Scalable optoelectronic ATM network for workstations

基于灰份替代新方法的彩色打印系统光谱特征化

“…Grey component replacement (GCR) and under colour removal (UCR) technologies are extensively used for black generation [2,3] . These could be applied further in the spectral characterisation model of colour printer for recovery of spectral reflectance of colour target and avoidance of metamerism [4,5] .…”

“…where D(λ) is the spectral density of the target colour at wavelength λ, R 0 (λ) and R(λ) are the spectral reflectance of the substrate (white paper) and the target colour at wavelength λ, respectively. Generally, the conventional GCR method is based on the assumption that the primary colour densities are additive [3,4] . However, the additivity does not exactly hold in practice and the so-called additivity failure frequently occurs [7] .…”

“…These occurrences could be caused by plenty of reasons, such as the complex interaction between ink and paper, light scattering, halftone structure, etc. In the study of Zeng [4] , colorimetric density was used to implement the GCR method for direct colorimetric mapping. To solve the problem caused by the additivity failure, the author proposed a refinement algorithm by simply adjusting cyan, magenta, and yellow (CMY) values to compensate for the density additivity error and to keep the K value unchanged according to a feedback process.…”

“…Likewise, the CIELAB colour difference mean of 1.2318 and max value of 3.9307, together with the CIEDE2000 colour difference mean of 0.9620 and max value of 3.3559 showed high colorimetric prediction accuracy compared with those of other published studies. The GCR method of Kang [4] , which aimed at spectral fit, achieved the prediction accuracy mean of 3.11 and maximum 5 CIELAB units. In the study of Zeng [3] , a higher accuracy mean of 0.8 and maximum 2.4 CIELAB units were accomplished by focusing on direct colorimetric mapping.…”