4. Image Processing & Defect Detection Logic
4.1 Image Preprocessing
CCD signals transmitted synchronously by encoders are preprocessed via an acceleration card to enhance quality. Preprocessing steps include Fourier analysis for noise reduction, brightness and contrast adjustment, edge sharpening, and median filtering. This process suppresses interference, clarifies defect edges, and highlights defect features for accurate identification.
4.2 Gray Analysis & Defect Judgment
Theoretically, defect-free aluminum surfaces show continuous uniform gray values; in actual production, gray values fluctuate within a normal range. Once gray values exceed the threshold, combined with features such as brightness, contrast and occurrence frequency, the system preliminarily identifies potential defects.
4.3 Automatic Defect Recognition & Processing
The automatic recognition system matches collected signal features with preset standard ranges of common aluminum defects. After confirmation, defects are displayed in real time. The system also supports synchronous defect marking, full-roll surface quality grading, and complete quality data collection for traceability and production optimization.