Papers › Multiple Anchor Learning for Visual Object Detection

Multiple Anchor Learning for Visual Object Detection

4 Dec 2019CVPR 2020 6arXiv:1912.02252archive 2025-07-28

Wei Ke, Tianliang Zhang, Zeyi Huang, Qixiang Ye, Jianzhuang Liu, Dong Huang

Classification and localization are two pillars of visual object detectors. However, in CNN-based detectors, these two modules are usually optimized under a fixed set of candidate (or anchor) bounding boxes. This configuration significantly limits the possibility to jointly optimize classification and localization. In this paper, we propose a Multiple Instance Learning (MIL) approach that selects anchors and jointly optimizes the two modules of a CNN-based object detector. Our approach, referred to as Multiple Anchor Learning (MAL), constructs anchor bags and selects the most representative anchors from each bag. Such an iterative selection process is potentially NP-hard to optimize. To address this issue, we solve MAL by repetitively depressing the confidence of selected anchors by perturbing their corresponding features. In an adversarial selection-depression manner, MAL not only pursues optimal solutions but also fully leverages multiple anchors/features to learn a detection model. Experiments show that MAL improves the baseline RetinaNet with significant margins on the commonly used MS-COCO object detection benchmark and achieves new state-of-the-art detection performance compared with recent methods.

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KevinKecc/MAL mentioned on GitHubpytorch report
DeLightCMU/MAL pytorchMIT report
DeLightCMU/MAL-inference pytorchBSD-2-Clause report

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smooth_l1_loss DeLightCMU/MAL/maskrcnn_benchmark/layers/smooth_l1_loss.py community (archive-listed) ran MIT (permissive) · e261fa29066b37e5 · report
box2delta DeLightCMU/MAL-inference/retinanet/box.py community (archive-listed) unverified BSD-2-Clause (permissive) · 6693e538e48a84c9 · report
build_resnet_backbone DeLightCMU/MAL-inference/retinanet/backbones/backbone.py community (archive-listed) unverified BSD-2-Clause (permissive) · 661727cf46a893a5 · report
build_resnet_fpn_backbone DeLightCMU/MAL-inference/retinanet/backbones/backbone.py community (archive-listed) unverified BSD-2-Clause (permissive) · b8551d861a720f33 · report
build_resnet_fpn_p3p7_backbone DeLightCMU/MAL-inference/retinanet/backbones/backbone.py community (archive-listed) unverified BSD-2-Clause (permissive) · 81c87c9068bdbd50 · report
convert_fixedbn_model DeLightCMU/MAL-inference/retinanet/backbones/layers.py community (archive-listed) unverified BSD-2-Clause (permissive) · 333799a2d6f1a170 · report
delta2box1 DeLightCMU/MAL-inference/retinanet/box.py community (archive-listed) unverified BSD-2-Clause (permissive) · 7e0127e0e305eb71 · report
generate_anchors DeLightCMU/MAL-inference/retinanet/box.py community (archive-listed) unverified BSD-2-Clause (permissive) · df48fc695a8a624c · report
interpolate DeLightCMU/MAL/maskrcnn_benchmark/layers/misc.py community (archive-listed) unverified MIT (permissive) · 2902bf4410253ff7 · report
show_detections DeLightCMU/MAL-inference/retinanet/utils.py community (archive-listed) unverified BSD-2-Clause (permissive) · deef1b581ac0b1ec · report

Tasks

General ClassificationMultiple Instance LearningObjectObject Detectionobject-detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Object Detection COCO test-dev MAL (ResNeXt101, multi-scale) box mAP 47.0 #122 of 225 Archive leaderboard report
Object Detection COCO test-dev MAL (ResNeXt101, single-scale) box mAP 45.9 #135 of 225 Archive leaderboard report
Object Detection COCO test-dev MAL (ResNet50, single-scale) box mAP 39.2 #207 of 225 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.

Methods

1x1 ConvolutionConvolutionFPNFocal LossRetinaNet

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