Moon: A Modality Conversion-Based Efficient Multivariate Time Series Anomaly Detection

作者：Yuanyuan Yao, Yuhan Shi, Lu Chen, Ziquan Fang, Yunjun Gao, Leong Hou U, Yushuai Li, Tianyi Li · 发表于：IEEE Transactions on Knowledge and Data Engineering · 年份：2025 · DOI：10.1109/tkde.2025.3622154 · 被引用次数：1 · 研究领域：Anomaly Detection Techniques and Applications、Time Series Analysis and Forecasting、Software System Performance and Reliability

Multivariate time series (MTS) anomaly detection identifies abnormal patterns where each timestamp contains multiple variables. Existing MTS anomaly detection methods fall into three categories: reconstruction-based, prediction-based, and classifier-based methods. However, these methods face three key challenges: (1) Unsupervised learning methods, such as reconstruction-based and prediction-based methods, rely on error thresholds, which can lead to inaccuracies; (2) Semi-supervised methods mainly model normal dataand often underuse anomaly labels, limiting detection of subtle anomalies; (3) Supervised learning methods, such as classifier-based approaches, often fail to capture local relationships, incur high computational costs, and are constrained by the scarcity of labeled data. To address these limitations, we proposeMoon, a supervised modality conversion-based multivariate time series anomaly detection framework.Moonenhances the efficiency and accuracy of anomaly detection while providing detailed anomaly analysis reports. First,Moonintroduces a novel multivariate Markov Transition Field (MV-MTF) technique to convert numeric time series data into image representations, capturing relationships across variables and timestamps. Since numeric data retains unique patterns that cannot be fully captured by image conversion alone,Moonemploys a Multimodal-CNN to integrate numeric and image data through a feature fusion model with parameter sharing, enhancing training efficiency. F...