Vocabulary-Guided Gait Recognition
Organizations: School of Artificial Intelligence, Beijing Normal University
Abstract
What is a gait? Appearance-based gait networks consider a gait as the human shape and motion information from images. Model-based gait networks treat a gait as the human inherent structure from points. However, the considerations remain vague for humans to comprehend truly. In this work, we introduce a novel paradigm Vocabulary-Guided Gait Recognition, dubbed Gait-World, which attempts to explore gait concepts through human vocabularies with Vision-Language Models (VLMs). Although VLMs have achieved the remarkable progress in various vision tasks, the cognitive capability regarding gait modalities remains limited. The success element in Gait-World is the proper vocabulary prompt where this paradigm carefully selects gait cycle actions as Vocabulary Base, bridging the gait and vocabulary feature spaces and further promoting human understanding for the gait. How to extract gait features? Although previous gait networks have made significant progress, learning solely from gait modalities on limited gait databases makes it difficult to learn universal gait features for practicality. Therefore, we propose the first Gait-World model, dubbed α-Gait, which guides the gait network learning with vocabulary knowledge from VLMs. However, due to the heterogeneity of the modalities, directly integrating vocabulary and gait features is highly challenging as they reside in different embedding spaces. To address the issues, α-Gait designs Vocabulary Relation Mapper and Gait Fine grained Detector to map and establish vocabulary relations in the gait space for detecting corresponding gait features. Extensive experiments on CASIA-B, CCPG, SUSTech1K, Gait3D and GREW reveal the potential value and research directions of vocabulary information from VLMs in the gait field.
Figures & tables
| Paradigm | Method | Venue | Gait Evaluation Protocol | ReID Evaluation Protocol | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CL | UP | DN | BG | Mean | CL | UP | DN | BG | Mean | |||
| Model | GaitGraph2 Teepe et al. (2021) | CVPRW22 | 5.0 | 5.3 | 5.8 | 6.2 | 5.1 | 5.0 | 5.7 | 7.3 | 8.8 | 6.7 |
| Gait-TR Zhang et al. (2023) | ES23 | 15.7 | 18.3 | 18.5 | 17.5 | 17.5 | 24.3 | 28.7 | 31.1 | 28.1 | 28.1 | |
| MSGG Peng et al. (2024b) | MTA23 | 29.0 | 34.5 | 37.1 | 33.3 | 33.5 | 43.1 | 52.9 | 57.4 | 49.9 | 50.8 | |
| SkeletonGait Fan et al. (2024) | AAAI24 | 40.4 | 48.5 | 53.0 | 61.7 | 50.9 | 52.4 | 65.4 | 72.8 | 80.9 | 67.9 | |
| Appearance | GaitSet Chao et al. (2019) | AAAI19 | 60.2 | 65.2 | 65.1 | 68.5 | 64.8 | 77.5 | 85.0 | 82.9 | 87.5 | 83.2 |
| Paradigm | Method | Venue | Probe Sequence | Overall | ||||||||
| NM | BG | CL | CRY | UMB | UNI | OCC | NT | Rank-1 | Rank-5 | |||
| Model | GaitGraph2 Teepe et al. (2021) | CVPRW22 | 22.2 | 18.2 | 6.8 | 18.6 | 13.4 | 19.2 | 27.3 | 16.4 | 18.6 | 40.2 |
| Gait-TR Zhang et al. (2023) | ES23 | 33.3 | 31.5 | 21.0 | 30.4 | 22.7 | 34.6 | 44.9 | 23.5 | 30.8 | 56.0 | |
| MSGG Peng et al. (2024b) | MTA23 | 67.1 | 66.2 | 35.9 | 63.3 | 61.6 | 58.1 | 66.6 | 17.9 | 33.8 | - | |
| SkeletonGait Fan et al. (2024) | AAAI24 | 67.9 | 63.5 | 36.5 | 61.6 | 58.1 | 67.2 | 79.1 | 50.1 | 63.0 | 83.5 | |
| Appearance | GaitSet Chao et al. (2019) | AAAI19 | 69.1 | 68.2 | 37.4 | 65.0 | 63.1 | 61.0 | 67.2 | 23.0 | 65.0 | 84.8 |
| Paradigm | Method | Venue | NM | BG | CL | Mean |
| Model | GaitGraph2 Teepe et al. (2022) | CVPRW22 | 80.3 | 71.4 | 63.8 | 71.8 |
| GaitTR Zhang et al. (2023) | ES23 | 94.7 | 89.3 | 86.7 | 90.2 | |
| GPGait Fu et al. (2023) | ICCV23 | 93.6 | 80.2 | 69.3 | 81.0 | |
| Appearance | GaitSet Chao et al. (2019) | AAAI19 | 95.0 | 87.2 | 70.4 | 84.2 |
| GaitPart Fan et al. (2020) | CVPR20 | 96.2 | 91.5 | 78.7 | 88.8 | |
| GLN Hou et al. (2020) | ECCV20 | 96.9 | 94.0 | 77.5 | 89.5 |
| Paradigm | Method | Venue | Gait3D | GREW | ||||
|---|---|---|---|---|---|---|---|---|
| Rank-1 | Rank-5 | mAP | Rank-1 | Rank-5 | Rank-10 | |||
| Model | GaitGraph2 Teepe et al. (2022) | CVPRW22 | 11.2 | - | - | 64.8 | - | - |
| GaitTR Zhang et al. (2023) | ES23 | 7.2 | - | - | 48.6 | - | - | |
| GPGait Fu et al. (2023) | ICCV23 | 22.4 | - | - | 57.0 | - | - | |
| Appearance | GaitSet Chao et al. (2019) | AAAI19 | 36.7 | 58.3 | 30.0 | 46.3 | 63.6 | 70.3 |
| GaitPart Fan et al. (2020) | CVPR20 | 28.2 | 47.6 | 47.6 | 44.0 | 60.7 | 67.3 | |
| Method | Gait3D | CCPG | |||||
| Rank-1 | mAP | CL | UP | DN | BG | Mean | |
| -Gait | 76.2 | 67.8 | 82.8 | 89.0 | 84.6 | 92.7 | 87.3 |
| Gait Encoder | 73.6 | 65.1 | 80.1 | 86.4 | 83.9 | 91.4 | 85.5 |
| The analysis on Text Encoder | |||||||
| Initial Random | 71.8 | 63.3 | 77.7 | 84.2 | 77.6 | 86.2 | 81.4 |
| Learnable Query | 74.1 | 66.8 | 82.3 | 89.0 | 83.9 | 92.5 | 86.9 |
| Paradigm | Variant | Vocabulary Base | Rank-1 | mAP |
|---|---|---|---|---|
| Appearance | Gait Encoder | — | 73.6 | 65.1 |
| Gait Encoder w/ -Gait | [8 phases] | 76.2 | 67.8 | |
| Model | SkeletonGait | — | 37.9 | 29.6 |
| SkeletonGait w/ -Gait | [8 phases] | 40.3 | 31.3 | |
| Multimodel | SkeletonGait++ | — | 76.0 | 69.2 |
| SkeletonGait++ w/ -Gait | [8 phases] | 78.1 | 71.5 |
Appendix figures & tables1 asset
Supplementary material from the paper’s appendix.
Appendix
| Environment | Dataset | Train | Test | Condition | Stage | Channels | Strides | ||
| Id. | Seq. | Id. | Seq. | [ , , , ] | [ , , , ] | ||||
| Constrained | CASIA-B Yu et al. (2006) | 74 | 8,140 | 50 | 5,500 | CV, BG, CL | [1, 1, 1, -] | [64, 128, 256, -] | [1, 2, 1, -] |
| CCPG Li et al. (2023) | 100 | 8,187 | 100 | 8,095 | CV, BG, CL | [1, 1, 1, 1] | [64, 128, 256, 512] | [1, 2, 2, 1] | |
| In-the-wild | SUSTech1K Shen et al. (2023) | 200 | 5988 | 850 | 19,228 | Real-world | [1, 1, 1, 1] | [64, 128, 256, 512] | [1, 2, 2, 1] |
| Gait3D Zheng et al. (2022b) | 3,000 | 18,940 | 1,000 | 6,369 | Real-world | [1, 4, 4, 1] | [64, 128, 256, 512] | [1, 2, 2, 1] | |
| GREW Zhu et al. (2021) | 20,000 | 102,887 | 6,000 | 24,000 | Real-world | [2, 4, 4, 2] | [64, 128, 256, 512] | [1, 2, 2, 1] | |