SST-Net: Spatiotemporal Collaborative Attention for Sign Language Recognition

In complex environments, sign language recognition (SLR) is easily affected by background clutter, motion blur, and rapid movement. These factors can obscure subtle gesture patterns and weaken the discriminative spatiotemporal features required for recognition. To address these challenges, we propose SST-Net, a spatiotemporal collaborative attention enhancement framework for SLR. First, CGSA introduces input-dependent gates to dynamically fuse spatial and channel attention, rather than using fixed fusion weights. Second, the TFM and SFM both exploit inter-frame differences but use them differently: the TFM enhances motion-sensitive temporal features, whereas the SFM suppresses motion-dominated components to preserve spatial details; both are further refined through feature reweighting. Third, experiments on CSL-100, INCLUDE, and AUTSL show that SST-Net improves accuracy by 2–4 percentage points over strong baselines while using 35 M parameters and 115 GFLOPs, demonstrating a competitive balance between recognition performance and computational cost.