Dynamic facial expression recognition in the wild remains challenging due to data scarcity and long-tail distributions, which hinder models from effectively learning the temporal dynamics of scarce emotions. To address these limitations, we propose ARGen, an Affect-Reinforced Generative Augmentation Framework that enables data-adaptive dynamic expression generation for robust emotion perception. ARGen operates in two stages: Affective Semantic Injection (ASI) and Adaptive Reinforcement Diffusion (ARD). The ASI stage establishes affective knowledge alignment through facial Action Units and employs a retrieval-augmented prompt generation strategy to synthesize consistent and fine-grained affective descriptions via large-scale visual-language models, thereby injecting interpretable emotional priors into the generation process. The ARD stage integrates text-conditioned image-to-video diffusion with reinforcement learning, introducing inter-frame conditional guidance and a multi-objective reward function to jointly optimize expression naturalness, facial integrity, and generative efficiency. Extensive experiments on both generation and recognition tasks verify that ARGen substantially enhances synthesis fidelity and improves recognition performance, establishing an interpretable and generalizable generative augmentation paradigm for vision-based affective computing.
Figures & tables
Figure 1: (a) demonstrates the long-tail distribution in terms of category sample counts and recognition accuracy in existing datasets. (b) demonstrates the incremental performance of our ARGen method in addressing the challenge of recognizing scarce facial expressions.
Figure 2: Overall framework of ARGen . The framework incorporates emotional priors derived from facial action units through vision-language models, followed by efficient video generation using diffusion models optimized via reinforcement learning.
Method & Architecture
Status
DFEW
FERV39k
WAR
UAR
AR-SU
AR-DI
AR-FE
WAR
UAR
AR-SU
AR-DI
AR-FE
Training from Scratch
Res18_LSTM
Original
63.66
51.85
51.02
0.00
35.91
43.04
32.13
19.44
5.78
9.51
ARGen
65.22 ( 1.56 ↑ )
53.25 ( 1.40 ↑ )
52.80 ( 1.78 ↑ )
6.90 ( 6.90 ↑ )
38.58 ( 2.67 ↑ )
44.46 ( 1.42 ↑ )
34.42 ( 2.29 ↑ )
21.67 ( 2.23 ↑ )
11.85 ( 6.07 ↑ )
11.23 ( 1.72 ↑ )
Res18_Transformer
Original
66.59
55.60
52.82
5.52
36.92
45.96
35.29
22.10
11.78
11.83
ARGen
67.60 ( 1.01 ↑ )
56.70 ( 1.10 ↑ )
55.54 ( 2.72 ↑ )
11.72 ( 6.20 ↑ )
39.48 ( 2.56 ↑ )
46.52 ( 0.56 ↑ )
36.90 ( 1.61 ↑ )
23.82 ( 1.72 ↑ )
14.06 ( 2.28 ↑ )
12.99 ( 1.16 ↑ )
Table 1: ARGen’s performance comparison (%) of different recognition baselines on DFEW and FERV39k.
Method
FVD ↓
sFVD ↓
tFVD ↓
DynamiCrafter ( Xing et al. 2024 )
170.16
345.16 ± 137.32
208.35 ± 45.79
TI2V-Zero ( Ni et al. 2024 )
81.72
170.20 ± 57.90
109.41 ± 47.26
ARGen(ours)
56.75
133.62 ± 50.94
81.21 ± 27.07
Table 2: ARGen’s quantitative comparison of different methods for generation on CK+.
Figure 3: Visualization of generation performance for scarce categories in DFEW and FERV39k. The green box indicates the input neutral reference frame and brown markers represent adaptive policy selection results for the input in ARD. We generated 16 video frames throughout the experiments and the four frames shown correspond to frames 1, 6, 11, and 16. The three sections, from top to bottom, represent the emotions of surprise, disgust, and fear.
Ablation
WAR
UAR
AR-SU
AR-DI
AR-FE
Original(w/o TA)
64.50
52.83
50.34
0.00
34.96
Original(w/ TA)
66.59
55.60
52.82
5.52
36.92
ARGen(w/o ASI)
67.31
56.39
55.10
6.90
35.36
Δ
+1.08%
+1.42%
+4.13%
+25.00%
-4.23%
ARGen(w/o ARD)
67.06
54.98
54.79
6.21
37.73
Δ
+0.71%
-1.12%
+3.73%
+12.5%
+2.19%
Table 3: Ablation study on two-stage performance comparison (%) of ARGen on DFEW using Res18_Transformer. “TA” refers to the traditional image data augmentation methods we use in our setup.
Rewards
FVD ↓
sFVD ↓
tFVD ↓
RQ
RF,RE
✗
✗
85.87
187.55 ± 75.36
112.98 ± 48.22
✓
✗
65.39
164.19 ± 62.72
102.28 ± 46.15
✗
✓
78.96
203.93 ± 78.24
119.44 ± 60.51
✓
✓
56.75
133.62 ± 50.94
81.21 ± 27.07
Table 4: ARGen’s quantitative comparison of different rewards for generation on CK+.
Figure 4: Additional visualizations. The green box indicates the reference frame, while the subsequent three frames represent frames 5, 10, and 15. From top to bottom, represent the emotions of surprise, disgust, and fear.
Ablation
FVD ↓
sFVD ↓
tFVD ↓
ARGen w/o ARD
Fixed prompts (baseline)
85.87
187.55 ± 75.36
112.98 ± 48.22
VLM-only
78.40
172.10 ± 63.50
108.30 ± 44.10
VLM+RAG
69.20
157.35 ± 60.85
92.50 ± 35.47
ARGen w/o ASI
Reinforce-only
66.80
150.18 ± 55.40
90.04 ± 30.25
Table 5: More detailed ablation experiments on CK+ dataset for ARGen submodules.
Department of Computer Science, University of the Punjab, Lahore, Pakistan · Department of Computer Science, Information Technology University, Lahore, Pakistan