By Ryo Nakagawa, Hiroyuki Shinoda and Yasuhiro Seya
Year 2013
Abstract
The extent of color constancy was examined by elementary color naming method. Subjects did color naming for three achromatic and forty chromatic Munsell color chips under three illuminants D, A, and A’ whose color temperature was lower than A. In the color naming task, subjects reported perceived components of whiteness, blackness, and chromaticness out of 100%. And then chromaticness was divided into red, yellow, green, and blue components following the color opponency rule. The results were plotted and the distributions were compared in a polar coordinate system where the chromaticness was taken as radius and hue (rate of red, yellow, green, and blue) as angle. The color constancy index was defined by overlapping area of distributions from two different illuminants. The index was higher, that is higher color constancy, between D and A than that of D and A.