Aerial Lifting: Neural Urban Semantic and Building Instance Lifting from Aerial Imagery

Yuqi Zhang; Guanying Chen; Jiaxing Chen; Shuguang Cui

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arXiv · 2403.11812

Aerial Lifting: Neural Urban Semantic and Building Instance Lifting from Aerial Imagery

Yuqi Zhang·Guanying Chen·Jiaxing Chen·Shuguang Cui

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Abstract

We present a neural radiance field method for urban-scale semantic and building-level instance segmentation from aerial images by lifting noisy 2D labels to 3D. This is a challenging problem due to two primary reasons. Firstly, objects in urban aerial images exhibit substantial variations in size, including buildings, cars, and roads, which pose a significant challenge for accurate 2D segmentation. Secondly, the 2D labels generated by existing segmentation methods suffer from the multi-view inconsistency problem, especially in the case of aerial images, where each image captures only a small portion of the entire scene. To overcome these limitations, we first introduce a scale-adaptive semantic label fusion strategy that enhances the segmentation of objects of varying sizes by combining labels predicted from different altitudes, harnessing the novel-view synthesis capabilities of NeRF. We then introduce a novel cross-view instance label grouping strategy based on the 3D scene representation to mitigate the multi-view inconsistency problem in the 2D instance labels. Furthermore, we exploit multi-view reconstructed depth priors to improve the geometric quality of the reconstructed radiance field, resulting in enhanced segmentation results. Experiments on multiple real-world urban-scale datasets demonstrate that our approach outperforms existing methods, highlighting its effectiveness.

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Yuqi Zhang, Guanying Chen, Jiaxing Chen, Shuguang Cui. 2024-03-18. Aerial Lifting: Neural Urban Semantic and Building Instance Lifting from Aerial Imagery. https://arxiv.org/abs/2403.11812

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