UniAD: Integrating Geometric and Semantic Cues for Unified Anomaly Detection

Current anomaly detection paradigms face inherent limitations in simultaneously addressing structural anomalies (e.g., geometric distortions) and logical anomalies (e.g., semantic inconsistencies), due to conflicting feature representation requirements between these two anomaly categories. We propose UniAD, a novel dual-branch teacher-student framework that achieves unified anomaly detection through synergistic integration of complementary expertise from heterogeneous vision models without requirements of extra manual annotations. In particular, our framework integrates two frozen expert models as teachers: (1) a structural teacher specializing in geometric-sensitive patterns, and (2) a logical teacher focusing on semantic-aware representations via component relationship modeling. To resolve feature conflicts while preserving complementary information, the student network is equipped with one shared backbone and two independent branches. One branch employs multi-scale feature alignment with the structural teacher while another branch establishing semantic correspondence with the logical teacher through component-aware attention mechanisms. Furthermore, we introduce the text-guided semantic enhancement module as a kind of logical guidance to facilitate the anomaly indicator. Extensive experiments on the challenging MVTec LOCO benchmark validate that the scalability of our model to localize both geometric distortions and semantic inconsistencies. The proposed method outperforms existing single-purpose detectors, yielding 93.7% AUROC for logical anomalies and 93.2% AUROC for structural anomalies.