Publication Type
Conference Proceeding Article
Version
acceptedVersion
Publication Date
10-2022
Abstract
Unsupervised anomaly detection on image data is notoriously unstable. We believe this is because many classical anomaly detectors implicitly assume data is low dimensional. However, image data is always high dimensional. Images can be projected to a low dimensional embedding but such projections rely on global transformations that truncate minor variations. As anomalies are rare, the final embedding often lacks the key variations needed to distinguish anomalies from normal instances. This paper proposes a new embedding using a set of locally varying data projections, with each projection responsible for persevering the variations that distinguish a local cluster of instances from all other instances. The locally varying embedding ensures the variations that distinguish anomalies are preserved, while simultaneously allowing the probability that an instance belongs to a cluster, to be statistically inferred from the one-dimensional, local projection associated with the cluster. Statistical agglomeration of an instance’s cluster membership probabilities, creates a global measure of its affinity to the dataset and causes anomalies to emerge, as instances whose affinity scores are surprisingly low.
Keywords
anomaly detection, unsupervised, high dimensions, Bayesian
Discipline
Databases and Information Systems | Graphics and Human Computer Interfaces
Research Areas
Data Science and Engineering
Publication
Computer Vision ECCV 2022: 17th European Conference, Tel Aviv, Israel, October 23-27: Proceedings
Volume
13690
First Page
354
Last Page
371
ISBN
9783031200564
Identifier
10.1007/978-3-031-20056-4_21
Publisher
Springer
City or Country
Cham
Citation
LIN, Wen-yan; LIU, Zhonghang; and LIU, Siying.
Locally varying distance transform for unsupervised visual anomaly detection. (2022). Computer Vision ECCV 2022: 17th European Conference, Tel Aviv, Israel, October 23-27: Proceedings. 13690, 354-371.
Available at: https://ink.library.smu.edu.sg/sis_research/7310
Copyright Owner and License
Authors
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Additional URL
https://doi.org/10.1007/978-3-031-20056-4_21
Included in
Databases and Information Systems Commons, Graphics and Human Computer Interfaces Commons