Papers › Anchor-Free Person Search
Anchor-Free Person Search
Yichao Yan, Jinpeng Li, Jie Qin, Song Bai, Shengcai Liao, Li Liu, Fan Zhu, Ling Shao
Person search aims to simultaneously localize and identify a query person from realistic, uncropped images, which can be regarded as the unified task of pedestrian detection and person re-identification (re-id). Most existing works employ two-stage detectors like Faster-RCNN, yielding encouraging accuracy but with high computational overhead. In this work, we present the Feature-Aligned Person Search Network (AlignPS), the first anchor-free framework to efficiently tackle this challenging task. AlignPS explicitly addresses the major challenges, which we summarize as the misalignment issues in different levels (i.e., scale, region, and task), when accommodating an anchor-free detector for this task. More specifically, we propose an aligned feature aggregation module to generate more discriminative and robust feature embeddings by following a "re-id first" principle. Such a simple design directly improves the baseline anchor-free model on CUHK-SYSU by more than 20% in mAP. Moreover, AlignPS outperforms state-of-the-art two-stage methods, with a higher speed. Code is available at https://github.com/daodaofr/AlignPS
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Code
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Code Syntology ran Syntology
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Tasks
Results from the paper archive 2025-07-28
| Task | Dataset | Model | Metric | Value | Rank at snapshot | Leaderboard | Report |
|---|---|---|---|---|---|---|---|
| Person Search | CUHK-SYSU | AlignPS+ | MAP | 94 | #11 of 16 | Archive leaderboard | report |
| Person Search | CUHK-SYSU | AlignPS+ | Top-1 | 94.5 | #11 of 16 | Archive leaderboard | report |
| Person Search | CUHK-SYSU | AlignPS | MAP | 92.6 | #15 of 16 | Archive leaderboard | report |
| Person Search | CUHK-SYSU | AlignPS | Top-1 | 93.4 | #15 of 16 | Archive leaderboard | report |
| Person Search | PRW | AlignPS+ | Top-1 | 82.1 | #13 of 15 | Archive leaderboard | report |
| Person Search | PRW | AlignPS+ | mAP | 46.1 | #13 of 15 | Archive leaderboard | report |
| Person Search | PRW | AlignPS | Top-1 | 81.9 | #14 of 15 | Archive leaderboard | report |
| Person Search | PRW | AlignPS | mAP | 45.9 | #14 of 15 | 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
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