Papers › Surface Representation for Point Clouds

Surface Representation for Point Clouds

11 May 2022CVPR 2022 1arXiv:2205.05740archive 2025-07-28

Haoxi Ran, Jun Liu, Chengjie Wang

Most prior work represents the shapes of point clouds by coordinates. However, it is insufficient to describe the local geometry directly. In this paper, we present \textbf{RepSurf} (representative surfaces), a novel representation of point clouds to \textbf{explicitly} depict the very local structure. We explore two variants of RepSurf, Triangular RepSurf and Umbrella RepSurf inspired by triangle meshes and umbrella curvature in computer graphics. We compute the representations of RepSurf by predefined geometric priors after surface reconstruction. RepSurf can be a plug-and-play module for most point cloud models thanks to its free collaboration with irregular points. Based on a simple baseline of PointNet++ (SSG version), Umbrella RepSurf surpasses the previous state-of-the-art by a large margin for classification, segmentation and detection on various benchmarks in terms of performance and efficiency. With an increase of around \textbf{0.008M} number of parameters, \textbf{0.04G} FLOPs, and \textbf{1.12ms} inference time, our method achieves \textbf{94.7\%} (+0.5\%) on ModelNet40, and \textbf{84.6\%} (+1.8\%) on ScanObjectNN for classification, while \textbf{74.3\%} (+0.8\%) mIoU on S3DIS 6-fold, and \textbf{70.0\%} (+1.6\%) mIoU on ScanNet for segmentation. For detection, previous state-of-the-art detector with our RepSurf obtains \textbf{71.2\%} (+2.1\%) mAP₂₅, \textbf{54.8\%} (+2.0\%) mAP₅₀ on ScanNetV2, and \textbf{64.9\%} (+1.9\%) mAP₂₅, \textbf{47.7\%} (+2.5\%) mAP₅₀ on SUN RGB-D. Our lightweight Triangular RepSurf performs its excellence on these benchmarks as well. The code is publicly available at \url{https://github.com/hancyran/RepSurf}.

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xyz2cylind hancyran/RepSurf/segmentation/modules/polar_utils.py official repository ran fingerprinted Apache-2.0 (permissive) · bdaeeb5851d70f67 · report
xyz2sphere hancyran/RepSurf/segmentation/modules/polar_utils.py official repository ran fingerprinted Apache-2.0 (permissive) · bcf83718dbe85554 · report
cal_normal hancyran/RepSurf/classification/modules/recons_utils.py official repository unverified Apache-2.0 (permissive) · 90abbae1e8a9515c · report
farthest_point_sample hancyran/RepSurf/classification/modules/pointnet2_utils.py official repository unverified Apache-2.0 (permissive) · e165142db58e96b5 · report
get_aug_args hancyran/RepSurf/classification/modules/ptaug_utils.py official repository unverified Apache-2.0 (permissive) · b6178ce69e144ce7 · report
index_points hancyran/RepSurf/classification/modules/pointnet2_utils.py official repository unverified Apache-2.0 (permissive) · 25dec942fa25547e · report
pca hancyran/RepSurf/classification/modules/recons_utils.py official repository unverified Apache-2.0 (permissive) · 43f6d0436aebc666 · report
resort_points hancyran/RepSurf/classification/modules/repsurface_utils.py official repository unverified Apache-2.0 (permissive) · ef36d757b28c9f41 · report
shift_point_cloud hancyran/RepSurf/classification/modules/ptaug_utils.py official repository unverified Apache-2.0 (permissive) · cf984792acb072ff · report
square_distance hancyran/RepSurf/classification/modules/pointnet2_utils.py official repository unverified Apache-2.0 (permissive) · 9d026e3279fe6446 · report
transform_point_cloud hancyran/RepSurf/classification/modules/ptaug_utils.py official repository unverified Apache-2.0 (permissive) · 8a2b98e6b1b0965e · report
transform_point_cloud_coord hancyran/RepSurf/segmentation/modules/aug_utils.py official repository unverified Apache-2.0 (permissive) · 6b78fa00ee2dcd42 · report
transform_point_cloud_rgb hancyran/RepSurf/segmentation/modules/aug_utils.py official repository unverified Apache-2.0 (permissive) · 1794cefb931feef6 · report
xyz2cylind hancyran/RepSurf/classification/modules/polar_utils.py official repository unverified Apache-2.0 (permissive) · ab4a32fde08cd85f · report
xyz2sphere hancyran/RepSurf/classification/modules/polar_utils.py official repository unverified Apache-2.0 (permissive) · c5f00144812c665a · report

Tasks

3D Object Detection3D Point Cloud Classification3D Semantic SegmentationSemantic SegmentationSupervised Only 3D Point Cloud ClassificationSurface Reconstruction

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
3D Object Detection SUN-RGBD val RepSurf-U mAP@0.25 64.9 #13 of 32 Archive leaderboard report
3D Object Detection SUN-RGBD val RepSurf-U mAP@0.5 47.7 #13 of 32 Archive leaderboard report
3D Object Detection ScanNetV2 RepSurf-U mAP@0.25 71.2 #18 of 33 Archive leaderboard report
3D Object Detection ScanNetV2 RepSurf-U mAP@0.5 54.8 #18 of 33 Archive leaderboard report
3D Point Cloud Classification ModelNet40 RepSurf-U FLOPs 0.81G #9 of 111 Archive leaderboard report
3D Point Cloud Classification ModelNet40 RepSurf-U Number of params 1.48M #9 of 111 Archive leaderboard report
3D Point Cloud Classification ModelNet40 RepSurf-U Overall Accuracy 94.7 #9 of 111 Archive leaderboard report
3D Point Cloud Classification ScanObjectNN RepSurf-U (2x) FLOPs 2.43G #52 of 77 Archive leaderboard report
3D Point Cloud Classification ScanObjectNN RepSurf-U (2x) Number of params 6.80M #52 of 77 Archive leaderboard report
3D Point Cloud Classification ScanObjectNN RepSurf-U (2x) Overall Accuracy 86.0 #52 of 77 Archive leaderboard report
3D Point Cloud Classification ScanObjectNN RepSurf-U FLOPs 0.81G #58 of 77 Archive leaderboard report
3D Point Cloud Classification ScanObjectNN RepSurf-U Number of params 1.48M #58 of 77 Archive leaderboard report
3D Point Cloud Classification ScanObjectNN RepSurf-U Overall Accuracy 84.6 #58 of 77 Archive leaderboard report
Semantic Segmentation S3DIS RepSurf-U FLOPs 1.04G #14 of 54 Archive leaderboard report
Semantic Segmentation S3DIS RepSurf-U Mean IoU 74.3 #14 of 54 Archive leaderboard report
Semantic Segmentation S3DIS RepSurf-U Number of params 0.97M #14 of 54 Archive leaderboard report
Semantic Segmentation S3DIS RepSurf-U Params (M) 0.97 #14 of 54 Archive leaderboard report
Semantic Segmentation S3DIS RepSurf-U mAcc 82.6 #14 of 54 Archive leaderboard report
Semantic Segmentation S3DIS RepSurf-U oAcc 90.8 #14 of 54 Archive leaderboard report
Semantic Segmentation S3DIS Area5 RepSurf-U FLOPs 1.04G #36 of 61 Archive leaderboard report
Semantic Segmentation S3DIS Area5 RepSurf-U Number of params 0.97M #36 of 61 Archive leaderboard report
Semantic Segmentation S3DIS Area5 RepSurf-U mAcc 76.0 #36 of 61 Archive leaderboard report
Semantic Segmentation S3DIS Area5 RepSurf-U mIoU 68.9 #36 of 61 Archive leaderboard report
Semantic Segmentation S3DIS Area5 RepSurf-U oAcc 90.2 #36 of 61 Archive leaderboard report

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