基于阈上小色差的色差公式权重函数研究

利用心理物理实验的恒常刺激法,测得了在CIELAB颜色空间中a*b*平面上16个颜色中心的阈上小色差(约3ΔE*ab单位)色度椭圆.基于本实验和RIT-Dupont各16个非中性色颜色中心的彩度差和色调差数据分别拟合得到相应的彩度权重函数SC_ZJU07和色调权重函数SH_ZJU07.应用获得的视觉实验数据对六个基于CIELAB的典型色差公式的彩度和色调权重函数以及SC_ZJU07和SH_ZJU07的色差预测性能进行评价,结果表明所提出的SC_ZJU07和SH_ZJU07的预测性能均为最佳.对于彩度差数据,六个色差公式彩度权重函数的预测性能表现不佳;而对于色调差数据,CIEDE2000色调权重函数的预测性能明显优于其他公式.

Investigations for Weighting Functions of Color-Difference Formulae Based on Small Suprathreshold Color Differences

Small suprathreshold color-difference (about 3 ΔE*ab units) chromaticity ellipses at 16 color centers in the a*b* plane of CIELAB space were measured using the psychophysical method of constant stimuli. The corresponding chroma weighting function SC_ZJU07 and hue weighting function SH_ZJU07 were respectively fitted based on the chroma- and hue-difference data of 16 non-neutral-color color centers from this study and RIT-Dupont datasets. The chroma and hue weighting functions of six CIELAB-based color-difference formulae together with SC_ZJU07 and SH_ZJU07 were compared, and the detailed analysis indicates that SC_ZJU07 and SH_ZJU07 perform best. For the chroma-difference data, the predicting performances of chroma weighting functions of all the six formulae are not good, while for the hue-difference data, the hue weighting functions of CIEDE2000 obviously outperform the others.