WR-Former: Vision Transformer with Weight Reallocation Module for Robust Facial Expression Recognition

Facial expression recognition(FER) is an exceedingly challenging task in the field of computer vision, primarily due to variant head poses, occlusions and illumination conditions. Previous methods focus on extracting more facial features to improve the performance on the FER benchmarks. However, most of them ignore the weights of the key regions. To address the above problem, this paper proposes a vision Transformer with weight reallocation module termed as WR-Former. The weight reallocation module utilizes a hybrid multi-head self-attention and can dynamically iterate during the training process. It guides the model to reallocate tokens based on the importance of different facial regions. Besides, a simple yet effective data augmentation method is proposed to expand training samples and improve the robustness. Experimental results and visualizations demonstrate that our WR-Former outperforms the previous state-of-the-art methods and has the ability to better extract the features conveyed by the key facial regions.