CIELAB与CIECAM02色空间均匀性比较研究

采用均匀色空间Munsell系统检验和验证了CIELAB和色貌模型CIECAM02色空间的均匀性。利用Mun- sell色卡所对应的三刺激值X,Y,Z作为模型的输入值,预测色空间模型的明度、彩度和色调,并通过预测结果比较和检验了CIELAB色空间和CIECAM02模型色空间的均匀性。研究表明:在预测明度方面,两个色空间的结果相似;在预测彩度时,CIECAM02模型较好于CIELAB色空间;在预测色调时,当色调逐渐从BG变化到B时,CIELAB所预测的色调角与由Munsell色空间计算出来的色调角之差逐渐增大,最大时超过6%,而CIECAM02所预测的色调角与Munsell色空间的色调角之差在2.5%以内,CIECAM02优于CIELAB色空间。

Uniform comparison between CIELAB color space and CIECAM02 color space

The uniform color space Munsell system is used for proving the uniformity of CIELAB color space and CIECAM02 color space.Tristimulus value(XYZ)is calculated by xy and Y of Munsell patch measured by CIE under C illumi- nation.X,Y and Z are used as input to predict lightness,chroma and hue of color appearance model.Utilizing the predictive result compares and proves the uniformity of CIELAB color space and CIECAM02 color space.From the result of study, CIELAB and CIECAM02 model have a similar result aspect of lightness,by predicting chroma,CIECAM02 model is preferable than CIELAB model,but comparing the hue uniformity of the model,there is a considerable improvement for CIECAM02,es- pecially for the blue area.There is a bigger angle difference between hue angle calculated by Munsell color space and calculated by CIELAB space when hue angle changes from BG to B gradually.The biggest difference Exceeds 6 %.But between Munsell space and CAM02 space,the difference is less than 2.5 %.