Papers › LiDAR2Map: In Defense of LiDAR-Based Semantic Map Construction Using Online Camera Distillation

LiDAR2Map: In Defense of LiDAR-Based Semantic Map Construction Using Online Camera Distillation

22 Apr 2023CVPR 2023 1arXiv:2304.11379archive 2025-07-28

Song Wang, Wentong Li, Wenyu Liu, Xiaolu Liu, Jianke Zhu

Semantic map construction under bird's-eye view (BEV) plays an essential role in autonomous driving. In contrast to camera image, LiDAR provides the accurate 3D observations to project the captured 3D features onto BEV space inherently. However, the vanilla LiDAR-based BEV feature often contains many indefinite noises, where the spatial features have little texture and semantic cues. In this paper, we propose an effective LiDAR-based method to build semantic map. Specifically, we introduce a BEV feature pyramid decoder that learns the robust multi-scale BEV features for semantic map construction, which greatly boosts the accuracy of the LiDAR-based method. To mitigate the defects caused by lacking semantic cues in LiDAR data, we present an online Camera-to-LiDAR distillation scheme to facilitate the semantic learning from image to point cloud. Our distillation scheme consists of feature-level and logit-level distillation to absorb the semantic information from camera in BEV. The experimental results on challenging nuScenes dataset demonstrate the efficacy of our proposed LiDAR2Map on semantic map construction, which significantly outperforms the previous LiDAR-based methods over 27.9% mIoU and even performs better than the state-of-the-art camera-based approaches. Source code is available at: https://github.com/songw-zju/LiDAR2Map.

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gen_dx_bx songw-zju/LiDAR2Map/map/model/camera/lift_splat.py official repository ran MIT (permissive) · 044c907ab4e72406 · report
get_batch_iou songw-zju/LiDAR2Map/map/evaluation/iou.py official repository ran · honoured contract fingerprinted MIT (permissive) · 41b5eb6eb54f33c6 · report
isnan songw-zju/LiDAR2Map/map/model/loss/Lovasz_Softmax.py official repository ran · violated contract fingerprinted MIT (permissive) · 5f4f4355be28c01e · report
lovasz_grad songw-zju/LiDAR2Map/map/model/loss/Lovasz_Softmax.py official repository ran · violated contract fingerprinted MIT (permissive) · e85b5d21dc5b8382 · report
mean songw-zju/LiDAR2Map/map/model/loss/Lovasz_Softmax.py official repository ran · fixture could not drive it MIT (permissive) · 80b5a150c6e092f7 · report
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chamfer_distance songw-zju/LiDAR2Map/map/evaluation/chamfer_distance.py official repository unverified MIT (permissive) · bd2738dcfbe8cea9 · report
compute_feature_distill_loss songw-zju/LiDAR2Map/map/model/lidar/lidar2map.py official repository unverified MIT (permissive) · bd67c2b7e9187e9e · report
compute_logit_distill_loss songw-zju/LiDAR2Map/map/model/lidar/lidar2map.py official repository unverified MIT (permissive) · 61a17a6e6d49f4a6 · report
get_line_instances_from_mask songw-zju/LiDAR2Map/map/evaluation/AP.py official repository unverified MIT (permissive) · 49ae2a43e69a170b · report
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onehot_encoding_spread songw-zju/LiDAR2Map/map/evaluation/angle_diff.py official repository unverified MIT (permissive) · a6160ebc538f6782 · report
pad_or_trim_to_np songw-zju/LiDAR2Map/map/model/lidar/voxel.py official repository unverified MIT (permissive) · 46216e92d8b10f17 · report
raval_index songw-zju/LiDAR2Map/map/model/lidar/voxel.py official repository unverified MIT (permissive) · 926958e17016ee77 · report
semantic_mask_chamfer_dist_cum songw-zju/LiDAR2Map/map/evaluation/chamfer_distance.py official repository unverified MIT (permissive) · 49b1b7956f5e59b1 · report
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