The System For Color Printing Colorific Quality And Its DSP Implementation

With the tendency of the printing to low-volume, multicolor, high efficiency, it is inevitable that detection and control of the presswork color quality come forth. Traditional detection on the ground of density and chroma is based on color-mixing models, and the detection technology based upon this can only detect the accessional especial signal trip in the presswork. Thus the information can not be acquired from the presswork menu directly. So a new detection technique needs to be advanced to detect the presswork menu directly.Due to the drawback of methods and devices of inspecting and controlling printing images in current printing industry, the system for color printing colorific quality based on digital signal processing chip TMS320DM642 is designed. The system includes four parts: microscopic dot image acquisition, image separation processing, result display and function control. Color printing microscopic dot image is captured by image acquisition, which utilizes the LED illuminant, magnifier and vidicon. Image separation processing based on digital image processing and pattern recognition finishes dot separation by DM642. Result display shows the parameter such as dot image, dot area on LCD. Function control using AT89C51 single chip controls image acquisition, processing and display by uart.Based on analyzing the color trapping of color microscopic dots images, decision tree, clustering, fuzzy logic are been used in classifiers to deal with the color printing microscopic dot images . Then the infection of sheet to the printing quality is analyzed. Transplant and optimize the codes on DSP. In the end, the arithmetic is verified by different prospectus of different sheet and the error analysis is given. The next research direction is pointed out.The thesis will not only practical in online-detection and control of presswork color quality, but also contribute a lot in lucubrating color dots color theory and printing ink superimposition rule. The project is funded by the fund of youthful teacher with a master's degree in Xi'an University of Technology.