Template3D-AD: Point Cloud Template Matching Method Based on Center Points for 3D Anomaly Detection

Abstract

Existing 3D anomaly detection methods mainly include reconstruction-based methods and memory-based methods. However, reconstruction-based methods rely on anomaly simulation strategies, while the memory bank of memory-based methods cannot cover the features of all points. Different from existing methods, this paper proposes Template3D-AD, a 3D anomaly detection method based on template matching. Template3D-AD matches the test sample with the template based on center points, and extracts the global features and local features of the center point respectively. Considering that the appearance of anomalies is related to the change of surface shape, this paper proposes a curvature-based local feature representation method, which increases the feature difference between abnormal surfaces and normal surfaces. Then, this paper designs a global-local detection strategy, which combines global feature differences and local feature differences for anomaly detection. Extensive experiments show that Template3D-AD outperforms the state-of-the-art methods, achieving 84.4% (1.5% ↑) I-AUROC on the Real3D-AD dataset and 86.5% (11.6% ↑) I-AUROC on the Anomaly-ShapeNet dataset. Code at https://github.com/CaedmonLY/Template3D-AD.