Papers › Pointly-Supervised Instance Segmentation

Pointly-Supervised Instance Segmentation

13 Apr 2021CVPR 2022 1arXiv:2104.06404archive 2025-07-28

Bowen Cheng, Omkar Parkhi, Alexander Kirillov

We propose an embarrassingly simple point annotation scheme to collect weak supervision for instance segmentation. In addition to bounding boxes, we collect binary labels for a set of points uniformly sampled inside each bounding box. We show that the existing instance segmentation models developed for full mask supervision can be seamlessly trained with point-based supervision collected via our scheme. Remarkably, Mask R-CNN trained on COCO, PASCAL VOC, Cityscapes, and LVIS with only 10 annotated random points per object achieves 94%--98% of its fully-supervised performance, setting a strong baseline for weakly-supervised instance segmentation. The new point annotation scheme is approximately 5 times faster than annotating full object masks, making high-quality instance segmentation more accessible in practice. Inspired by the point-based annotation form, we propose a modification to PointRend instance segmentation module. For each object, the new architecture, called Implicit PointRend, generates parameters for a function that makes the final point-level mask prediction. Implicit PointRend is more straightforward and uses a single point-level mask loss. Our experiments show that the new module is more suitable for the point-based supervision.

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serenos/lwsis mentioned on GitHubpytorchNOASSERTION report
serenos/nuinsseg mentioned on GitHub report

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Tasks

Instance SegmentationObjectSegmentationSemantic SegmentationWeakly-supervised instance segmentation

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Methods

ConvolutionDense ConnectionsFeedforward NetworkImplicit PointRendMask R-CNNPointRendRPNRoIAlignSoftmax

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