Papers › ClassMix: Segmentation-Based Data Augmentation for Semi-Supervised Learning

ClassMix: Segmentation-Based Data Augmentation for Semi-Supervised Learning

15 Jul 2020arXiv:2007.07936archive 2025-07-28

Viktor Olsson, Wilhelm Tranheden, Juliano Pinto, Lennart Svensson

The state of the art in semantic segmentation is steadily increasing in performance, resulting in more precise and reliable segmentations in many different applications. However, progress is limited by the cost of generating labels for training, which sometimes requires hours of manual labor for a single image. Because of this, semi-supervised methods have been applied to this task, with varying degrees of success. A key challenge is that common augmentations used in semi-supervised classification are less effective for semantic segmentation. We propose a novel data augmentation mechanism called ClassMix, which generates augmentations by mixing unlabelled samples, by leveraging on the network's predictions for respecting object boundaries. We evaluate this augmentation technique on two common semi-supervised semantic segmentation benchmarks, showing that it attains state-of-the-art results. Lastly, we also provide extensive ablation studies comparing different design decisions and training regimes.

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color_map WilhelmT/ClassMix/evaluateSSL.py official repository ran · honoured contract fingerprinted MIT (permissive) · fcbd501f30a007d4 · report
conv3x3 WilhelmT/ClassMix/model/deeplabv2.py official repository ran · our draft was wrong MIT (permissive) · fac5364e2f53c6db · report
get_label_vector WilhelmT/ClassMix/evaluateSSL.py official repository ran · fixture could not drive it fingerprinted MIT (permissive) · 799a094d0124a46c · report
lr_poly WilhelmT/ClassMix/trainSSL.py official repository ran · honoured contract fingerprinted MIT (permissive) · b3b7c1c716f4ca66 · report
outS WilhelmT/ClassMix/model/deeplabv2.py official repository ran · honoured contract fingerprinted MIT (permissive) · 27504cbeb5811ea6 · report
Res_Deeplab WilhelmT/ClassMix/model/deeplabv2.py official repository unverified MIT (permissive) · 68fab2021abbbebf · report
colorJitter WilhelmT/ClassMix/utils/transformsgpu.py official repository unverified MIT (permissive) · bb18b872b207d4a2 · report
colorize_mask WilhelmT/ClassMix/utils/helpers.py official repository unverified MIT (permissive) · 980e8f8763638799 · report
convert_model WilhelmT/ClassMix/utils/sync_batchnorm/batchnorm.py official repository unverified MIT (permissive) · b0cd1f9681d630e2 · report
customsoftmax WilhelmT/ClassMix/utils/loss.py official repository unverified MIT (permissive) · d6015f0e8b0685cc · report
flip WilhelmT/ClassMix/utils/transformsgpu.py official repository unverified MIT (permissive) · 79963969c998c40d · report
gaussian_blur WilhelmT/ClassMix/utils/transformsgpu.py official repository unverified MIT (permissive) · b36157ea719029fe · report
generate_class_mask WilhelmT/ClassMix/utils/transformmasks.py official repository unverified MIT (permissive) · 78c73917d17c705c · report
generate_cow_mask WilhelmT/ClassMix/utils/transformmasks.py official repository unverified MIT (permissive) · db898bc1ff25e367 · report
generate_cutout_mask WilhelmT/ClassMix/utils/transformmasks.py official repository unverified MIT (permissive) · 50a4b555e559ce5e · report
get_iou WilhelmT/ClassMix/evaluateSSL.py official repository unverified MIT (permissive) · fb1d8f93c75b5433 · report
get_upsampling_weight WilhelmT/ClassMix/utils/helpers.py official repository unverified MIT (permissive) · 623804a7cb75739e · report
get_voc_palette WilhelmT/ClassMix/utils/palette.py official repository unverified MIT (permissive) · d46e561fba210e1a · report
sigmoid_ramp_up WilhelmT/ClassMix/trainSSL.py official repository unverified MIT (permissive) · d4002df13f6d42ed · report

Tasks

Data AugmentationSegmentationSemantic SegmentationSemi-Supervised Semantic Segmentation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Semi-Supervised Semantic Segmentation Cityscapes 100 samples labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 54.07% #12 of 13 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 12.5% labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 61.35% #30 of 33 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 2% labeled ClassMix (DeepLabv2 with ResNet101, MSCOCO pre-trained) Validation mIoU 52.14% #2 of 3 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 25% labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 63.63% #28 of 30 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 5% labeled ClassMix (DeepLabv2 with ResNet101, MSCOCO pre-trained) Validation mIoU 58.77% #2 of 3 Archive leaderboard report
Semi-Supervised Semantic Segmentation Cityscapes 50% labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 66.29% #22 of 23 Archive leaderboard report
Semi-Supervised Semantic Segmentation PASCAL VOC 2012 25% labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 72.45 #25 of 27 Archive leaderboard report
Semi-Supervised Semantic Segmentation Pascal VOC 2012 1% labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 54.18% #5 of 6 Archive leaderboard report
Semi-Supervised Semantic Segmentation Pascal VOC 2012 12.5% labeled ClassMix Validation mIoU 71.00% #30 of 38 Archive leaderboard report
Semi-Supervised Semantic Segmentation Pascal VOC 2012 2% labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 66.15% #7 of 12 Archive leaderboard report
Semi-Supervised Semantic Segmentation Pascal VOC 2012 5% labeled ClassMix (DeepLab v2 MSCOCO pretrained) Validation mIoU 67.77% #9 of 14 Archive leaderboard report

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