Theoretical Prediction of Colours and Illuminants in sRGB Colour Space

Abstract

Photometric parameters and the evaluation of colour phenomena based on real human perception of light and colour were introduced into colour science in the first half of the 20th century. However, in the last two decades some known software programs for 3D computer graphics attempt to simulate realistic light source and optical effects with the help of photometric parameters. The reason for somewhat late arrival of such software applications can be found in the prevalent use of RGB colour space and the complexity of achieving realistic light source and colour
effects. The aim of the research was to write and implement a simple gamut compression algorithm that will make colour transformation from input XYZ data to appropriate RGB data of sRGB colour space within large number of colours (1872) and different illuminants (16), and also to define appropriate light source intensity in 3D modelling software to achieve optimal matching of simulated and real photographic lights with predefined RGB values. Due to discrepancies between real light sources and the interpretation of light source colours in 3D, RGB colours of
sRGB had to be adjusted with calibration procedure developed. The results of the research offer the possibility for theoretical prediction of virtual colours and light
source intensity for different colours of light sources.