Color is commonly described in terms of the three perceptual attributes-hue, saturation, and brightness-of which only hue has a qualitative nature, saturation and brightness being of a quantitative nature. A possible reason for such a phenomenological structure of the color manifold, and its geometric representation, are discussed.

OBJECTIVE Cerebral dyschromatopsia is sometimes associated with acquired prosopagnosia. Given the variability in structural lesions that cause acquired prosopagnosia, this study aimed to investigate the structural correlates of prosopagnosia-associated dyschromatopsia, and to determine if such colour processing deficits could also accompany developmental prosopagnosia. In addition, we studied w...

Perceptual estimates can be biased by previously seen stimuli in delayed estimation tasks. These biases are often toward the mean of the whole stimulus set. Recently, we demonstrated such a central tendency bias in delayed color estimation. In the Bayesian framework of perceptual inference, perceptual biases arise when noisy sensory measurements are combined with prior information about the wor...

The lateral geniculate nucleus is thought to represent color using two populations of cone-opponent neurons [L vs M; S vs (L + M)], which establish the cardinal directions in color space (reddish vs cyan; lavender vs lime). How is this representation transformed to bring about color perception? Prior work implicates populations of glob cells in posterior inferior temporal cortex (PIT; the V4 co...

We describe a new color edge detection scheme and a related diffusion process based on hyperbolic coordinates in color space. We derive intensity, hue and saturation based edge detectors and show that the intensity and hue based diffusion processes are governed by the heat equation familiar from conventional scale space theory. A qualitatively new differential equation is derived for the satura...

A new color coordinate system, which describes color by means of brightness, hue and saturation, is presented. The relative distance from the body diagonal to the nearest surface of the RGB color cube is used as the saturation. The conversions from and to the RGB space are described. Keywords—colour coordinate system, brightness, hue, saturation

At the Budapest University of Technology and Economics in 1956, we decided to start large-scale experiments on color harmony. The experiments and the processing of the experimental data were completed in 2006. The experiments described in this article were based on a long established experience that harmony content of different hue pairs greatly differ from each other. The vast majority of form...

Color appearance can be studied using either Maxwellian-view optical systems or natural viewing (Newtonian-view). We show that the results are not precisely comparable when the natural pupil is appreciably larger than the entrance pupil of the Maxwellian beam. The wavelength for any given hue that is obtained from one viewing system is not the same as that obtained from the other viewing system...

A distinguished line-up of scholars recently got together to stir up discussion about the physiological basis for color and have, with a simple manipulation of decades-old data, challenged one of the fundamental tenets of our current understanding of the neurobiology of color (1). Understanding color is not easy. Newton made some headway, but his demonstration of color’s physical basis provided...