English
Related papers

Related papers: Unsupervised Two-Stage Anomaly Detection

200 papers

Anomaly detection consists in identifying, within a dataset, those samples that significantly differ from the majority of the data, representing the normal class. It has many practical applications, e.g. ranging from defective product…

Computer Vision and Pattern Recognition · Computer Science 2020-11-13 Pankaj Mishra , Claudio Piciarelli , Gian Luca Foresti

The core challenge in unsupervised anomaly detection is identifying abnormal patterns without prior knowledge of their characteristics. While existing methods have addressed aspects of this problem, they often struggle to learn a robust…

Machine Learning · Computer Science 2026-05-12 Prithul Sarker , Sushmita Sarker , Nicholas G. Murray , Alireza Tavakkoli

Image anomaly detection and localization perform not only image-level anomaly classification but also locate pixel-level anomaly regions. Recently, it has received much research attention due to its wide application in various fields. This…

Computer Vision and Pattern Recognition · Computer Science 2024-05-28 Chao Huang , Zhao Kang , Hong Wu

With the wide application of knowledge distillation between an ImageNet pre-trained teacher model and a learnable student model, unsupervised anomaly detection has witnessed a significant achievement in the past few years. The success of…

Computer Vision and Pattern Recognition · Computer Science 2026-04-07 Canhui Tang , Sanping Zhou , Yizhe Li , Yonghao Dong , Le Wang

Anomaly detection in medical imaging is a challenging task in contexts where abnormalities are not annotated. This problem can be addressed through unsupervised anomaly detection (UAD) methods, which identify features that do not match with…

Image and Video Processing · Electrical Eng. & Systems 2023-09-07 Geoffroy Oudoumanessah , Carole Lartizien , Michel Dojat , Florence Forbes

We aim at constructing a high performance model for defect detection that detects unknown anomalous patterns of an image without anomalous data. To this end, we propose a two-stage framework for building anomaly detectors using normal…

Computer Vision and Pattern Recognition · Computer Science 2021-04-12 Chun-Liang Li , Kihyuk Sohn , Jinsung Yoon , Tomas Pfister

Anomaly detection techniques enable effective anomaly detection and diagnosis in multi-variate time series data, which are of major significance for today's industrial applications. However, establishing an anomaly detection system that can…

Machine Learning · Computer Science 2024-05-02 Lingrui Yu

Despite the rapid advance of unsupervised anomaly detection, existing methods require to train separate models for different objects. In this work, we present UniAD that accomplishes anomaly detection for multiple classes with a unified…

Computer Vision and Pattern Recognition · Computer Science 2022-10-26 Zhiyuan You , Lei Cui , Yujun Shen , Kai Yang , Xin Lu , Yu Zheng , Xinyi Le

Unsupervised anomaly detection (UAD) has been widely implemented in industrial and medical applications, which reduces the cost of manual annotation and improves efficiency in disease diagnosis. Recently, deep auto-encoder with its variants…

Computer Vision and Pattern Recognition · Computer Science 2023-03-31 Mingqing Wang , Jiawei Li , Zhenyang Li , Chengxiao Luo , Bin Chen , Shu-Tao Xia , Zhi Wang

In contemporary society, surveillance anomaly detection, i.e., spotting anomalous events such as crimes or accidents in surveillance videos, is a critical task. As anomalies occur rarely, most training data consists of unlabeled videos…

Computer Vision and Pattern Recognition · Computer Science 2022-08-05 MyeongAh Cho , Taeoh Kim , Woo Jin Kim , Suhwan Cho , Sangyoun Lee

Anomaly detection in videos is a significant yet challenging problem. Previous approaches based on deep neural networks employ either reconstruction-based or prediction-based approaches. Nevertheless, existing reconstruction-based methods…

Computer Vision and Pattern Recognition · Computer Science 2023-01-31 Yizhou Wang , Can Qin , Yue Bai , Yi Xu , Xu Ma , Yun Fu

This paper proposed a novel anomaly detection (AD) approach of High-speed Train images based on convolutional neural networks and the Vision Transformer. Different from previous AD works, in which anomalies are identified with a single…

Computer Vision and Pattern Recognition · Computer Science 2022-03-30 Zhixue Wang , Yu Zhang , Lin Luo , Nan Wang

Anomaly detection (AD) in a surveillance scenario is an emerging and challenging field of research. For autonomous vehicles like drones or cars, it is immensely important to distinguish between normal and abnormal states in real-time.…

Computer Vision and Pattern Recognition · Computer Science 2020-07-15 Sayeed Shafayet Chowdhury , Kazi Mejbaul Islam , Rouhan Noor

Anomaly detection is a significant and hence well-studied problem. However, developing effective anomaly detection methods for complex and high-dimensional data remains a challenge. As Generative Adversarial Networks (GANs) are able to…

Machine Learning · Computer Science 2018-12-07 Houssam Zenati , Manon Romain , Chuan Sheng Foo , Bruno Lecouat , Vijay Ramaseshan Chandrasekhar

The main difficulty in high-dimensional anomaly detection tasks is the lack of anomalous data for training. And simply collecting anomalous data from the real world, common distributions, or the boundary of normal data manifold may face the…

Computer Vision and Pattern Recognition · Computer Science 2021-04-27 Songmin Dai , Jide Li , Lu Wang , Congcong Zhu , Yifan Wu , Xiaoqiang Li

Unsupervised anomaly detection (UAD) learns one-class classifiers exclusively with normal (i.e., healthy) images to detect any abnormal (i.e., unhealthy) samples that do not conform to the expected normal patterns. UAD has two main…

Computer Vision and Pattern Recognition · Computer Science 2021-07-01 Yu Tian , Guansong Pang , Fengbei Liu , Yuanhong chen , Seon Ho Shin , Johan W. Verjans , Rajvinder Singh , Gustavo Carneiro

Unsupervised anomaly detection (UAD) plays an important role in modern data analytics and it is crucial to provide simple yet effective and guaranteed UAD algorithms for real applications. In this paper, we present a novel UAD method for…

Machine Learning · Computer Science 2024-12-17 Wei Dai , Kai Hwang , Jicong Fan

In this study, a new Anomaly Detection (AD) approach for industrial and medical images is proposed. This method leverages the theoretical strengths of unsupervised learning and the data availability of both normal and abnormal classes.…

Computer Vision and Pattern Recognition · Computer Science 2024-01-24 Arnaud Bougaham , Valentin Delchevalerie , Mohammed El Adoui , Benoît Frénay

Accuracy anomaly detection in user-level social multimedia traffic is crucial for privacy security. Compared with existing models that passively detect specific anomaly classes with large labeled training samples, user-level social…

Cryptography and Security · Computer Science 2024-09-04 Tongtong Feng , Qi Qi , Jingyu Wang

Reconstruction-based approaches have achieved remarkable outcomes in anomaly detection. The exceptional image reconstruction capabilities of recently popular diffusion models have sparked research efforts to utilize them for enhanced…

Computer Vision and Pattern Recognition · Computer Science 2023-12-12 Haoyang He , Jiangning Zhang , Hongxu Chen , Xuhai Chen , Zhishan Li , Xu Chen , Yabiao Wang , Chengjie Wang , Lei Xie