Energy-Based Pseudo-Label Refining for Source-free Domain Adaptation
Xinru Meng, Han Sun, Jiamei Liu, Ningzhong Liu, Huiyu Zhou
TL;DR
This work tackles the challenge of source-free domain adaptation by reducing pseudo-label noise through energy-based refinement. It introduces EBPR, a framework that generates pseudo-labels via transport-cost-based clustering, applies adaptive energy thresholds to filter labels, and uses enhanced consistency training for hard samples, all without access to source data. Empirical results on Office-31, Office-Home, and VisDA-C demonstrate state-of-the-art performance and improved handling of class-imbalance and noisy labels. The approach offers a practical, robust pathway for SFDA, though it incurs higher computational cost on very large datasets.
Abstract
Source-free domain adaptation (SFDA), which involves adapting models without access to source data, is both demanding and challenging. Existing SFDA techniques typically rely on pseudo-labels generated from confidence levels, leading to negative transfer due to significant noise. To tackle this problem, Energy-Based Pseudo-Label Refining (EBPR) is proposed for SFDA. Pseudo-labels are created for all sample clusters according to their energy scores. Global and class energy thresholds are computed to selectively filter pseudo-labels. Furthermore, a contrastive learning strategy is introduced to filter difficult samples, aligning them with their augmented versions to learn more discriminative features. Our method is validated on the Office-31, Office-Home, and VisDA-C datasets, consistently finding that our model outperformed state-of-the-art methods.
