Onsite Non-Line-of-Sight Imaging via Online Calibrations

TL;DR

This paper introduces an online calibration method for non-line-of-sight imaging systems that enables real-time adjustments without auxiliary tools, improving flexibility in dynamic scenes.

Contribution

It proposes a novel online calibration approach that decouples LOS and hidden components directly during onsite scanning, eliminating the need for pre-calibration and auxiliary calibration devices.

Findings

Supports real-time system recalibration during scanning.

Works in both laboratory and real-world environments.

Avoids auxiliary calibration tools like mirrors or checkerboards.

Abstract

There has been an increasing interest in deploying non-line-of-sight (NLOS) imaging systems for recovering objects behind an obstacle. Existing solutions generally pre-calibrate the system before scanning the hidden objects. Onsite adjustments of the occluder, object and scanning pattern require re-calibration. We present an online calibration technique that directly decouples the acquired transients at onsite scanning into the LOS and hidden components. We use the former to directly (re)calibrate the system upon changes of scene/obstacle configurations, scanning regions, and scanning patterns whereas the latter for hidden object recovery via spatial, frequency or learning based techniques. Our technique avoids using auxiliary calibration apparatus such as mirrors or checkerboards and supports both laboratory validations and real-world deployments.