基于光谱的喷墨打印设备全墨色特性化高效建模方法研究

Color printer characterization is the key to the color reproduction accuracy of ink jet printing. According to the fact that the existing characterization methods always suffer from the problem of metamerism, high dot visibility and low modeling efficiency, in this research a novel approach focusing on the efficient modeling for spectral printer characterization with total ink channels is proposed, with the aim of improving the overall performance of printer characterization from the aspects of rationality, comprehensiveness and efficiency. Basing on the mechanism of human vision perception, the complementary ink separation curves as well as the simulating and quantification method for dot visibility are deduced. Afterward, the formerly proposed spectral printer characterization workflow for principal ink channels , which consists of several substeps such as printer division, ink limitation, spectral prediction, spectral separation and metric optimization, was extended to the total-ink-channels modeling level. Besides, in order to conquer the sampling redundancy for the analytical spectral printer models, certain constrained optimization algorithm is proposed. Basing on the above mentioned approaches, a novel printer characterization workflow is achieved, which could maintain excellent spectral reproduction accuracy, low dot visibility and high modeling efficiency simultaneously, and thus theoretically and practically provides support for ink-jet based color reproduction.

喷墨设备色彩特性化建模是保证喷墨色彩复制精度的关键。针对目前设备特性化建模过程所存在的同色异谱、墨点可见性高以及建模效率低三大问题，提出从光谱反射率层面构建喷墨打印设备全墨色特性化模型的高效建模方法，以期系统的揭示全墨色作用下半色调光谱色彩再现的机理与规律，保证特性化建模的合理性、完整性及高效性。围绕特性化过程中存在的空间拆分降维、墨量限制、打印光谱预测、光谱分色以及建模度量优化等关键问题，依据人眼视觉感知机理，通过辅色墨水分色曲线及打印墨点可见性仿真量化方法的构建，将申请人前期研究构建的打印机主墨色光谱特性化建模方法向全墨色层面进行扩展。在此基础上，利用约束最优化算法实现面向光谱维度分析模型的特性化样本寻优，克服传统方法所具有的采样冗余问题，进一步实现模型精度、墨点可见性以及建模效率三者的兼顾，为喷墨打印技术在色彩复制方面的发展提供理论与方法支撑。

喷墨设备色彩特性化建模是保证喷墨色彩复制精度的关键。针对目前设备特性化建模过程所存在的同色异谱、墨点可见性高以及建模效率低三大问题，本课题提出了从光谱反射率层面构建喷墨设备全墨色分色模型的高效建模方法，一定程度上揭示了全墨色作用下半色调光谱色彩再现的机理与规律，保证分色建模的合理性、完整性及高效性。..项目以课题组前期研究构建的基于光谱的喷墨设备色彩特性化流程为基础，通过墨点可见性仿真与量化，实现了建模过程中有关墨点可见问题的有效控制；通过辅色墨水分色曲线的构建，将全墨色建模问题转化为主色墨色建模问题，进而实现全墨色建模研究与现有主色建模研究成果的关联；通过分色算法优化、不同介质批量建模方法构建、面向复制对象的设备拆分建模、基于墨量限制样本的特性化样本优化以及不同照明条件下色彩一致性校正等方法，大幅提升了现有特性化建模效率，实现了高效建模优化。..本项目累计发表学术论文11篇，其中SCI检索论文8篇，完成既定任务。在专利申请方面，从分色建模样本优化、分色算法优化、拆分建模优化等角度累计申请发明专利5项，另获授权发明专利4项。目前，相关专利技术已应用于多家企业，如与利兹大学肖开达博士（CIE颜色技术皮肤色分组主席）进行合作，对典型皮肤色光谱反射率数据进行了色卡制备，用于法国欧莱雅公司研究项目。