The analysis of the Uniform Color System of the Optical Society of America (OSA-UCS) induces us to propose general hypotheses for defining color-opponency functions. The hypotheses are that the color signals is factorized into the product of the lightness with a pair of main chromatic opponency functions resulting from three processes: a linear transformation, a logarithmic compression and a chromatic opponency actuation. It results that the main chromatic opponency functions, individually with uniform scales, are equal to the logarithms of tristimulus-value ratios in a proper reference frame of the tristimulus space. The perceptual chromatic functions are a linear mixing of the main chromatic opponency functions. The performance of these hypotheses is successfully evaluated on the OSA-UCS system, for 10° visual field, and on the chromatic discrimination ellipses, for macular vision.
Claudio Oleari, "Chromatic Opponency: Hypotheses and Psychophysical Performance" in Proc. IS&T CGIV 2004 Second European Conf. on Colour in Graphics, Imaging, and Vision, 2004, pp 77 - 82, https://doi.org/10.2352/CGIV.2004.2.1.art00017