Geometry-Constrained Monocular Scale Estimation Using Semantic Segmentation for Dynamic Scenes

Hui Zhang; Zhiyang Wu; Qianqian Shangguan; Kang An

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arXiv · 2503.04235

Geometry-Constrained Monocular Scale Estimation Using Semantic Segmentation for Dynamic Scenes

Hui Zhang·Zhiyang Wu·Qianqian Shangguan·Kang An

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Abstract

Monocular visual localization plays a pivotal role in advanced driver assistance systems and autonomous driving by estimating a vehicle's ego-motion from a single pinhole camera. Nevertheless, conventional monocular visual odometry encoun-ters challenges in scale estimation due to the absence of depth information during projection. Previous methodologies, whether rooted in physical constraints or deep learning paradigms, con-tend with issues related to computational complexity and the management of dynamic objects. This study extends our prior research, presenting innovative strategies for ego-motion estima-tion and the selection of ground points. Striving for a nuanced equilibrium between computational efficiency and precision, we propose a hybrid method that leverages the SegNeXt model for real-time applications, encompassing both ego-motion estimation and ground point selection. Our methodology incorporates dy-namic object masks to eliminate unstable features and employs ground plane masks for meticulous triangulation. Furthermore, we exploit Geometry-constraint to delineate road regions for scale recovery. The integration of this approach with the mo-nocular version of ORB-SLAM3 culminates in the accurate esti-mation of a road model, a pivotal component in our scale recov-ery process. Rigorous experiments, conducted on the KITTI da-taset, systematically compare our method with existing monocu-lar visual odometry algorithms and contemporary scale recovery methodologies. The results undeniably confirm the superior ef-fectiveness of our approach, surpassing state-of-the-art visual odometry algorithms. Our source code is available at https://git hub.com/bFr0zNq/MVOSegScale.

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Hui Zhang, Zhiyang Wu, Qianqian Shangguan, Kang An. 2025-03-06. Geometry-Constrained Monocular Scale Estimation Using Semantic Segmentation for Dynamic Scenes. https://arxiv.org/abs/2503.04235

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