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arXiv · 2405.14824

Camera Relocalization in Shadow-free Neural Radiance Fields

Shiyao Xu·Caiyun Liu·Yuantao Chen·Zhenxin Zhu·Zike Yan·Yongliang Shi·Hao Zhao·Guyue Zhou
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Abstract

Camera relocalization is a crucial problem in computer vision and robotics. Recent advancements in neural radiance fields (NeRFs) have shown promise in synthesizing photo-realistic images. Several works have utilized NeRFs for refining camera poses, but they do not account for lighting changes that can affect scene appearance and shadow regions, causing a degraded pose optimization process. In this paper, we propose a two-staged pipeline that normalizes images with varying lighting and shadow conditions to improve camera relocalization. We implement our scene representation upon a hash-encoded NeRF which significantly boosts up the pose optimization process. To account for the noisy image gradient computing problem in grid-based NeRFs, we further propose a re-devised truncated dynamic low-pass filter (TDLF) and a numerical gradient averaging technique to smoothen the process. Experimental results on several datasets with varying lighting conditions demonstrate that our method achieves state-of-the-art results in camera relocalization under varying lighting conditions. Code and data will be made publicly available.

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Shiyao Xu, Caiyun Liu, Yuantao Chen, Zhenxin Zhu, Zike Yan, Yongliang Shi, Hao Zhao, Guyue Zhou. 2024-05-23. Camera Relocalization in Shadow-free Neural Radiance Fields. https://arxiv.org/abs/2405.14824

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