Choosing Wisely and Learning Deeply: Selective Cross-Modality Distillation via CLIP for Domain Generalization
Jixuan Leng, Yijiang Li, Haohan Wang
TL;DR
This work tackles domain generalization by introducing Selective Cross-Modality Distillation (SCMD), which distills from CLIP into a single-modal student using a hard-to-learn sample selector and a cross-modality projection that aligns student features with CLIP's text embeddings. The method combines supervised learning, a logits-KL distillation term, and a CLIP-guided cross-modal loss, with a theoretical bound showing that focusing on high-loss samples tightens robustness to distribution shift. Empirically, SCMD achieves state-of-the-art results on the DomainBed DG benchmarks, and ablations confirm that both the hard-sample selection and the cross-modality module contribute meaningfully to performance. The findings suggest that selective, cross-modal knowledge transfer is a practical and effective strategy for improving domain generalization in vision tasks.
Abstract
Domain Generalization (DG), a crucial research area, seeks to train models across multiple domains and test them on unseen ones. In this paper, we introduce a novel approach, namely, Selective Cross-Modality Distillation for Domain Generalization (SCMD). SCMD leverages the capabilities of large vision-language models, specifically CLIP, to train a more efficient model, ensuring it acquires robust generalization capabilities across unseen domains. Our primary contribution is a unique selection framework strategically designed to identify hard-to-learn samples for distillation. In parallel, we introduce a novel cross-modality module that seamlessly combines the projected features of the student model with the text embeddings from CLIP, ensuring the alignment of similarity distributions. We assess SCMD's performance on various benchmarks, where it empowers a ResNet50 to deliver state-of-the-art performance, surpassing existing domain generalization methods. Furthermore, we provide a theoretical analysis of our selection strategy, offering deeper insight into its effectiveness and potential in the field of DG.
