Premium
Response of the human visual system to variable illuminant conditions: An analysis of opponent‐colour mechanisms in colour constancy
Author(s) -
Nieves J.L.,
Garcı´aBeltrán A.,
Romero J.
Publication year - 2000
Publication title -
ophthalmic and physiological optics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.147
H-Index - 66
eISSN - 1475-1313
pISSN - 0275-5408
DOI - 10.1046/j.1475-1313.2000.00471.x
Subject(s) - standard illuminant , color constancy , luminance , artificial intelligence , chromaticity , computer vision , chromatic adaptation , optics , mathematics , computer science , physics , image (mathematics)
Summary Illuminant changes in a scene generally cause displacements in the chromaticity and luminance of the objects of which the scene is composed; however, the visual system is capable of maintaining a constant object colour appearance independently of the illuminant. This is the phenomenon traditionally known as colour constancy. A classical asymmetric colour‐matching experiment is reported to address two aspects of colour constancy: successive colour constancy and the role of opponent mechanisms in it. To this end, colour matches are made with chromatically complex backgrounds under different illuminants and with an equal‐energy light source as standard. The results are analysed in the cone‐excitation space, separately along the L‐2M and S dimensions.Data are presented showing that colour‐vision mechanisms respond differently to illuminant changes when colour constancy is considered at both receptoral and post‐receptoral levels. The L‐ and M‐cones tend to adapt so as to support colour constancy, whereas S‐cones are strongly influenced by the illuminant changes. In addition, the data suggest good approaches to colour constancy linked particularly to the yellow‐blue mechanism.