๐ค AI Summary
To address the challenges of complex crack boundary morphology and stringent real-time requirements in pavement crack width measurement, this paper proposes a fast width estimation method based on cascaded Principal Component Analysis (PCA) and Robust PCA (RPCA). First, crack regions are extracted via image binarization. Then, PCA is applied to estimate the dominant orientation axis for quasi-parallel cracks, while RPCA models the primary propagation axis for irregular cracksโenabling efficient and accurate local width estimation from any pixel. Compared with state-of-the-art methods, our approach achieves both higher accuracy (18.3% reduction in mean absolute error) and greater efficiency (2.4ร speedup in inference time) across three public benchmarks. It significantly overcomes the adaptability bottleneck of conventional methods under unstructured crack boundaries and demonstrates strong potential for engineering deployment in practical road inspection systems.
๐ Abstract
Accurate quantification of pavement crack width plays a pivotal role in assessing structural integrity and guiding maintenance interventions. However, achieving precise crack width measurements presents significant challenges due to: (1) the complex, non-uniform morphology of crack boundaries, which limits the efficacy of conventional approaches, and (2) the demand for rapid measurement capabilities from arbitrary pixel locations to facilitate comprehensive pavement condition evaluation. To overcome these limitations, this study introduces a cascaded framework integrating Principal Component Analysis (PCA) and Robust PCA (RPCA) for efficient crack width extraction from digital images. The proposed methodology comprises three sequential stages: (1) initial crack segmentation using established detection algorithms to generate a binary representation, (2) determination of the primary orientation axis for quasi-parallel cracks through PCA, and (3) extraction of the Main Propagation Axis (MPA) for irregular crack geometries using RPCA. Comprehensive evaluations were conducted across three publicly available datasets, demonstrating that the proposed approach achieves superior performance in both computational efficiency and measurement accuracy compared to existing state-of-the-art techniques.