RcAE: Recursive Reconstruction Framework for Unsupervised Industrial Anomaly Detection

TL;DR

The paper introduces RcAE, a recursive autoencoder framework with a detection module and detail preservation, significantly improving unsupervised industrial anomaly detection by progressively suppressing anomalies and recovering fine details.

Contribution

It proposes a novel recursive autoencoder architecture with a cross recursion detection module and detail preservation network, enhancing anomaly suppression and detection accuracy.

Findings

Outperforms existing non-diffusion methods in anomaly detection.

Achieves comparable performance to diffusion models with fewer parameters.

Offers faster inference suitable for real-world applications.

Abstract

Unsupervised industrial anomaly detection requires accurately identifying defects without labeled data. Traditional autoencoder-based methods often struggle with incomplete anomaly suppression and loss of fine details, as their single-pass decoding fails to effectively handle anomalies with varying severity and scale. We propose a recursive architecture for autoencoder (RcAE), which performs reconstruction iteratively to progressively suppress anomalies while refining normal structures. Unlike traditional single-pass models, this recursive design naturally produces a sequence of reconstructions, progressively exposing suppressed abnormal patterns. To leverage this reconstruction dynamics, we introduce a Cross Recursion Detection (CRD) module that tracks inconsistencies across recursion steps, enhancing detection of both subtle and large-scale anomalies. Additionally, we incorporate a Detail Preservation Network (DPN) to recover high-frequency textures typically lost during reconstruction. Extensive experiments demonstrate that our method significantly outperforms existing non-diffusion methods, and achieves performance on par with recent diffusion models with only 10% of their parameters and offering substantially faster inference. These results highlight the practicality and efficiency of our approach for real-world applications.