Papers › Weakly-supervised Instance Segmentation via Class-agnostic Learning with Salient Images

Weakly-supervised Instance Segmentation via Class-agnostic Learning with Salient Images

4 Apr 2021CVPR 2021 1arXiv:2104.01526archive 2025-07-28

Xinggang Wang, Jiapei Feng, Bin Hu, Qi Ding, Longjin Ran, Xiaoxin Chen, Wenyu Liu

Humans have a strong class-agnostic object segmentation ability and can outline boundaries of unknown objects precisely, which motivates us to propose a box-supervised class-agnostic object segmentation (BoxCaseg) based solution for weakly-supervised instance segmentation. The BoxCaseg model is jointly trained using box-supervised images and salient images in a multi-task learning manner. The fine-annotated salient images provide class-agnostic and precise object localization guidance for box-supervised images. The object masks predicted by a pretrained BoxCaseg model are refined via a novel merged and dropped strategy as proxy ground truth to train a Mask R-CNN for weakly-supervised instance segmentation. Only using $7991$ salient images, the weakly-supervised Mask R-CNN is on par with fully-supervised Mask R-CNN on PASCAL VOC and significantly outperforms previous state-of-the-art box-supervised instance segmentation methods on COCO. The source code, pretrained models and datasets are available at \url{https://github.com/hustvl/BoxCaseg}.

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Tasks

Box-supervised Instance SegmentationInstance SegmentationMulti-Task LearningObjectObject LocalizationSegmentationSemantic SegmentationWeakly-supervised instance segmentation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Box-supervised Instance Segmentation COCO test-dev BoxCaseg mask AP 30.9 #5 of 7 Archive leaderboard report

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Methods

ConvolutionMask R-CNNRPNRoIAlignSoftmax

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