Development of a whiteness formula for surface colors under an arbitrary light source

Whiteness evaluation is essential in industries where surface color perception matters. Current methods rely on fixed light sources like D65, but real-world lighting varies. Earlier studies showed that adapting chromaticity using CAT02 improves whiteness prediction. However, these methods fail when comparing different correlated color temperatures. No prior work had resolved this limitation. Existing formulas cannot account for spectral differences across lighting conditions. This gap motivated the need for a universal whiteness formula. The study addresses this by proposing a new approach. The goal is to enable accurate whiteness assessment under arbitrary lighting.

The study aimed to develop a formula for evaluating surface whiteness under any light source. Current formulas only work under D65 lighting, which is insufficient for real-world applications. The researchers wanted to create a method that adapts to different correlated color temperatures. They focused on using chromatic adaptation to address this issue. The approach involved comparing samples under variable lighting conditions. The goal was to create a formula that remains consistent across lighting. The study tested eight samples under different light sources. The findings aim to improve whiteness evaluation accuracy in practical settings.

The researchers used a haploscopic setup with a D65 simulator on one side and variable lighting on the other. Eight samples were evaluated under different correlated color temperatures. Sample chromaticities were transformed using the CAT02 model. An adjusted chromatic adaptation factor D was introduced in the process. The D65 results served as a reference scale for comparison. The method involved measuring and comparing whiteness under each light source. The study focused on spectral content's impact on perceived whiteness. The approach combined experimental data with chromatic adaptation modeling.

The proposed formula uses the CIE whiteness formula with CAT02 chromatic adaptation. An adjusted adaptation factor D improved consistency across lighting conditions. The haploscopic setup revealed significant differences in perceived whiteness. The formula successfully predicted whiteness under varied correlated color temperatures. The D65 results provided a reliable baseline for comparison. The adjusted factor D allowed accurate scaling of chromatic adaptation. The method outperformed existing approaches in lighting variability. The results suggest a practical solution for real-world whiteness evaluation.

The study proposes a new formula for evaluating surface whiteness under arbitrary lighting. The formula uses CAT02 chromatic adaptation with an adjusted adaptation factor D. The haploscopic setup confirmed the method's effectiveness. The approach allows consistent whiteness evaluation across different correlated color temperatures. The D65 results provided a reliable reference for comparison. The formula addresses limitations in current whiteness formulas. The method improves accuracy in real-world lighting conditions. The findings suggest a practical solution for industries relying on precise whiteness assessment.