고정밀 머신 비전을 위한 정확한 PCB 윤곽선과 코너 검출 = Accurate PCB out line extraction and corner detection for high precision machine vision

다국어 초록 (Multilingual Abstract)

Recently, Advances in technology have increased the importance of visual inspection in semiconductor inspection areas. In PCB visual inspection, the accuracy of the line estimation used in the preceding calibration, alignment, etc., is critical to the accuracy of the entire instrument. We propose line estimation that is differently weighted for the line candidates using a histogram of gradient information, when the position of the initial approximate corner points were known. Using the obtained line equation of the outline, we can detect the accurate corner points in the picture. The corner points by the proposed method are compared with the existing method. The proposed method accurately detect corner in the situation when the existing methods have problem such as overlap, misdetection, etc. In high-resolution frame of 3.5mega-pixels, the proposed method operates at a speed of 89.01ms which can be processed in the real-time.

참고문헌 (Reference)

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