Papers › Distribution Alignment: A Unified Framework for Long-tail Visual Recognition

Distribution Alignment: A Unified Framework for Long-tail Visual Recognition

30 Mar 2021CVPR 2021 1arXiv:2103.16370archive 2025-07-28

Songyang Zhang, Zeming Li, Shipeng Yan, Xuming He, Jian Sun

Despite the recent success of deep neural networks, it remains challenging to effectively model the long-tail class distribution in visual recognition tasks. To address this problem, we first investigate the performance bottleneck of the two-stage learning framework via ablative study. Motivated by our discovery, we propose a unified distribution alignment strategy for long-tail visual recognition. Specifically, we develop an adaptive calibration function that enables us to adjust the classification scores for each data point. We then introduce a generalized re-weight method in the two-stage learning to balance the class prior, which provides a flexible and unified solution to diverse scenarios in visual recognition tasks. We validate our method by extensive experiments on four tasks, including image classification, semantic segmentation, object detection, and instance segmentation. Our approach achieves the state-of-the-art results across all four recognition tasks with a simple and unified framework. The code and models will be made publicly available at: https://github.com/Megvii-BaseDetection/DisAlign

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build_roi_heads Megvii-BaseDetection/DisAlign/instance_seg/lvis0.5/mask_rcnn/res50/mask_rcnn.res50.fpn.lvis.multiscale.cos_norm.disalign.1x/net.py official repository unverified Apache-2.0 recorded; this copy not marked cleared · pointer only · 430a3a654e81b1db · report
check_checkpoint Megvii-BaseDetection/DisAlign/instance_seg/lvis0.5/mask_rcnn/res50/mask_rcnn.res50.fpn.lvis.multiscale.cos_norm.disalign.1x/config.py official repository unverified Apache-2.0 recorded; this copy not marked cleared · pointer only · 135c61a560b31bce · report
get_class_grw_weight Megvii-BaseDetection/DisAlign/semantic_seg/disalign/models/losses/grw_cross_entropy_loss.py official repository unverified Apache-2.0 recorded; this copy not marked cleared · pointer only · 5e8f4e5f8be47375 · report

Tasks

General ClassificationImage ClassificationInstance SegmentationLong-tail LearningObject DetectionSegmentationSemantic Segmentationimage-classificationobject-detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Long-tail Learning ImageNet-LT DisAlign Top-1 Accuracy 53.4 #43 of 69 Archive leaderboard report
Long-tail Learning Places-LT DisAlign Top-1 Accuracy 39.3 #20 of 29 Archive leaderboard report
Long-tail Learning iNaturalist 2018 DisAlign Top-1 Accuracy 70.6% #30 of 43 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.

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