The structure and transformations of spectral color spaces are described. The approach applied for the spectral color spaces is data driven in the sense that the properties of the illumination sources and the reflectance properties of objects are of primary interest. Mainly three types of objects are considered in this approach including illumination spectra, reflectance spectra, and sensor sensitivity functions. It is found that under low-intensity illumination, a different definition has to be used. In the new coordinate system, one finds a good similarity between the Euclidean distance between two CIELAB vectors and the perceptual color difference between the corresponding colors for an average human observer.
2005. Vol. 138