SALAD -- Semantics-Aware Logical Anomaly Detection
This work addresses a specific bottleneck in anomaly detection for industrial inspection, offering a significant improvement over prior methods.
The paper tackles the problem of logical anomaly detection, where existing methods struggle with irregular or missing object components, and proposes SALAD, a semantics-aware method that achieves a 96.1% image-level AUROC on the MVTec LOCO benchmark.
Recent surface anomaly detection methods excel at identifying structural anomalies, such as dents and scratches, but struggle with logical anomalies, such as irregular or missing object components. The best-performing logical anomaly detection approaches rely on aggregated pretrained features or handcrafted descriptors (most often derived from composition maps), which discard spatial and semantic information, leading to suboptimal performance. We propose SALAD, a semantics-aware discriminative logical anomaly detection method that incorporates a newly proposed composition branch to explicitly model the distribution of object composition maps, consequently learning important semantic relationships. Additionally, we introduce a novel procedure for extracting composition maps that requires no hand-made labels or category-specific information, in contrast to previous methods. By effectively modelling the composition map distribution, SALAD significantly improves upon state-of-the-art methods on the standard benchmark for logical anomaly detection, MVTec LOCO, achieving an impressive image-level AUROC of 96.1%. Code: https://github.com/MaticFuc/SALAD