DADKC: Distribution-Aware Adaptive Differentiated Knowledge Consolidation for Cloth-Hybrid Lifelong Person Re-identification
Authors: Yan Zhang, Minghao Long, Meiqi Wan, Yan Yang, Xin Yuan, Wei Wang, Xiao Wang
Organizations: School of Computer Science and Technology, Wuhan University of Science and Technology, Wuhan 430065, China · State Key Laboratory of Robotics and Intelligent Systems, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China · China University of Chinese Academy of Sciences, Beijing 100049, China · Hubei Province Key Laboratory of Intelligent Information Processing and Real-Time Industrial System, Wuhan University of Science and Technology, Wuhan 430065, China
Lifelong Person Re-identification (LReID) aims to match the same person using sequentially collected data. In practical long-term deployments, however, the model must handle both domain shifts across cameras and scenes, and irregular clothing changes of the same identity. This gives rise to the Cloth-Hybrid Lifelong Person Re-identification (CH-LReID) task, which demands balancing cloth-relevant and cloth-irrelevant knowledge in streaming data. While existing LReID methods have explored replay-based or distillation-based anti-forgetting strategies, they typically fail to sufficiently model stage-aware domain distributions and cross-stage feature continuity under exemplar-free training. To address this problem, we propose a Distribution-Aware Adaptive Differentiated Knowledge Consolidation (DADKC) framework. The core idea is to enhance the existing Differentiated Knowledge Consolidation (DKC) paradigm with adaptive distribution modeling. To this end, three lightweight modules are designed: (1) an Anchor Pool Adapter (APA) to retrieve learnable anchor cues for refining identity features; (2) a Phase Path Mixer (PPM) to perform stage-aware expert routing for integrating domain-specific distribution paths; and (3) a Stage Bridge Alignment (SBA) module to regularize the continuity of base, anchor, and path representations between adjacent stages. Extensive experiments on the CH-LReID and LReID benchmarks show that DADKC gains 4.1%/4.5% mAP/R1 on Order-1 and 3.6%/3.4% mAP/R1 on Order-2 over the DKC baseline, and lowers weighted forgetting from 2.4%/1.7% to 1.8%/1.4%, while storing neither historical images nor per-image features. The code is available at https://github.com/fire667/DADKC.
Figures & tables
Figure 1: Paradigm comparison of LReID methods: rehearsal-based methods replay exemplars, rehearsal-free methods avoid raw samples but may lose cross-stage continuity, and DADKC performs distribution-aware differentiated consolidation.
Figure 2: Overall framework of DADKC. A DKC-style backbone extracts base and uncertainty representations; APA retrieves anchor cues, PPM routes through stage-aware experts, and SBA aligns current and previous-stage base, anchor, and path features. The final model uses accumulated experts and an unknown-domain embedding at test time.
Method
Cloth-Consistent
Cloth-Changing
Average
Market
LTCC
PRCC
MSMT17
CUHK03
Avg.
LTCC
PRCC
Avg.
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
Joint
64.1
82.5
42.6
62.1
94.6
98.7
18.4
40.8
44.4
46.4
52.8
66.1
10.1
23.0
32.7
33.8
21.4
28.4
43.8
55.3
SFT
28.5
52.0
28.5
49.3
92.5
97.3
7.0
19.6
44.0
45.6
40.1
52.8
6.9
15.3
21.8
21.2
14.4
18.3
32.7
42.9
AKA (CVPR 2021) [ 10 ]
48.0
69.5
25.4
45.1
88.1
93.3
4.2
12.0
31.2
31.2
39.4
50.2
6.5
12.8
26.5
26.7
16.5
19.8
32.8
41.5
PatchKD (ACM MM 2022) [ 15 ]
68.0
85.5
30.8
54.7
93.5
96.5
5.7
15.6
33.2
32.9
46.2
57.0
7.2
17.9
26.1
26.0
16.7
22.0
37.8
47.0
Table 1: Order-1 performance. DKC-reported values are from DKC [ 1 ] ; DKC-controlled and DADKC are common-code five-seed means.
Method
Cloth-Consistent
Cloth-Changing
Average
MSMT17
PRCC
Market
CUHK03
LTCC
Avg.
PRCC
LTCC
Avg.
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
mAP
R1
Joint
18.4
40.8
94.6
98.7
64.1
82.5
44.4
46.4
42.6
62.1
52.8
66.1
32.7
33.8
10.1
23.0
21.4
28.4
43.8
55.3
SFT
2.4
9.1
84.5
95.9
16.9
37.2
8.2
8.8
37.9
57.6
30.0
41.7
21.9
24.3
9.1
20.9
15.5
22.6
25.8
36.3
AKA (CVPR 2021) [ 10 ]
15.0
32.4
93.0
97.0
26.6
51.0
13.4
11.6
43.4
64.0
38.3
51.2
28.2
27.7
8.4
15.8
18.3
21.8
32.6
42.8
PatchKD (ACM MM 2022) [ 15 ]
22.6
47.9
95.0
98.5
38.2
64.2
21.8
23.1
45.8
70.0
44.7
60.7
28.1
27.6
9.3
21.7
18.7
24.7
37.3
50.4
Table 2: Order-2 performance. DKC-reported values are from DKC [ 1 ] ; DKC-controlled and DADKC are common-code five-seed means.
Method
Order-3
Order-4
Average
mAP
R1
mAP
R1
mAP
R1
CRL (WACV 2021) [ 33 ]
40.5
50.8
37.6
49.2
39.1
50.0
AKA (CVPR 2021) [ 10 ]
40.8
50.8
38.6
49.4
39.7
50.1
PatchKD (ACM MM 2022) [ 15 ]
43.7
53.7
43.2
54.1
43.5
53.9
LSTKC (AAAI 2024) [ 24 ]
50.0
63.1
49.6
62.1
49.8
62.6
DKP (CVPR 2024) [ 23 ]
51.8
64.1
51.3
63.2
51.6
63.7
Table 3: Traditional cloth-consistent LReID results. Baselines are from DKC [ 1 ] ; DKC-controlled and DADKC are five-seed means.
Method
Same (5 evals.)
Cross (2 evals.)
Weighted all
AF(mAP/R1) ↓
AF(mAP/R1) ↓
AF(mAP/R1) ↓
AKA (CVPR 2021) [ 10 ]
12.9/13.8
5.0/6.8
10.6/11.8
LSTKC (AAAI 2024) [ 24 ]
15.9/13.0
7.5/9.3
13.5/11.9
USP (TCSVT 2024) [ 27 ]
13.6/11.8
5.6/7.3
11.3/10.5
PatchKD (ACM MM 2022) [ 15 ]
6.3/6.3
4.5/5.4
5.8/6.0
DKP (CVPR 2024) [ 23 ]
7.8/6.2
3.0/4.8
6.4/5.8
Table 4: Order-1 AF results. Same and Cross average five and two evaluations; Weighted all uses 5:2 weighting. Lower is better.
Variant
Purpose
Avg. mAP
Avg. R1
DKC-reported
published reference
44.2
55.8
DKC + matched MLP
capacity control
44.5
56.0
DKC + generic feature KD
alignment control
44.6
56.3
DKC + generic MoE
routing control
44.8
56.4
DKC + APA
anchor only
44.7
56.3
DKC + PPM
path only
44.9
56.5
Table 5: Order-1 component and capacity analysis. DKC-reported is the published reference; other rows are common-pipeline five-seed variants.
Parameter
Values
Avg. mAP
Avg. R1
M
64/128†/256
45.3 / 45.7 / 45.4
57.1 / 57.6 / 57.2
K
4/8†/12
45.1 / 45.7 / 45.5
56.9 / 57.6 / 57.3
E
3/5†/7
45.4 / 45.7 / 45.3
57.2 / 57.6 / 57.1
λapa=λppm
.05/.10†/.20
45.3 / 45.7 / 45.4
57.2 / 57.6 / 57.3
λsba
.005/.01†/.02
45.4 / 45.7 / 45.5
57.3 / 57.6 / 57.4
Table 6: Order-1 sensitivity. † marks the default used by every main table.
Method
Params
GFLOPs
Train GB
ms/image
Growth/stage
DKC
28.7M
4.11
7.2
4.8
0
Matched MLP
31.1M
4.45
7.8
5.2
0
DADKC
31.2M
4.48
9.9
5.5
0.48M
Table 7: Resource profile after five stages. Training memory includes the frozen SBA teacher; latency is single-image inference after warm-up.
Figure 3: t-SNE visualization of learned representations on training Order-1 . Different colors represent different identities, and △ , ◯ denote two randomly sampled identities with different clothes.
Figure 4: Performance tendency at different training stages on Order-1 .
Wangxuan Institute of Computer Technology, Peking University, Beijing, China · University of Chinese Academy of Sciences, Beijing, China · Intelligent Science & Technology Academy of CASIC, Beijing 100041, China