Papers › Objects are Different: Flexible Monocular 3D Object Detection

Objects are Different: Flexible Monocular 3D Object Detection

6 Apr 2021CVPR 2021 1arXiv:2104.02323archive 2025-07-28

Yunpeng Zhang, Jiwen Lu, Jie zhou

The precise localization of 3D objects from a single image without depth information is a highly challenging problem. Most existing methods adopt the same approach for all objects regardless of their diverse distributions, leading to limited performance for truncated objects. In this paper, we propose a flexible framework for monocular 3D object detection which explicitly decouples the truncated objects and adaptively combines multiple approaches for object depth estimation. Specifically, we decouple the edge of the feature map for predicting long-tail truncated objects so that the optimization of normal objects is not influenced. Furthermore, we formulate the object depth estimation as an uncertainty-guided ensemble of directly regressed object depth and solved depths from different groups of keypoints. Experiments demonstrate that our method outperforms the state-of-the-art method by relatively 27% for the moderate level and 30% for the hard level in the test set of KITTI benchmark while maintaining real-time efficiency. Code will be available at \url{https://github.com/zhangyp15/MonoFlex}.

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zhangyp15/MonoFlex officialmentioned in paperpytorchMIT report
yanglei18/mix-teaching mentioned on GitHubpytorchApache-2.0 report

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cat zhangyp15/MonoFlex/model/utils.py official repository ran · fixture could not drive it MIT (permissive) · 6cbf46794989b731 · report
strip_prefix_if_present zhangyp15/MonoFlex/utils/model_serialization.py official repository ran · our draft was wrong MIT (permissive) · 5a951495ac113177 · report
affine_transform zhangyp15/MonoFlex/model/heatmap_coder.py official repository unverified MIT (permissive) · 65a16c264996059d · report
gaussian_radius zhangyp15/MonoFlex/model/heatmap_coder.py official repository unverified MIT (permissive) · c044d44b5a7087e4 · report
get_transfrom_matrix zhangyp15/MonoFlex/model/heatmap_coder.py official repository unverified MIT (permissive) · 194052ec40659a42 · report
ClipBoxes Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran fingerprinted Apache-2.0 (permissive) · 570e350e7fe7526b · report
IoULoss Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran fingerprinted Apache-2.0 (permissive) · c5197ebb950e466e · report
MonoFlexHead Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran fingerprinted Apache-2.0 (permissive) · 8e7a3c3289cb3e80 · report
_nms Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 59022d9630576578 · report
boxes3d_to_bev_torch Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · af38ff2bb862b433 · report
compute_bin_loss Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 65d7a40d70c53ed9 · report
compute_res_loss Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 7df13fb9e54d592b · report
decode_depth_from_keypoints Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran · our draft was wrong Apache-2.0 (permissive) · 74be68131587e23b · report
decode_depth_inv_sigmoid Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 4bf22db9eaf70901 · report
KM3DHead Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) unverified Apache-2.0 (permissive) · 7b2125261c5b536d · report
Position_loss Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) unverified Apache-2.0 (permissive) · 8469c42e1fc712db · report
_topk_channel Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) unverified Apache-2.0 (permissive) · 03b36f268d8645d0 · report
boxes_iou3d_gpu Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) unverified Apache-2.0 (permissive) · a7fa48606189776e · report
compute_rot_loss Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) unverified Apache-2.0 (permissive) · 9d749234d255406c · report
gen_position Owen-Liuyuxuan/visualDet3D/visualDet3D/networks/heads/monoflex_head.py community (archive-listed) unverified Apache-2.0 (permissive) · dae0c091d06a2048 · report

Tasks

3D Object DetectionDepth EstimationMonocular 3D Object DetectionObjectObject Detectionobject-detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Monocular 3D Object Detection KITTI Cars Moderate MonoFLEX AP Medium 13.89 #9 of 29 Archive leaderboard report

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