The International Color Consortium (ICC) has developed and refined a comprehensive and rigorous system for managing color. The CIE technical committee 8-01 has proposed a color appearance model for imaging applications. This paper describes issues that have to be considered when the CIECAM02 color appearance model is used within the framework of the ICC color management system. They concern dec...

The aim of the research was to establish an appropriate detection contrast metric in the mesopic luminance range which solves the problem of non-additivity by taking the influence of the chromatic channels into account. Based on several experiments at 10° and 20° eccentricity, and further theoretical modeling the CHC2 contrast metric was constructed, which takes the influence of the chromatic c...

The recently introduced detector-based calibration method for tristimulus colorimeters has been realized. The NIST reference colorimeter has been calibrated for spectral irradiance responsivity with an uncertainty of 0.15 % (coverage factor k=2) resulting in a chromaticity uncertainty of 0.0004 (k=2) in the x and y chromaticity coordinates when a CIE Illuminant A source is measured. The color s...

A general framework for anisotropic diffusion of multivalued images is presented. We propose an evolution equation where, at each point in time, the directions and magnitudes of the maximal and minimal rate of change in the vector-image are first evaluated. These are given by eigenvectors and eigenvalues of the first fundamental form in the given image metric. Then, the image diffuses via a sys...

The Preetham skylight model is currently one of the most widely used analytic models of skylight luminance in computer graphics. Despite its widespread use, very little work has been carried out to verify the results generated by the model, both in terms of the luminance patterns it generates, and in terms of numerical reliability and stability. In this paper, we show where the model exhibits p...

Surface metamerism is the phenomenon whereby two spectrally different reflectances induce the same response under fixed conditions (observer and illuminant) and induce different responses when recording conditions change. Metamerism arises due to the discrepancy between the degrees of freedom of the observer (usually three) and the degrees of freedom needed to represent surface spectral reflect...

In this paper the combination of texture and colour features is used for image classi cation. Texture features are extracted using the Discrete Wavelet Frame analysis. 2-D or 1-D histograms of the CIE Lab chromaticity coordinates are used as colour features. The 1-D histograms of the a; b coordinates were also modeled according to the generalized Gaussian distribution. The similarity measure de...

This paper is aimed to develop some new measures for quantifying colour rendering between a reference and a test illuminant. In addition, CIE colour rendering index (CRI) and Colour Quality Scale (CQS) were evaluated using different sets of testing samples in order to reveal whether the two measures are sample dependent or not.

The SGCK gamut mapping algorithm suggested by CIE TC8-03 has been enhanced by introducing a two-step procedure. Firstly, SGCK is used for gamut mapping the image onto a convex hull representation of the reproduction gamut. The resulting image is then further mapped onto a more realistic representation of the reproduction gamut using hue-angle preserving minimum ∆E∗ ab clipping. Panel testing wi...

For the first time, in the present study, a new approach of using the color properties of acid red 18 decolourization behavior by synthetized nano photocatalytic TiO2-Ag2O. In this manner two color system (CIE L*a*b* and CIE L*C*h°) used to calculate the color properties (lightness, Chroma and hue) of samples during the decomposition process. MATLAB software was used to transfer absorbance data...