Organizations: School of Artificial Intelligence, Beijing Normal University · Department of Computer Science and Engineering, The University of Texas at Arlington
"What I cannot create, I do not understand."Human wisdom reveals that creation is one of the highest forms of learning. For example, Diffusion Models have demonstrated remarkable semantic structure and memory in image generation, understanding, and restoration, which intuitively benefits representation learning. However, current gait networks rarely embrace this perspective, relying primarily on learning by contrasting gait samples under varying complex conditions, leading to semantic inconsistency and uniformity issues. To address these issues, we propose Origins with generative capabilities whose underlying philosophy is that different entities are generated from a unified template, inherently regularizing gait representations within a consistent and diverse semantic space to capture accurate gait differences. Admittedly, learning this unified template is exceedingly challenging, as it requires the comprehensiveness of the template to encompass gait representations with various conditions. Inspired by Diffusion Models, Origins diffuses the unified template into timestep templates for gait generative learning, and meanwhile transfers the unified template for gait representation learning. Especially, gait generative and representation learning serve as a unified framework for end-to-end joint training. Extensive experiments on CASIA-B, CCPG,SUSTech1K, Gait3D, GREW and CCGR-MINI demonstrate that Origins performs unified generative and representation learning, achieving superior performance.
Figures & tables
Figure 1: Origins performs unified generative and representation learning. The unified template T diffuses to the timestep templates, which generates gait representations. Meanwhile, the unified template T transfers to capture accurate gait differences.
Figure 2: The unified template is the consistent and diverse space. The different semantic dimensions in this unified template linearly construct each gait representation.
Figure 3: More timestep templates enable better convergence and more precise recognition performance.
Figure 4: The heatmaps show that the unified template generates the missing human body parts for information supplementation and matching ( e.g . , the regions in the red circle of the left and right figures), and rectifies temporal information ( e.g . , the region in the red circle of the middle figure).
Figure 5: The gait network with Origins. HP represents Horizontal Partition, and Visual Stage consists of basic convolution blocks. After the gait silhouette sequence passes through Visual Encoder and HP, the part representations are fed into the respective Origins and Recognition Head for generative and representation learning.
Figure 6: The overview of Origins, best viewed in colors and shapes. The N , C4 and Z denote the number, dimension and multi-heads of timestep templates. The unified template T diffuses timestep templates by time serialization for generation and transfers information to gait representations for recognition.
Environment
Dataset
Train
Test
Condition
Stage
Channels
Strides
Id.
Seq.
Id.
Seq.
[ D1 , D2 , D3 , D4 ]
[ C1 , C2 , C3 , C4 ]
Constrained
CASIA-B [ 66 ]
74
8,140
50
5,500
CV, BG, CL
[1, 1, 1. -]
[64, 128, 256, -]
[1, 2, 1, -]
CCPG [ 29 ]
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 [ 45 ]
200
5988
850
19,228
Real-world
[1, 1, 1, 1]
[64, 128, 256, 512]
[1, 2, 2, 1]
CCGR-MINI [ 73 ]
571
27507
399
20377
Real-world
[1, 4, 4, 1]
[64, 128, 256, 512]
[1, 2, 2, 1]
Gait3D [ 70 ]
3,000
18,940
1,000
6,369
Real-world
[1, 4, 4, 1]
[64, 128, 256, 512]
[1, 2, 2, 1]
Table 1: DataBase and Architectures. Id. and Seq. denote the number of identities and sequences. CV, BG and CL refer to cross-view and carrying bags and cross-clothing conditions. D and C denote the number of conv blocks and the channels in each visual stage.
Paradigm
Method
Venue
Gait Evaluation Protocol
ReID Evaluation Protocol
CL
UP
DN
BG
Mean
CL
UP
DN
BG
Mean
Model
GaitGraph2 [ 48 ]
CVPRW22
5.0
5.3
5.8
6.2
5.1
5.0
5.7
7.3
8.8
6.7
Gait-TR [ 68 ]
ES23
15.7
18.3
18.5
17.5
17.5
24.3
28.7
31.1
28.1
28.1
MSGG [ 40 ]
MTA23
29.0
34.5
37.1
33.3
33.5
43.1
52.9
57.4
49.9
50.8
SkeletonGait [ 11 ]
AAAI24
40.4
48.5
53.0
61.7
50.9
52.4
65.4
72.8
80.9
67.9
Appearance
GaitSet [ 3 ]
AAAI19
60.2
65.2
65.1
68.5
64.8
77.5
85.0
82.9
87.5
83.2
Table 2: The performance comparisons on CCPG under various conditions, including full-body cloth changes (CL), upper-body cloth changes (UP), lower-body cloth changes (DN), and backpacks changes (BG), reported with Rank-1 accuracy (%).
Paradigm
Method
Venue
Probe Sequence (Rank-1)
Overall
Normal
Bag
Clothing
Carrying
Umbrella
Uniform
Occlusion
Night
Rank-1
Rank-5
Model
GaitGraph2 [ 48 ]
CVPRW22
22.2
18.2
6.8
18.6
13.4
19.2
27.3
16.4
18.6
40.2
Gait-TR [ 68 ]
ES23
33.3
31.5
21.0
30.4
22.7
34.6
44.9
23.5
30.8
56.0
MSGG [ 40 ]
MTA23
67.11
66.16
35.92
63.31
61.58
58.07
66.59
17.88
33.8
-
SkeletonGait [ 11 ]
AAAI24
67.9
63.5
36.5
61.6
58.1
67.2
79.1
50.1
63.0
83.5
Appearance
GaitSet [ 3 ]
AAAI19
69.1
68.2
37.4
65.0
63.1
61.0
67.2
23.0
65.0
84.8
Table 3: The performance comparisons on SUSTech1K are reported with Rank-1 and Rank-5 accuracy (%).
Method
Venue
NM
BG
CL
Mean
GaitSet [ 3 ]
AAAI19
95.0
87.2
70.4
84.2
GaitPart [ 12 ]
CVPR20
96.2
91.5
78.7
88.8
GLN [ 21 ]
ECCV20
96.9
94.0
77.5
89.5
GaitGL [ 32 ]
ICCV21
97.4
94.5
83.6
91.8
QAGait [ 58 ]
AAAI24
97.9
94.6
78.2
90.2
GaitBase [ 10 ]
CVPR23
97.6
94.0
77.4
89.8
Table 4: The performance comparisons on CASIA-B are reported with Rank-1 accuracy (%).
Method
Venue
Rank-1
Rank-5
mAP
GaitSet [ 3 ]
AAAI19
36.7
58.3
30.0
GaitPart [ 12 ]
CVPR20
28.2
47.6
47.6
GaitGL [ 32 ]
ICCV21
29.7
48.5
22.3
SMPLGait [ 70 ]
CVPR22
46.3
64.5
37.2
MTSGait [ 69 ]
MM22
48.7
67.1
37.6
QAGait [ 58 ]
AAAI24
67.0
81.5
56.5
Table 5: The performance comparisons on Gait3D are reported with Rank-1, Rank-5 accuracy and mAP (%).
Method
Venue
Rank-1
Rank-5
Rank-10
GaitSet [ 3 ]
AAAI19
46.3
63.6
70.3
GaitPart [ 12 ]
CVPR20
44.0
60.7
67.3
GaitGL [ 32 ]
ICCV21
47.3
63.6
-
MTSGait [ 69 ]
MM22
55.3
71.3
76.9
QAGait [ 58 ]
AAAI24
59.1
74.0
79.2
GaitBase [ 10 ]
CVPR23
60.1
-
-
Table 6: The performance comparisons on GREW are reported with Rank-1, Rank-5 and Rank-10 accuracy (%).
Method
Venue
Rank-1
mAP
mINP
GaitSet [ 3 ]
AAAI19
13.77
15.39
5.75
GaitPart [ 12 ]
CVPR20
8.02
10.12
3.52
GaitGL [ 32 ]
ICCV21
17.51
18.12
6.85
GaitBase [ 10 ]
CVPR23
26.99
24.89
9.72
DeepGaitV2 [ 9 ]
TPAMI25
39.37
36.01
16.77
Origins-M ( ours )
-
41.45
38.31
24.71
Table 7: The performance comparisons on CCGR-MINI are reported with Rank-1 accuracy, mAP and mINP (%).
Figure 7: The “elements” axe is Z that is the number of multi-heads in the template. The visualization shows that different subjects exhibit differences in the template.
Method
Gait3D
Rank-1
Rank-5
mAP
Origins-M
75.8
86.8
67.0
The analysis on the core modules
-w/o Origins
73.6
86.9
65.1
- w/o Transferring Unified Template
74.4
87.9
67.1
- w/o Diffusing Timestep Templates
75.3
86.4
66.3
Table 8: The core module analysis on Gait3D.
Method
Gait3D
CASIA-B
Rank-1
Rank-5
mAP
NM
BG
CL
Mean
Origins-M
75.8
86.8
67.0
99.3
97.4
90.3
95.7
Baseline
73.6
86.9
65.1
98.2
95.8
84.4
92.8
The analysis on the number of timestep templates
N=8
75.3
87.0
66.5
99.1
97.3
90.4
95.6
N=16
75.8
86.8
67.0
99.3
97.4
90.3
95.7
Table 9: The timestep template analysis on Gait3D and CASIA-B.
Cajal Neuroscience Center, Spanish National Research Council (CSIC), Madrid, Spain · Bioengineering Systems and Technologies Research Group, Rey Juan Carlos University (URJC), Madrid, Spain