A Research Of Color Space Conversion Model Between Lab And CMYK

With the coming of Computer Intergraded Manufacturing and Multi-media, color is reproduced in different observation conditions or on different media. But In modern printing workflow, the colorimetric characterization of devices in every link, even the same model is different. This would lead to color information difficult to achieve accurate cross-media transmission and reproduction, and seriously affect the accuracy of color printing. In order to solve this problem, color management came into being. Through the use of Device-independent color space, the color spaces of each device will connected with each other, and achieve accurate color transmission and reproduction.The article will simply introduce the concept of color space and color management system. The keynotes are the establishment of mathematical conversion model from L*a*b*to CMYK and CMYK to L*a*b* ,and the test and verification of the precision of mathematical conversion model. It is the basis of establishment of our own color management. I have accomplished some following tasks:We first set up Lab-CMYK color space conversion model. We adopting the method of regression to work out coefficient of plane equation, and establishing three-color mathematical conversion model. Than we test the precision of mathematical conversion model. Finally, we acquire four-color mathematical conversion model which is based on the three-color mathematical conversion model. Besides, we inspect the precision.Than we select the RBF neural network set up CMYK-Lab color space conversion model. First of all, we study the structure of RBF neural networks and mathematical models, and initial create RBF neural network by using newrbe function. Than we determine the distribution coefficient by comparison test at the basis of training data. At last, the complete CMYK-Lab color space conversion model based on RBFN is finished and proved.Finally, we analyze those two models and summarize the whole experiments. The results show that the optimization model accuracy is improved. Therefore we should choose the appropriate algorithm in different color space transformation.