The following is a summary of “Dominating impacts of Helmholtz-Kohlrausch effect on color-induced glossiness enhancement,” published in the January 2023 issue of Ophthalmology by Koizumi, et al.
By including chromatic information in the object photos, glossiness may be improved. However, uncertainty existed about the processes that lead to color-induced glossiness augmentation. For a study, to clarify the perceptual and image variables that underlie the color-induced glossiness enhancement effect, researchers psychophysically assessed the glossiness of object pictures to which varied hue chromaticities had been added.
They investigated two different coloring scenarios: the both-colored (BC) condition, where both the specular and diffuse components were colored with the same chromaticity, and the diffuse-colored (DC) scenario, where the specular components were left achromatic. The findings demonstrated that glossiness enhancement was more pronounced in the BC condition compared to the DC condition, and its dependence on the color direction of the stimulus was comparable to that of the Helmholtz-Kohlrausch (H-K) effect. Additionally, they conducted a regression analysis using a linear mixed model based on picture attributes and a separate experiment where the luminance of achromatic stimuli was altered to mimic an increase in perceived brightness based on the H-K effect.
The outcomes showed that the glossiness improvement effect was effectively explained by the H-K effect-based brightness enhancement in the highlight areas. The findings implied that the color-induced glossiness improvement was mostly caused by the H-K effect, particularly in the highlighted area, while other color-related variables may also play a role.
Reference: jov.arvojournals.org/article.aspx?articleid=2785292