Discrimination threshold of skin color in skin image

Abstract

　Skin color is an important factor related to judgment such as age, health condition, face impression, etc. It is very important to clarify its perceptual characteristics. Previous studies have reported that people show high sensitivity to changes in redness of the skin and that reddish skin looks brighter. From these facts, it is conceivable that people may recognize the skin and perceive the color of the skin. In this study, we focused on the relationship between the color distribution of skin color and color discrimination in particular. Principal component analysis was performed on the CIELAB value obtained by measuring the skin of 694 Japanese women and a color plane peculiar to the skin color composed of the first principal component and the second principal component was constructed. Then, the skin image and the monochromatic stimulus were modulated in eight directions on the plane, and the discrimination threshold was examined. We also examined the correspondence between the modulation direction and the change in the amount of melanin and hemoglobin which is the main pigment component consisting skin color. As a result, it was suggested that people have better discrimination for changes in color accompanying increase of hemoglobin.