arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2204.04752cs.CV
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超越交叉视角的图像检索:利用卫星图像的高精度车辆定位

Beyond Cross-view Image Retrieval: Highly Accurate Vehicle Localization Using Satellite Image

The Australian National University(澳大利亚国立大学)

Yujiao Shi, Hongdong Li

摘要:

研究了地面影像与俯视卫星地图的匹配问题,提出了一种基于地面影像和俯视卫星地图的车载摄像机定位方法。现有方法通常将此问题视为跨视图图像检索,并使用学习的深度特征将地面查询图像与卫星地图的分区(例如,小块)相匹配。通过这些方法,定位精度受到卫星地图分区密度的限制(通常为数十米量级)。从传统的图像检索的智慧出发,本文提出了一种新的解决方案,可以实现高精度定位。其核心思想是将任务表述为姿态估计,并通过基于神经网络的优化来解决。具体而言,我们设计了一个两个分支{CNN},分别从地面和卫星图像中提取鲁棒的功能。为了弥合巨大的跨视图域差距,我们诉诸于几何投影模块,该模块基于相对相机姿势将卫星地图的特征投影到地面视图。为了最小化投影特征和观察特征之间的差异,我们采用可微Levenberg-Marquardt({LM})模块来迭代地搜索最佳相机姿态。整个管道是可区分的,并且端到端地运行。在标准自主车辆定位数据集上的大量实验证实了所提出方法的优越性。值得注意的是,从40 m x 40 m宽区域内的相机位置的粗略估计开始,我们的方法以80%的可能性在新的KITTI交叉视图数据集上快速将横向位置误差降低到5 m以内。

英文摘要:

This paper addresses the problem of vehicle-mounted camera localization by matching a ground-level image with an overhead-view satellite map. Existing methods often treat this problem as cross-view image retrieval, and use learned deep features to match the ground-level query image to a partition (eg, a small patch) of the satellite map. By these methods, the localization accuracy is limited by the partitioning density of the satellite map (often in the order of tens meters). Departing from the conventional wisdom of image retrieval, this paper presents a novel solution that can achieve highly-accurate localization. The key idea is to formulate the task as pose estimation and solve it by neural-net based optimization. Specifically, we design a two-branch {CNN} to extract robust features from the ground and satellite images, respectively. To bridge the vast cross-view domain gap, we resort to a Geometry Projection module that projects features from the satellite map to the ground-view, based on a relative camera pose. Aiming to minimize the differences between the projected features and the observed features, we employ a differentiable Levenberg-Marquardt ({LM}) module to search for the optimal camera pose iteratively. The entire pipeline is differentiable and runs end-to-end. Extensive experiments on standard autonomous vehicle localization datasets have confirmed the superiority of the proposed method. Notably, e.g., starting from a coarse estimate of camera location within a wide region of 40m x 40m, with an 80% likelihood our method quickly reduces the lateral location error to be within 5m on a new KITTI cross-view dataset.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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