Lightness modifications of the CIECAM16 and CIELAB based on the Helmholtz-Kohlrausch effect

This paper presents a variable-achromatic-color (VAC) lightness matching experiment conducted on a wide color gamut display. Based on the findings of this study, two models were proposed for the prediction of the Helmholtz-Kohlrausch (H-K) effect. The first method modifies High's hue-dependent function to account for the peak in red hues. The second method employs a lattice regression algorithm to construct a look-up table (LUT) based on the collected datasets. The model performance was evaluated by comparison with all other available H-K correction models and datasets. The results demonstrated that the two proposed models have achieved significant improvements in both the present and previous datasets.