English

Pyramid-based Mamba Multi-class Unsupervised Anomaly Detection

Computer Vision and Pattern Recognition 2025-04-07 v1

Abstract

Recent advances in convolutional neural networks (CNNs) and transformer-based methods have improved anomaly detection and localization, but challenges persist in precisely localizing small anomalies. While CNNs face limitations in capturing long-range dependencies, transformer architectures often suffer from substantial computational overheads. We introduce a state space model (SSM)-based Pyramidal Scanning Strategy (PSS) for multi-class anomaly detection and localization--a novel approach designed to address the challenge of small anomaly localization. Our method captures fine-grained details at multiple scales by integrating the PSS with a pre-trained encoder for multi-scale feature extraction and a feature-level synthetic anomaly generator. An improvement of +1%+1\% AP for multi-class anomaly localization and a +1%1\% increase in AU-PRO on MVTec benchmark demonstrate our method's superiority in precise anomaly localization across diverse industrial scenarios. The code is available at https://github.com/iqbalmlpuniud/Pyramid Mamba.

Keywords

Cite

@article{arxiv.2504.03442,
  title  = {Pyramid-based Mamba Multi-class Unsupervised Anomaly Detection},
  author = {Nasar Iqbal and Niki Martinel},
  journal= {arXiv preprint arXiv:2504.03442},
  year   = {2025}
}
R2 v1 2026-06-28T22:46:46.612Z