Research On Quality Inspection System Of Color Print Based On Full Screen

Printing quality testing and control has been one of the focus of attention in the industry.With the rapid development of modern science and technology, people's demand for print quality is also increasing. Therefore, the printing quality inspection and analysis methods and technology research has always been the industry's attention, but also in the better. In order to overcome the limitation of the traditional detection method, the direct detection based on the full print quality has become the current research hotspot. To this end, this paper based on previous studies, carried out based on full-screen color print quality inspection technology research and system development. The main work of this subject and the results achieved are as follows:(1) Using Adobe Photoshop CS5 design platform, designed and produced experimental color target. Through the actual printing, access to print color and ISO300 standard color images. After the image is scanned, the RGB values of the scanning patches are read by self programming and the corresponding L*a*b* values are obtained by manual measurement. Thus providing the basic data for the establishment and precision analysis of the RGB-L*a*b* color space conversion model.(2) Based on the analysis and comparison of different conversion methods and their precision, the RGB-L*a*b* color space transformation model based on this experimental data is established. By using the third-order 20-term polynomial regression algorithm as the subject Color space conversion model.(3) In-depth study on the theory of defect detection of printed matter, and the basic ideas and methods of color defect detection in printed matter are put forward. That is, based on the CIELAB color difference formula, the color defects and sub-regional color defects of the whole picture are calculated respectively, and the corresponding color quality evaluation standard of the printed matter is set, and the quality of the color reproduction is judged objectively.(4) According to the characteristics of scanning image, the image denoising and image registration operation are completed on the basis of studying various mature algorithms. By means of comparative analysis, the standard template image is produced by threshold method.On this basis, a full-screen detection experiment was carried out, and the color defect analysis and sub-region color defect analysis of the whole image of the printed image were completed.(5) Using Visual Studio 2013 as a platform, we use Qt good interface design, OpenCV open source library and MATLAB to develop a set of print color defect detection prototype system based on full screen evaluation, and realize the basic function of color defect detection.