A new inter-color distance based on color to planar shape mapping

Although simple and based on physical realizable color primaries, the RGB color space cannot allow the direct definition of a topology-preserving, perceptually-compatible inter-color distance. The classical normalized inter-color distances are rather complex to implement and tune. We propose the use of a planar color representation plot, derived from multivariate data visualization, which allows the introduction of a luminance-invariant, geometry-based inter-color distance, used with good results in the implementation of distance-based color filters.