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VQGNet: An Unsupervised Defect Detection Approach for Complex Textured Steel Surfaces
Ronghao Yu1, Yun Liu1, Rui Yang1
1Center for Adaptive System Engineering, ShanghaiTech University, Shanghai 201210, China.
Sensors (Basel, Switzerland)
|October 16, 2024
Summary
VQGNet, an unsupervised algorithm, accurately identifies and segments defects on complex steel surfaces. This novel approach overcomes data limitations and improves industrial inspection accuracy.
Area of Science:
- Materials Science
- Computer Vision
- Artificial Intelligence
Background:
- Defect detection on steel surfaces with complex textures is challenging due to limited defect samples and complex annotations.
- Accurate defect segmentation is difficult, especially with intricate surface patterns.
Purpose of the Study:
- To propose VQGNet, an unsupervised algorithm for simultaneous defect recognition and segmentation on steel surfaces.
- To address the challenges of limited data and complex texture in industrial defect detection.
Main Methods:
- Developed VQGNet, an unsupervised algorithm integrating aggregated attention and a classification-aided module.
- Employed multi-scale feature fusion and neighbor feature aggregation for confident anomaly map generation.
- Introduced an anomaly generation method for grayscale images to aid model learning.
Main Results:
- VQGNet achieved state-of-the-art performance on an industrial steel dataset.
- Achieved I-AUROC of 99.6%, I-F1 of 98.8%, P-AUROC of 97.0%, and P-F1 of 80.3%.
- Demonstrated robust generalization with ViT-Query on the Kolektor Surface-Defect Dataset.
Conclusions:
- VQGNet effectively segments and classifies defects by focusing on anomalous information over complex textures.
- The proposed methods enhance anomaly detection confidence and model learning capabilities.
- VQGNet offers a powerful solution for unsupervised defect detection and segmentation in industrial applications.
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