Frequency-enhanced diffusion models: curriculum-guided semantic alignment for zero-shot skeleton action recognition
摘要
Human action recognition is pivotal in computer vision, with applications ranging from surveillance to human–robot interaction. Despite the effectiveness of supervised skeleton-based methods, their reliance on exhaustive annotation limits generalization to novel actions. Zero-shot skeleton action recognition emerges as a promising paradigm, yet it faces challenges due to the spectral bias of diffusion models, which oversmooth high-frequency dynamics. Here, we propose frequency-aware diffusion for skeleton-text matching, integrating a semantic-guided spectral residual module, a timestep-adaptive spectral loss, and curriculum-based semantic abstraction to address these challenges. Our approach effectively recovers fine-grained motion details, achieving state-of-the-art performance on NTU RGB+D, PKU-MMD, and Kinetics-skeleton datasets. Code has been made available at https://github.com/yuzhi535/FDSM. Project homepage: https://yuzhi535.github.io/FDSM.github.io/.