Papers › Group-Free 3D Object Detection via Transformers

Group-Free 3D Object Detection via Transformers

1 Apr 2021ICCV 2021 10arXiv:2104.00678archive 2025-07-28

Ze Liu, Zheng Zhang, Yue Cao, Han Hu, Xin Tong

Recently, directly detecting 3D objects from 3D point clouds has received increasing attention. To extract object representation from an irregular point cloud, existing methods usually take a point grouping step to assign the points to an object candidate so that a PointNet-like network could be used to derive object features from the grouped points. However, the inaccurate point assignments caused by the hand-crafted grouping scheme decrease the performance of 3D object detection. In this paper, we present a simple yet effective method for directly detecting 3D objects from the 3D point cloud. Instead of grouping local points to each object candidate, our method computes the feature of an object from all the points in the point cloud with the help of an attention mechanism in the Transformers \cite{vaswani2017attention}, where the contribution of each point is automatically learned in the network training. With an improved attention stacking scheme, our method fuses object features in different stages and generates more accurate object detection results. With few bells and whistles, the proposed method achieves state-of-the-art 3D object detection performance on two widely used benchmarks, ScanNet V2 and SUN RGB-D. The code and models are publicly available at \url{https://github.com/zeliu98/Group-Free-3D}

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zeliu98/Group-Free-3D officialmentioned in papermentioned on GitHubpytorch report
KookHoiKim/GroupFree3dBaseline mentioned on GitHubpytorch report
tyolm/groupfree3d_mindspore mentioned on GitHubmindspore report

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GroupFreeDetector zeliu98/Group-Free-3D/models/detector.py official repository unverified MIT (permissive) · ddd521a89f668ed8 · report
Pointnet2Backbone zeliu98/Group-Free-3D/models/detector.py official repository unverified MIT (permissive) · b3d2771d692667b7 · report
ClsAgnosticPredictHead KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran · metamorphic tier: deterministic MIT (permissive) · 1032f9a2b7eee988 · report
FPSModule KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran · metamorphic tier: deterministic MIT (permissive) · 5a05b2fc118b751f · report
PointnetFPModule KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran · metamorphic tier: deterministic MIT (permissive) · d53ad68b74734b36 · report
PointsObjClsModule KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran · metamorphic tier: deterministic fingerprinted MIT (permissive) · 8a069336f892a257 · report
PositionEmbeddingLearned KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran · metamorphic tier: deterministic MIT (permissive) · 490c93aa45d7780a · report
PredictHead KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran MIT (permissive) · e0691173a4ce4a26 · report
ThreeInterpolate KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran MIT (permissive) · 565863bfed9f02fc · report
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multi_head_attention_forward KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) ran · fixture could not drive it MIT (permissive) · 89a5e4ca75931eac · report
GeneralSamplingModule KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) unverified MIT (permissive) · ba5e770e929c3505 · report
GroupFreeDetector KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) unverified MIT (permissive) · 8a951c82c3d19407 · report
MultiheadAttention KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) unverified MIT (permissive) · 6bd1a32eae6a6a53 · report
Pointnet2Backbone KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) unverified MIT (permissive) · dba99ebc3fa7f7a2 · report
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TransformerDecoderLayer KookHoiKim/GroupFree3dBaseline/models/detector.py community (archive-listed) unverified MIT (permissive) · 582548d08ea83826 · report

Tasks

3D Object DetectionObjectObject Detectionobject-detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
3D Object Detection SUN-RGBD GroupFree3D mAP@0.25 63.0 #4 of 8 Archive leaderboard report
3D Object Detection SUN-RGBD GroupFree3D mAP@0.5 45.2 #4 of 8 Archive leaderboard report
3D Object Detection SUN-RGBD val GroupFree3D(Geo only) mAP@0.25 63.0 #17 of 32 Archive leaderboard report
3D Object Detection SUN-RGBD val GroupFree3D(Geo only) mAP@0.5 45.2 #17 of 32 Archive leaderboard report
3D Object Detection ScanNetV2 GroupFree3D mAP@0.25 69.1 #20 of 33 Archive leaderboard report
3D Object Detection ScanNetV2 GroupFree3D mAP@0.5 52.8 #20 of 33 Archive leaderboard report

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