Papers › Semi-Supervised Domain Generalizable Person Re-Identification

Semi-Supervised Domain Generalizable Person Re-Identification

11 Aug 2021arXiv:2108.05045archive 2025-07-28

Lingxiao He, Wu Liu, Jian Liang, Kecheng Zheng, Xingyu Liao, Peng Cheng, Tao Mei

Existing person re-identification (re-id) methods are stuck when deployed to a new unseen scenario despite the success in cross-camera person matching. Recent efforts have been substantially devoted to domain adaptive person re-id where extensive unlabeled data in the new scenario are utilized in a transductive learning manner. However, for each scenario, it is required to first collect enough data and then train such a domain adaptive re-id model, thus restricting their practical application. Instead, we aim to explore multiple labeled datasets to learn generalized domain-invariant representations for person re-id, which is expected universally effective for each new-coming re-id scenario. To pursue practicability in real-world systems, we collect all the person re-id datasets (20 datasets) in this field and select the three most frequently used datasets (i.e., Market1501, DukeMTMC, and MSMT17) as unseen target domains. In addition, we develop DataHunter that collects over 300K+ weak annotated images named YouTube-Human from YouTube street-view videos, which joins 17 remaining full labeled datasets to form multiple source domains. On such a large and challenging benchmark called FastHuman (~440K+ labeled images), we further propose a simple yet effective Semi-Supervised Knowledge Distillation (SSKD) framework. SSKD effectively exploits the weakly annotated data by assigning soft pseudo labels to YouTube-Human to improve models' generalization ability. Experiments on several protocols verify the effectiveness of the proposed SSKD framework on domain generalizable person re-id, which is even comparable to supervised learning on the target domains. Lastly, but most importantly, we hope the proposed benchmark FastHuman could bring the next development of domain generalizable person re-id algorithms.

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Code

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JDAI-CV/fast-reid officialmentioned in papermentioned on GitHubpytorch report
L1aoXingyu/reid_baseline mentioned on GitHubpytorchApache-2.0 report
xiaomingzhid/sskd mentioned on GitHubpytorch report

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3ran · our draft was wrong
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pairwise_circleloss JDAI-CV/fast-reid/fastreid/modeling/losses/circle_loss.py official repository ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 6507eb5ed85c4f59 · report
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compute_cosine_distance xiaomingzhid/sskd/fastreid/modeling/meta_arch/distiller.py community (archive-listed) ran · our draft was wrong fingerprinted Apache-2.0 (permissive) · 612e816a468670df · report
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drop_block_fast_2d L1aoXingyu/reid_baseline/fastreid/layers/drop.py community (archive-listed) ran Apache-2.0 (permissive) · 30d63ccefb97a166 · report
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get_norm L1aoXingyu/reid_baseline/fastreid/layers/batch_norm.py community (archive-listed) unverified Apache-2.0 (permissive) · 1211ac39b7d50139 · report

Tasks

Generalizable Person Re-identificationKnowledge DistillationPerson Re-IdentificationTransductive Learning

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Person Re-Identification Market-1501 SSKD(GH) Rank-1 97.36 #2 of 135 Archive leaderboard report
Person Re-Identification Market-1501 SSKD(GH) mAP 94.15 #2 of 135 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

Introduced by this paper: SSKD

1x1 ConvolutionAuxiliary ClassifierAverage PoolingBatch NormalizationBottleneck Residual BlockConvolutionGlobal Average PoolingKaiming InitializationKnowledge DistillationMax PoolingReLUResidual BlockResidual ConnectionSSKD

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