A general metric for the magnitude of observer metamerism

Abstract

Observer metamerism is defined as a property of a pair of spectrally different stimuli having the same colour sensation for an individual (reference) observer. Frequently, samples in this pair no longer match if the observer is changed. In this article, a linear approximation formula is developed that predicts a metameric effect caused by small changes in the observer's colour‐matching functions. This approximation formula enables a general metric of observer metamerism, the observer metamerism potential, to be defined that is independent of any particular deviated observer but still provides a close link to ‘observer‐metameric’ colour difference. Numerical experiments were conducted to investigate the correlation between the observer metamerism potential and the maximum of 53 metameric colour differences caused by the change from the colour‐matching functions of CIE standard 10° observer to the colour‐matching functions of 49 Stiles and Burch's real 10° test observers. The proposed general metric, together with a previous metric proposed by the present authors, the illuminant metamerism potential, could be taken as a quantitative measure of the performance of spectral approximation methods.

Appearance change for colored spun yarn fabric based on image color transfer

“…To avoid the influence of capture conditions, DigiEye system 17 was utilized for image capture. As shown in Figure 3(a), this system is equipped with a Nikon D7000 camera, special pick-up head and standard illumination D65, 18 which has the advantages of small color difference and stable capture condition. After capture, the image was cropped in the size of 1000 pixels  1000 pixels to reduce the parts of edge burr and platen, as shown in Figure 3(b).…”

Evaluation of Different Natural Dye Sources In Terms of Metamerism

“…For example, Sluban et al reported a general metric for the magnitude of observer metamerism. 6 In another study, Peyvandi et al reported the illuminant metamerism potentiality of metameric pairs. 8…”

“…The color of an object is a sensation rather than a particular property. 6 Metamerism is the name given to the phenomenon in which a pair of color stimuli, differing in spectral distribution, match in color under certain conditions, and not in others. 7 The degree of deviation from matching is known as the degree of metamerism and can be expressed by the metamerism index.…”

A study of spectral reflectance reconstruction using the weighted fitting algorithm based on the Sino Colour Book

“…Based on the above method, Xu et al 39 introduced a mixture of weights such that the selected training samples were about half the size of those in the method used by Cao et al The test yielded that using 100 training samples was sufficient. It ends up using less processing time than the method used by Cao et al In addition to this, Sluban et al 40 found that different observers cause different homochromatic heterospectral effects, so they proposed a linear approximation formula to solve this problem.…”