cs.CVMar 3, 2026

Improving Anomaly Detection with Foundation-Model Synthesis and Wavelet-Domain Attention

Authors: Wensheng Wu, Zheming Lu, Ziqian Lu, Zewei He, Xuecheng Sun, Zhao Wang, Jungong Han, Yunlong Yu

Organizations: School of Aeronautics and Astronautics, Zhejiang University, Hangzhou, 310027, China · School of Computer Science and Technology(), , Hangzhou, 310018, China · Ningbo Innovation Center, Zhejiang University, Ningbo, China · Department of Automation, Tsinghua University, Beijing, 100084, China · 

Abstract

Industrial anomaly detection faces significant challenges due to the scarcity of anomalous samples and the complexity of real-world anomalies. In this paper, we propose a foundation model-based anomaly synthesis pipeline (FMAS) that generates highly realistic anomalous samples without fine-tuning or class-specific training. Motivated by the distinct frequency-domain characteristics of anomalies, we introduce aWavelet Domain Attention Module (WDAM), which exploits adaptive sub-band processing to enhance anomaly feature extraction. The combination of FMAS and WDAM significantly improves anomaly detection sensitivity while maintaining computational efficiency. Comprehensive experiments on MVTec AD and VisA datasets demonstrate that WDAM, as a plug-and-play module, achieves substantial performance gains against existing baselines.

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