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...

When a color video system with highly accurate color reproduction is designed, a good measure is required for evaluating the image quality including the color reproduction. There are some degradation sources in a total imaging system from image acquisition to image reproduction. Color random noise is one of major degradations which is often added in image capture phase. In this paper, we invest...

The problem of gamut mapping is of interest in achieving an optimum color reproduction whenever a translation from one device (source) to another device (destination) is requested and the source gamut differs from destination gamut. For printing applications, if the ICC profile specifications are used, gamut mapping is applied to build the color tables that characterize the printing device. Wit...

Standardized in 1976 as a uniform color space, CIELAB is extensively utilized in color science and engineering applications. CIELAB provides both a color difference formula and correlates for common perceptual descriptors of color. Deficiencies in both areas are well-known, and based on these known limitations, numerous fixes have been developed yielding alternative color difference formulae th...

Due to the development and popularization of high-definition televisions, digital video cameras, Blu-ray discs, digital broadcasting, IP television and so on, it plays an important role to identify and quantify video quality degradations. In this paper, we propose SV-CIELAB which is an objective video quality assessment (VQA) method using a spatio-velocity contrast sensitivity function (SV-CSF)...

In 1931, the Commission Internationale de l’Eclairage (CIE) recommended a colour specification system. After various additions over the years it now includes a series of colorimetric measures such as the tristimulus values ( XYZ ), chromaticity coordinates, dominant wavelength, and excitation purity for colour specification and colour matching, CIELAB and CIELUV colour spaces for presenting col...

Color gamut mapping plays a crucial role in color management. Depending on the application, it is sometimes desirable to perform color gamut mapping by shifting the lightness and compressing the chroma of an out-of-gamut color while preserving the perceived hue of the color. The term Òperceived hueÓ is used to distinguish between the visual sensation of hue and metric hue angle (e.g., CIELAB hu...

Several color image delity metrics are evaluated by comparing the metric predictions to empirical measurements. Subjects examined image pairs consisting of an original and a reproduction. They marked locations on the reproduction that differed detectably from the original. We refer to the distribution of error marks by the subjects as image distortion maps. The empirically obtained image distor...

We describe a spatial extension to the CIELAB color metric that is useful for measuring color reproduction errors of digital images. To compute the error, digital color images are spatially ltered using a pattern-color separable method and then converted into the CIELAB representation. Over patterned regions of the image, the reproduction errors measured using the spatial extension of CIELAB co...