Papers › UniMatch V2: Pushing the Limit of Semi-Supervised Semantic Segmentation

UniMatch V2: Pushing the Limit of Semi-Supervised Semantic Segmentation

14 Oct 2024arXiv:2410.10777archive 2025-07-28

Lihe Yang, Zhen Zhao, Hengshuang Zhao

Semi-supervised semantic segmentation (SSS) aims at learning rich visual knowledge from cheap unlabeled images to enhance semantic segmentation capability. Among recent works, UniMatch improves its precedents tremendously by amplifying the practice of weak-to-strong consistency regularization. Subsequent works typically follow similar pipelines and propose various delicate designs. Despite the achieved progress, strangely, even in this flourishing era of numerous powerful vision models, almost all SSS works are still sticking to 1) using outdated ResNet encoders with small-scale ImageNet-1K pre-training, and 2) evaluation on simple Pascal and Cityscapes datasets. In this work, we argue that, it is necessary to switch the baseline of SSS from ResNet-based encoders to more capable ViT-based encoders (e.g., DINOv2) that are pre-trained on massive data. A simple update on the encoder (even using 2x fewer parameters) can bring more significant improvement than careful method designs. Built on this competitive baseline, we present our upgraded and simplified UniMatch V2, inheriting the core spirit of weak-to-strong consistency from V1, but requiring less training cost and providing consistently better results. Additionally, witnessing the gradually saturated performance on Pascal and Cityscapes, we appeal that we should focus on more challenging benchmarks with complex taxonomy, such as ADE20K and COCO datasets. Code, models, and logs of all reported values, are available at https://github.com/LiheYoung/UniMatch-V2.

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Tasks

Semantic SegmentationSemi-Supervised Semantic SegmentationSemi-supervised Change Detection

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Semi-Supervised Semantic Segmentation ADE20K 1/16 labeled UniMatch V2 Validation mIoU 46.7 #1 of 5 Archive leaderboard report
Semi-Supervised Semantic Segmentation ADE20K 1/32 labeled UniMatch V2 Validation mIoU 45.0 #1 of 5 Archive leaderboard report
Semi-Supervised Semantic Segmentation COCO 1/128 labeled UniMatch V2 Validation mIoU 58.7 #1 of 9 Archive leaderboard report
Semi-Supervised Semantic Segmentation COCO 1/256 labeled UniMatch V2 Validation mIoU 55.8 #1 of 9 Archive leaderboard report
Semi-Supervised Semantic Segmentation COCO 1/32 labeled UniMatch V2 Validation mIoU 63.3 #1 of 7 Archive leaderboard report
Semi-Supervised Semantic Segmentation COCO 1/512 labeled UniMatch V2 Validation mIoU 47.9 #2 of 8 Archive leaderboard report
Semi-Supervised Semantic Segmentation COCO 1/64 labeled UniMatch V2 Validation mIoU 60.4 #1 of 9 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 12.5% labeled UniMatch V2 (DINOv2-B) Validation mIoU 84.3% #1 of 33 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 25% labeled UniMatch V2 (DINOv2-B) Validation mIoU 84.5% #1 of 30 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 50% labeled UniMatch V2 (DINOv2-B) Validation mIoU 85.1% #1 of 23 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 6.25% labeled UniMatch V2 (DINOv2-B) Validation mIoU 83.6 #1 of 18 Archive leaderboard report
Semi-Supervised Semantic Segmentation PASCAL VOC 2012 1464 labels UniMatch V2 (DINOv2-B) Validation mIoU 90.8 #1 of 17 Archive leaderboard report
Semi-Supervised Semantic Segmentation PASCAL VOC 2012 183 labeled UniMatch V2 (DINOv2-B) Validation mIoU 87.9 #1 of 16 Archive leaderboard report
Semi-Supervised Semantic Segmentation PASCAL VOC 2012 366 labeled UniMatch V2 (DINOv2-B) Validation mIoU 88.9 #1 of 15 Archive leaderboard report
Semi-Supervised Semantic Segmentation PASCAL VOC 2012 732 labeled UniMatch V2 (DINOv2-B) Validation mIoU 90.0 #1 of 16 Archive leaderboard report
Semi-Supervised Semantic Segmentation PASCAL VOC 2012 92 labeled UniMatch V2 (DINOv2-B) Validation mIoU 86.3 #2 of 17 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 10% labeled data UniMatch V2 IoU 83.8 #1 of 5 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 10% labeled data UniMatch V2 OA 99.11 #1 of 5 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 20% labeled data UniMatch V2 IoU 84.3 #1 of 4 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 20% labeled data UniMatch V2 OA 99.14 #1 of 4 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 40% labeled data UniMatch V2 IoU 84.3 #2 of 4 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 40% labeled data UniMatch V2 OA 99.14 #2 of 4 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 5% labeled data UniMatch V2 IoU 83.3 #1 of 5 Archive leaderboard report
Semi-supervised Change Detection LEVIR-CD - 5% labeled data UniMatch V2 OA 99.08 #1 of 5 Archive leaderboard report
Semi-supervised Change Detection WHU - 20% labeled data UniMatch V2 IoU 87.9 #1 of 4 Archive leaderboard report
Semi-supervised Change Detection WHU - 20% labeled data UniMatch V2 OA 99.50 #1 of 4 Archive leaderboard report
Semi-supervised Change Detection WHU - 40% labeled data UniMatch V2 IoU 88.6 #1 of 4 Archive leaderboard report
Semi-supervised Change Detection WHU - 40% labeled data UniMatch V2 OA 99.52 #1 of 4 Archive leaderboard report

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Methods

Average PoolingConvolutionFocusGlobal Average PoolingKaiming InitializationMax Pooling

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