Papers › CDTrans: Cross-domain Transformer for Unsupervised Domain Adaptation

CDTrans: Cross-domain Transformer for Unsupervised Domain Adaptation

13 Sep 2021ICLR 2022 4arXiv:2109.06165archive 2025-07-28

Tongkun Xu, Weihua Chen, Pichao Wang, Fan Wang, Hao Li, Rong Jin

Unsupervised domain adaptation (UDA) aims to transfer knowledge learned from a labeled source domain to a different unlabeled target domain. Most existing UDA methods focus on learning domain-invariant feature representation, either from the domain level or category level, using convolution neural networks (CNNs)-based frameworks. One fundamental problem for the category level based UDA is the production of pseudo labels for samples in target domain, which are usually too noisy for accurate domain alignment, inevitably compromising the UDA performance. With the success of Transformer in various tasks, we find that the cross-attention in Transformer is robust to the noisy input pairs for better feature alignment, thus in this paper Transformer is adopted for the challenging UDA task. Specifically, to generate accurate input pairs, we design a two-way center-aware labeling algorithm to produce pseudo labels for target samples. Along with the pseudo labels, a weight-sharing triple-branch transformer framework is proposed to apply self-attention and cross-attention for source/target feature learning and source-target domain alignment, respectively. Such design explicitly enforces the framework to learn discriminative domain-specific and domain-invariant representations simultaneously. The proposed method is dubbed CDTrans (cross-domain transformer), and it provides one of the first attempts to solve UDA tasks with a pure transformer solution. Experiments show that our proposed method achieves the best performance on public UDA datasets, e.g. VisDA-2017 and DomainNet. Code and models are available at https://github.com/CDTrans/CDTrans.

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normalize cdtrans/cdtrans/loss/triplet_loss.py official repository ran · our draft was wrong fingerprinted MIT (permissive) · e3b2a83f52101f2d · report
cosine_dist cdtrans/cdtrans/loss/triplet_loss.py official repository unverified MIT (permissive) · 71b4e1d375d8fd78 · report
euclidean_dist cdtrans/cdtrans/loss/triplet_loss.py official repository unverified MIT (permissive) · 5315f75bf5367f0a · report
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read_image cdtrans/cdtrans/datasets/bases.py official repository unverified MIT (permissive) · 5f1101145f896208 · report
shear_x cdtrans/cdtrans/datasets/autoaugment.py official repository unverified MIT (permissive) · ec44d1cea891fdb3 · report
shear_y cdtrans/cdtrans/datasets/autoaugment.py official repository unverified MIT (permissive) · 368f32c4172985b4 · report
translate_x_rel cdtrans/cdtrans/datasets/autoaugment.py official repository unverified MIT (permissive) · aa897f695e05da40 · report

Tasks

Domain AdaptationUnsupervised Domain Adaptation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Domain Adaptation Office-31 CDTrans Average Accuracy 92.6 #5 of 40 Archive leaderboard report
Domain Adaptation Office-Home CDTrans (DeiT-B) Accuracy 80.5 #10 of 29 Archive leaderboard report
Domain Adaptation VisDA2017 CDTrans Accuracy 88.4 #11 of 28 Archive leaderboard report
Unsupervised Domain Adaptation Office-Home CDTrans Accuracy 80.5 #11 of 20 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

Absolute Position EncodingsAdamAttentionBPEConvolutionDense ConnectionsDropoutLabel SmoothingLayer NormalizationLinear LayerMulti-Head AttentionPosition-Wise Feed-Forward LayerResidual ConnectionSoftmaxTransformer

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