The measured light spectrum is the result of an illuminant interacting with a surface. The illuminant spectral power distribution multiplies the surface spectral reflectance function to form a color signal--the light spectrum that gives rise to our perception. Disambiguation of the two factors, illuminant and surface, is difficult without prior knowledge. Previously [IEEE Trans. Pattern Anal. M...

Does extending the number of channels from the 3 RGB sensors of a colour camera to 6 or 9 using a multispectral camera enhance the performance of illumination-estimation algorithms? Experiments are conducted with a variety of colour constancy algorithms (Maloney-Wandell, Chromagenic, Greyworld, Max RGB, and a Maloney-Wandell extension) measuring their performance as a function of the number of ...

Abstract. In accordance with the “Declaration of Rome on architectural survey”, we can affirm that recording and interpretation colour information in photographic surveying, photogrammetric surveying photomodelling requires careful planning Colour Imaging processes. Information acquired by an optical sensor is influenced not just actual photographed scene, but also spectral sensitivity sensor. ...

Received September 5, 1991; revised manuscript received October 30, 1991; accepted November 13, 1991 Viewing the lights reflected by a set of three or more surfaces, a trichromatic visual system can recover three color-constant descriptors of reflectance per surface if the color of the surfaces' illuminant changes. This holds true for a broad range of models that relate photoreceptor, surface, ...

The presence of highlight can lead to erroneous results in Computer Vision applications such as edge detection, and motion tracking. Many algorithms have been developed to detect and remove highlight. In this paper, we propose a simple and effective method for detecting and removal of highlight. We first use a window to help to remove the noise and reduce the data amount for analysis. We then a...

Many models of color constancy assume that the visual system estimates the scene illuminant and uses this estimate to determine an object's color appearance. A version of this illumination-estimation hypothesis, in which the illuminant estimate is associated with the explicitly perceived illuminant, was tested. Observers made appearance matches between two experimental chambers. Observers adjus...

In this paper, we present a novel dichromatic-based method for estimating illuminant chromaticity. The proposed method is essentially based on the Dichromatic Slope and Dichromatic Line Space that we introduce. Dichromatic slope is the slope of the dichromatic line that passes the image chromaticity of a pixel in chromaticity space. It is specularity-invariant and can be computed for each pixel...

Relational color constancy, which refers to the constancy of perceived relations between surface colors under changes in illuminant, may be based on the computation of spatial ratios of cone excitations. As this activity need occur only within rather than between cone pathways, relational color constancy might be assumed to be based on relative luminance processing. This hypothesis was tested i...

A new multilinear constraint on the color of the scene illuminant based on the dichromatic reflection model is proposed. The formulation avoids the problem, common to previous dichromatic methods, of having to first identify pixels corresponding to the same surface material. Once pixels from two or more materials have been identified, their corresponding dichromatic planes can be intersected to...

Information about the illuminant color is well contained in both achromatic regions and the specular components of highlight regions. In this paper, we propose a novel way to achieve color constancy by exploiting such clues. The key to our approach lies in the use of suitably extracted derivative colors, which are able to compute the illuminant color robustly with kernel density estimation. Whi...