A set of symmetric memory-matching data is presented to analyse some implications of long-term memory factors within classical colourconstancy paradigms and separation algorithms. Using simulated Mondrian-type colour surrounds on a CRT monitor, subjects make a series of colour matches between a test and a matching surface; the surfaces are rendered under the same standard illuminant (equal-ener...

The light reflected from an object depends not only on object colours but also on lighting geometry and illuminant colour. As a consequence the raw colour recorded by a camera is not a reliable cue for object based tasks such as recognition and tracking. One solution to this problem is to find functions of image colours that cancel out dependencies due to illumination. While many invariant func...

'The dress' is a peculiar photograph: by themselves the dress' pixels are brown and blue, colors associated with natural illuminants, but popular accounts (#TheDress) suggest the dress appears either white/gold or blue/black. Could the purported categorical perception arise because the original social-media question was an alternative-forced-choice? In a free-response survey (N = 1401), we foun...

Colour constancy is traditionally interpreted as the stable appearance of the colour of a surface despite changes in the spectral composition of the illumination. When colour constancy has been assessed quantitatively, however, by observers making matches between surfaces illuminated by different sources, its completeness has been found to be poor. An alternative operational approach to colour ...

In this paper, the results of an investigation of the possibility of extending "color constancy" to obtain illuminant-invariant reflectance features from data in the near-ultraviolet (UV) and near-infrared (IR) wavelength regions are reported. These features are obtained by extending a blackbody-model-based color constancy algorithm proposed by Ratnasingam and Collins [J. Opt. Soc. Am. A27, 286...

Color constancy is the perceived stability of the color of objects despite changes in the light illuminating them. An object's color is considered constant if the current perceived color is judged to be in accord with the remembered one. Thus the accuracy and precision of color memory are fundamental to understanding this classic problem. Two hypotheses of color memory are tested here: (1) the ...

For decades, photographs have often served as evidence in courts. One of the most common forms of photographic manipulation, known as image composition or splicing is analysed in this paper. The goal of blind image forensics is to distinguish original and manipulated images. We propose illumination color as a new indicator for the assessment of image authenticity. Many images exhibit a combinat...

For a color constant observer, the color appearance of a surface is independent of the spectral composition of the light illuminating it. We ask how rapidly color appearance judgments are updated following a change in illumination. We obtained repeated binary color classifications for a set of stimuli defined by their reflectance functions and rendered under either sunlight or skylight. We used...

In this paper we present a method that, given the tristimulus values under a known illuminant, make it possible to compute a reflectance function that is in the range between 0 and 1 of physically admissible values without altering the corresponding tristimulus values. We represent the unknown reflectance function with a three-dimensional linear model. 1. INTRODUCTION A common problem in spectr...

White balancing is a fundamental step in the image processing pipeline. The process involves estimating the chromaticity of the illuminant or light source and using the estimate to correct the image to remove any color cast. Given the importance of the problem, there has been much previous work on illuminant estimation. Recently, an approach based on ensembles of univariate regression trees tha...