The Research And Implementation On Digital Color Proofing Technology

Printing is a process for transfering text and image, in which accurate color reproduction plays an important role. With the rapid development of digital pre-press system and the application of CTP (Computer to Plate), the traditional method of color printing that photograph the image three times using a filter is outdated, while the digital proofing becomes an indispensable technology. Now, the digital printing technique of four-color-process is wide use, while there is a problem that many domestic enterprises don't use spot color ink with pantone standard, and mix colors by hand for printing, so it is hard to generate a quality color reproduction. The research focuses on color control in digital printing technique of four-color-process and the contents are as follows.1. Establish the digital proofing environment with the existing equipment. Design the solution of digital proofing based on four-color-process. Expound the process of basic linearization of output device, and the establishment, correction, optimization of ICC-profile. Explore the method of quality control, and realize color quality control in four-color digital proofing.2. Design and construct the color library with EFI Color proof XF under the digital pre-press system. Adjust the color by comparing measured value with original value three times. Analyze the color gamut and color difference, and enhance the quality and the speed of digital proofing.3. Propose the model based on data fitting, which deduces the algorithm with Lab value fitting, and calculates the chromatic value of the colors with Matlab. Compare the measured value and adjusted value, and certify that the colors are completely satisfied the requirement of digital proofing.The research realizes the accurate color reproduction without use of the spot color ink. Propose the model based on data fitting to construct the color library. The library is dynamic and can be update at any time. It appropriates for production and enhances the quality and the speed of digital proofing.