Papers › FDA: Fourier Domain Adaptation for Semantic Segmentation

FDA: Fourier Domain Adaptation for Semantic Segmentation

11 Apr 2020CVPR 2020 6arXiv:2004.05498archive 2025-07-28

Yanchao Yang, Stefano Soatto

We describe a simple method for unsupervised domain adaptation, whereby the discrepancy between the source and target distributions is reduced by swapping the low-frequency spectrum of one with the other. We illustrate the method in semantic segmentation, where densely annotated images are aplenty in one domain (synthetic data), but difficult to obtain in another (real images). Current state-of-the-art methods are complex, some requiring adversarial optimization to render the backbone of a neural network invariant to the discrete domain selection variable. Our method does not require any training to perform the domain alignment, just a simple Fourier Transform and its inverse. Despite its simplicity, it achieves state-of-the-art performance in the current benchmarks, when integrated into a relatively standard semantic segmentation model. Our results indicate that even simple procedures can discount nuisance variability in the data that more sophisticated methods struggle to learn away.

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Tasks

Domain AdaptationSegmentationSemantic SegmentationUnsupervised Domain Adaptation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Domain Adaptation Cityscapes to ACDC FDA (DeepLabv2) mIoU 45.7 #15 of 16 Archive leaderboard report
Domain Adaptation Panoptic SYNTHIA-to-Mapillary FDA mPQ 19.1 #4 of 5 Archive leaderboard report
Domain Adaptation SYNTHIA-to-Cityscapes FDA (VGG-16) mIoU 40.5 #30 of 33 Archive leaderboard report
Semantic Segmentation DADA-seg FDA mIoU 24.45 #15 of 28 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.

Methods

1x1 ConvolutionASPPAdamAverage PoolingBatch NormalizationBottleneck Residual BlockCRFConvolutionDeepLabv2Dense ConnectionsDilated ConvolutionDropoutFCNFeedforward NetworkGlobal Average PoolingKaiming InitializationMax PoolingReLUResidual BlockResidual ConnectionSGDSoftmaxSpatial Pyramid Pooling

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