Efficient Color Printer Characterization Based on Extended Neugebauer Spectral Models

摘要

In order to print accurate colors on different substrates, color profiles must be created for each specific ink-media combination. We tackled the problem of creating such color profiles from only few color samples, in order to reduce the needed time of operation. Our strategy is to use a spectral reflectance prediction model in order to estimate a large sampling target (e.g. IT8.7/3) from only a small subset of color patches. In particular, we focused on the so-called Yule-Nielsen modified Spectral Neugebauer model, proposing new area coverage estimation, and a prediction of Neugebauer primaries, which can not be directly measured due to ink limiting. We reviewed the basis of such model, interpret it under the perspective of generalized averaging, and derived expressions to decouple optical and mechanical dot gain effects. The proposed area coverage estimations are based on assumptions of the printing process, and characterized through few extra color samples. We tested the models with thermal ink-jet printers on a variety of media, with dye-based and pigment-based inks. The IT8.7/3 target was predicted from 44 samples, with color average accuracy below 4 dE and maximum error below 8 dE, for dye-based inks, which performed better than pigment-based inks.