Few-shot person re-identification based on Feature Set Augmentation and Metric Fusion

Person re-identification identifies pedestrians by analyzing image information from surveillance videos. However, it faces challenges like occlusion, changing lighting, and costly annotation. Thus, it is often performed in a few-shot environment with limited images. In response to the problem of insufficient available pedestrian images in person re-identification, a few-shot person re-identification method based on feature set augmentation and metric fusion is proposed. In this work, firstly, a feature augmentation method is introduced into the feature embedding module. This method introduces multi-head self-attention in different feature extraction layers and spatial attention in feature fusion of different feature extraction layers, which can extract more diverse and discriminative pedestrian features. Secondly, a dual metric method combining Euclidean and cosine distance is proposed in the metric module to comprehensively measure the absolute spatial distance and directional difference of pedestrian features. In this way, the reliability of pedestrian similarity measurement is improved. Then, pedestrian feature similarity scores are obtained separately using the dual metric and relation metric methods. Finally, the combined metric score is obtained by weighted fusion, and the combined metric score is used to construct the joint loss to realize the overall optimization and training of the network. Experimental results on three small datasets, Market-mini, Duke-mini, and MSMT17-mini, show that the proposed method significantly improves recognition performance compared to other few-shot learning algorithms. Specifically, in scenarios 5-way 1-shot and 5-way 5-shot, the average recognition accuracies are 92.54% and 96.99%, 87.93% and 96.08%, and 71.68% and 84.51%, respectively.