OrthoLoC: UAV 6-DoF Localization and Calibration Using Orthographic Geodata

1 DeepScenario     2 TUM     3 MCML

OrthoLoC is a framework for UAV camera localization and calibration using orthographic geodata. The project provides a large-scale benchmark dataset and implementation of algorithms for matching, localization, and calibration of UAV imagery using orthophotos (DOPs) and digital surface models (DSMs).

Abstract

Accurate visual localization from aerial views is a fundamental problem with applications in mapping, large-area inspection, and search-and-rescue operations. In many scenarios, these systems require high-precision localization while operating with limited resources (e.g., no internet connection or GNSS/GPS support), making large image databases or heavy 3D models impractical. Surprisingly, little attention has been given to leveraging orthographic geodata as an alternative paradigm, which is lightweight and increasingly available through free releases by governmental authorities (e.g., the European Union).

To fill this gap, we propose OrthoLoC, the first large-scale dataset comprising 16,425 UAV images from Germany and the United States with multiple modalities. The dataset addresses domain shifts between UAV imagery and geospatial data. Its paired structure enables fair benchmarking of existing solutions by decoupling image retrieval from feature matching, allowing isolated evaluation of localization and calibration performance. Through comprehensive evaluation, we examine the impact of domain shifts, data resolutions, and covisibility on localization accuracy. Finally, we introduce a refinement technique called AdHoP, which can be integrated with any feature matcher, improving matching by up to 95% and reducing translation error by up to 63%.

The OrthoLoC Dataset

Samples
Overview of our dataset: We show the UAV query images, the corresponding point maps represented as depth maps, the orthophotos (DOPs), and the digital surface models (DSMs) represented as elevation maps.

Description

OrthoLoC is a comprehensive UAV localization dataset that addresses key limitations in existing benchmarks. Our dataset comprises 16.4k real UAV images spanning 47 locations across 19 regions in Germany and the United States, captured in diverse environmental contexts including urban, suburban, industrial, rural, and highway scenes. Each sample provides a query image with precise ground-truth 6-DoF pose, camera intrinsics, and rich 3D scene representations: point maps, 3D keypoints, local meshes, and aligned 2.5D geodata rasters derived from multiple sources.

Download

  • Download the dataset from here
  • Size: 287.3GB

License

The OrthoLoC dataset is licensed under CC BY-NC-SA 4.0
Geodata used for augmenting the dataset to close the gap of cross-domain are issued from multiple open geoportals in Europe which have the CC BY 4.0 license. Please consult the following list for the specific license of the data used in this dataset:

Visualizations

Data Modalities

OrthoLoC Sample Modalities

Meshes

Press G to toggle wireframe. Press R to reset view.

Vision-Geometry Duality

Query vs. Point Map (visualized as depth map)

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DOP vs. DSM

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Cross Domain Data Alignment

Our dataset demonstrates precise alignment of geodata from diverse sources, including 3D photogrammetry reconstructions and open geoportal downloads. This crucial capability enables superior localization and calibration performance — a feature notably absent in datasets like AnyVisLoc.


DOP vs xDOP

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DSM vs xDSM

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Acknowledgements

BibTeX

@inproceedings{dhaouadi2025ortholoc,
  title        = {OrthoLoC: UAV 6-DoF Localization and Calibration Using Orthographic Geodata},
  author       = {Dhaouadi, Oussema and Marin Riccardo and Meier, Johannes and Kaiser, Jacques and Cremers, Daniel},
  booktitle    = {(under review)},
  year         = {2025},
}