The precise prediction model of spectral reflectance for color halftone images

Abstract

In order to predict the spectral reflectance of color halftone images, we considered the scattering of light within paper and the ink penetration in the substrate and proposed the color spectral reflectance precise prediction model for halftone images. The paper based on the assumption that the colorant is non-scattering and the assumption that the paper is strong scattering substrate. By the multiple internal reflection between the paper substrate and the print-air interface of light, and the light along oblique path of the Williams-Clapper model, we propose this model for taking into account ink spreading, a phenomenon that occurs when printing an ink halftone in superposition with one or several solid inks. The ink-spreading model includes nominal-to-effective dot area coverage functions for each of the different ink overprint conditions by the least square curve fitting method and the network structure of multiple reflection. It turned out that the modeled and the measured colors agree very well, confirming the validity of the used model. The new model provides a theoretical foundation for color prediction analysis of halftone images and the development of prints quality detection system.