Color constancy is something we take for granted. An apple appears red despite monumental changes in the intensity and spectral balance of illumination. There are many components to human visual system that make this illusion possible. Nonetheless, imperfect. Objects will change apparent color under different The CIELAB space allows computation values any illuminant. will, general, as illuminan...

The sizes for the perceptible or acceptable color difference measured with instruments vary by factors such as instrument, material, and color-difference formula. To compensate for disagreement of the CIELAB color difference ( E*ab) with the human observer, the CIEDE2000 formula was developed. However, since this formula has no uniform color space (UCS), DIN99 UCS may be an alternative UCS at p...

Color gamut characterization is an essential step in the ICC profile generation for imaging devices. It is also needed as part of evaluation and comparison of image quality achievable by different imaging systems. A novel technique is presented for characterizing the color gamut of an imaging device via ray tracing in the CIELAB color space. Initially, the convex hull of the set of measurement ...

objective: propolis is a resinous material produced by honeybees that has recently gained fame as an antimicrobial agent. this study sought to assess the effects of propolis as an intra-canal medicament on tooth discoloration. the effect of its application technique on the degree of discoloration was investigated as well. methods: this experimental study was conducted on 40 intact anterior huma...

color match between fiber-reinforced composite (frc) restorations and teeth is an imperative factor in esthetic dentistry. the purpose of this study is to evaluate the influence of veneering composites and fibers on the color change of frc restorations.glass and polyethylene fibers were used to reinforce a direct microhybrid composite (z250, 3m espe) and a microfilled composite (gradia indirect...

CIELAB is commonly used in design as it provides a simple method for approximating color difference. However, these approximations model color perception under laboratory conditions, with correctly calibrated displays and carefully constrained viewing environments that are not reflective of complexity of viewing conditions encountered in the real world. In this paper, we present a data-driven e...

The RIT–DuPont visual color-difference data as the RIT–DuPont data set, and they are the basis for [Color Res. Appl. 16, 297–316 (1991)] have been used our current analyses. to estimate contours of equal color-differences (ellipThe RIT–DuPont data set consists of 156 tolerances, soids) at 19 color centers, in CIELAB and x , y , Y /100 each of equal visual color difference, DV . Nineteen color c...

A large scale psychophysical experiment was carried out to judge the perception of image quality of the photographic images. Two types of experiments, pair comparison and categorical judgment, were conducted for evaluating image difference and absolute quality respectively. Test images were generated by rendering the eight selected original images according to the change of lightness, chroma, c...

In this study, we evaluated the effect that pixel size has upon people’s preferences for images. We used multispectral images of faces as the scene data and simulated the response from sensors with different pixel size while the other sensor parameters were kept constant. Subjects were asked to choose between pairs of images; we found that preference judgments were primarily influenced by the v...