GaitGCI: Generative Counterfactual Intervention for Gait Recognition

Huanzhang Dou, Pengyi Zhang, Wei Su, Yunlong Yu, Yining Lin, Xi Li; Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR), 2023, pp. 5578-5588

Gait is one of the most promising biometrics that aims to identify pedestrians from their walking patterns. However, prevailing methods are susceptible to confounders, resulting in the networks hardly focusing on the regions that reflect effective walking patterns. To address this fundamental problem in gait recognition, we propose a Generative Counterfactual Intervention framework, dubbed GaitGCI, consisting of Counterfactual Intervention Learning (CIL) and Diversity-Constrained Dynamic Convolution (DCDC). CIL leverages causal inference to alleviate the impact of confounders by maximizing the likelihood difference between factual/counterfactual attention. DCDC adaptively generates sample-wise factual/counterfactual attention to perceive the sample properties. With matrix decomposition and diversity constraint, DCDC guarantees the model's efficiency and effectiveness. Extensive experiments indicate that proposed GaitGCI: 1) could effectively focus on the discriminative and interpretable regions that reflect gait patterns; 2) is model-agnostic and could be plugged into existing models to improve performance with nearly no extra cost; 3) efficiently achieves state-of-the-art performance on arbitrary scenarios (in-the-lab and in-the-wild).