolution of the camera system. We demonstrate this capability with a real-world setup and despite a large number of dead pixels and very low temporal resolution achieve a result that outperforms a manual calibration.

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Jonathan Klein, Martin Laurenzis, Matthias B. Hullin, Julian Iseringhausen. 2019-12-20. A Calibration Scheme for Non-Line-of-Sight Imaging Setups. https://doi.org/10.1364/oe.398647

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