Research On Color-Difference Evaluation For Printed Sample Based On CIECAM02 Color Appearance Model

Along with the development of color science technology, the evaluation of color reproduction effect about color presswork become more and more quantify, the research on uniformity of color space and color-difference prediction performance of color-difference formulae is an important project in the field of color science currently. In order to better solve the problem on evaluation of color reproduction effect, a kind of mathematical model for simulate mechanism of human vision, that is color appearance model has been proposed. Using the color appearance model CIECAM02 proposed lately to evaluate color difference will be the future trend, the research on color-difference prodiction proformance of color-difference formulae based on CIECAM02 color appearance model has great significance.The evaluation of color-difference has been widely used in printing industry, but the research on color-difference evaluation was not aim at printed sample specifility. The experiment in this paper using three kinds of coated paper with difference gloss as substrate, study color-difference prediction proformance of both color-difference formulae CIECAM02-LCD, CIECAM02-UCS, CIECAM02-SCD based on CIECAM02 color appearance model and classical color-difference formula CIELAB, CIE94, CMC, CIEDE2000 based on CIEL*a*b* uniform color space about printed sample in just perceptible small color-difference and medium color-difference range, discussing the impact on color-difference evaluation for different gloss paper. Then each original color-difference formula will be optimized, and the color-difference prediction performance of optimized formulae will be compared and analyzed.Research on color-difference evaluation of small color-difference and medium color-difference printed sample shows that, the color-difference formulae CIECAM02-SCD, CIECAM02-UCS, CIECAM02-LCD based on CIECAM02 color appearance model have good consistency respectively with visual evaluation of small and medium color-difference; analysis of experiment data about different gloss paper shows that, color-difference evaluation will be influenced by the size of gloss, mainly for the weight factor of brightness. Therefore, this factor should be considered in color-difference evaluation. The original data and reference for the development and amelioration of uniform color space and color-difference formulae can be supplied by the experimental results of this paper, meanwhile it can provide some reference for color-difference evaluation of printed sample.