On-line Detection System Of Paper Defects Based On High-speed Camera

As modern paper production has become more and more high-speed andautomatic, the artificial detection of paper defects could not meet the accuracyand effectiveness. This paper mainly researched on the on-line detection of paperinformation with high-speed camera, realized counting and identifying thelocation of paper defects, such as folds、gaps、holes、stains, and analysed thereason that aroused these problem to avoid generating the paper defects.The principle and function of the online paper defects detection system wasdescribed, by studying the performance requirements of system, the properhardware such as light source、camera、capture card and encoder were selected;The best lighting solutions、 encoder denoising circuit and mechanicalconstruction of the system were designed.The judgement of paper defects and extraction of the defects informationhave been realized by the combination of gray segmentation algorithm、edgedetecting algorithm and the theory of fractal dimension. By means of countingand analyzing the gray values of paper defects, the difference between paperdefects and background of image was found out. The hole and gap could bejudged whether they were exist or not based on dynamic threshold segmentationalgorithm, and the pixel values of paper defects were replaced with the meanvalue of the whole image. By calculating the number of pixels detected by theRoberts operator, the folds could be judged.The location,area and minimum external rectangle were deduced from thebinary image by boundary tracking algorithm, and based on the box dimensionalvalue, the paper defects could be distinguished, then all these information ofpaper defects were saved.The interfaces design of system login, parameter setting, lasted inquireswere achieved by visual c++, and debugged the whole system from the combinations of camera、video capture card、encoder and so on. The systemprocessing effect was validated. The result showed that this detection methodpossessed good quality and efficiency and it is meaningful to improve theworking conditions.