Papers › MinkLoc++: Lidar and Monocular Image Fusion for Place Recognition

MinkLoc++: Lidar and Monocular Image Fusion for Place Recognition

12 Apr 2021arXiv:2104.05327archive 2025-07-28

Jacek Komorowski, Monika Wysoczanska, Tomasz Trzcinski

We introduce a discriminative multimodal descriptor based on a pair of sensor readings: a point cloud from a LiDAR and an image from an RGB camera. Our descriptor, named MinkLoc++, can be used for place recognition, re-localization and loop closure purposes in robotics or autonomous vehicles applications. We use late fusion approach, where each modality is processed separately and fused in the final part of the processing pipeline. The proposed method achieves state-of-the-art performance on standard place recognition benchmarks. We also identify dominating modality problem when training a multimodal descriptor. The problem manifests itself when the network focuses on a modality with a larger overfit to the training data. This drives the loss down during the training but leads to suboptimal performance on the evaluation set. In this work we describe how to detect and mitigate such risk when using a deep metric learning approach to train a multimodal neural network. Our code is publicly available on the project website: https://github.com/jac99/MinkLocMultimodal.

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tensor2img jac99/MinkLocMultimodal/datasets/augmentation.py official repository ran MIT (permissive) · ffc92c5bb8278ff1 · report
image4lidar jac99/MinkLocMultimodal/datasets/oxford.py official repository unverified MIT (permissive) · a443d3b499a823b6 · report
ts_from_filename jac99/MinkLocMultimodal/datasets/oxford.py official repository unverified MIT (permissive) · 7cd8433380d56d84 · report

Tasks

3D Place RecognitionAutonomous VehiclesMetric LearningMultimodal Deep LearningVisual Place Recognition

1 archive task tag without a task page not shown.

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
3D Place Recognition CS-Campus3D Minkloc3Dv2 AR@1 67.06 #3 of 7 Archive leaderboard report
3D Place Recognition CS-Campus3D Minkloc3Dv2 AR@1 cross-source 52.46 #3 of 7 Archive leaderboard report
3D Place Recognition CS-Campus3D Minkloc3Dv2 AR@1% 76.68 #3 of 7 Archive leaderboard report
3D Place Recognition CS-Campus3D Minkloc3Dv2 AR@1% cross-source 83.48 #3 of 7 Archive leaderboard report
Visual Place Recognition Oxford RobotCar (LiDAR 4096 points+RGB) MinkLoc++ (LiDAR+RGB) recall@top1 96.7 #1 of 3 Archive leaderboard report
Visual Place Recognition Oxford RobotCar (LiDAR 4096 points+RGB) MinkLoc++ (LiDAR+RGB) recall@top1% 99.1 #1 of 3 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

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