Using a paired comparison paradigm, various gamut mapping algorithms were evaluated using simple rendered images and artificial gamut boundaries. The test images consisted of simple rendered spheres floating in front of a gray background. Using CIELAB as our device-independent color space, cut-off values for lightness and chroma, based on the statistics of the images, were chosen to reduce the ...

PURPOSE We developed a new artificial image enhancement system aimed at intraoperative visibility improvement as a clinical prototype. We examined each optical characteristic and change in intraoperative visibility using brilliant blue G (BBG) staining with various sharp cut filters (SCFs). METHOD This was a retrospective and observational study. The system was composed of several filters att...

For precision color matching, visual sensitivity to small color difference is an essential factor. Small color differences can be measured by the just noticeable difference (JND) ellipses. The points on the ellipse represent colours that are just noticably different from the colour of the centre point. Mathematically, such an ellipse can be described by a positive definite quadratic differentia...

Studying color preferences provides a means to discover how perceptual experiences map onto cognitive and affective judgments. A challenge is finding a parsimonious way to describe and predict patterns of color preferences, which are complex with rich individual differences. One approach has been to model color preferences using factors from metric color spaces to establish direct correspondenc...

Two criteria for selecting ink sets for six-color lithographic printing are discussed. The first is the volume, in CIELAB space, of an approximation of the gamut. The second is the number of pixels within a digital image (or images) whose colors are contained within the approximate gamut. In order to obtain a balance between accuracy and efficiency, the different steps in the process are priori...

OBJECTIVES To study the color stability of dental composite resins using a thermocycling stain challenge model accounting for the complex effects of oral environment and tooth brushing. METHODS Composite resin discs were made from Filtek Supreme Ultra (FiltekSU), TPH3 and Renamel, and subjected to thermocycling challenges in warm coffee (55 °C/pH 5.2) and a cold tea and fruit juice mixtures (...

OBJECTIVE Evaluate the immediate and cumulative optical whitening efficacy of a blue covarine toothpaste. MATERIALS AND METHODS 180 bovine tooth specimens with similar shade (ΔE < 3.5) were staining of different beverage: black tea(BT), green tea (GT), red wine (RW), orange soda (OS), and brazilian açai juice (AJ), and then submitted to tooth brushing with a blue covarine toothpaste (Op) or a...

bstract. We propose a novel scanner characterization approach or applications requiring color measurement of hardcopy output in alibration, characterization, and diagnostics applications. The ethod is advantageous for common practical color printing sysems that use more than the minimum of three colorants necessary or subtractive color reproduction; printing with cyan (C), magenta M), yellow (Y...

A colorimetric modeling technique is proposed to give a computational model associated with colorimetry so that the representation of color acquired from camera imaging is accurate and meaningful. First of all, the camera spectral responses are estimated and the colorimetric quality is evaluated to reveal the feasibility of this work. In the modeling process, we present a spectral matching meth...

Ten colour emotional scales, namely, "Warm Cool", "Active-Passive", "Like-Dislike", "Clean-Dirty", "Fresh-Stale", "Modern-Classical", "Heavy-Light", "Hard- Soft", "Tense-Relaxed", and "Masculine-Feminine"are investigated for single-colour stimuli in CIELAB colour space within a psychophysical experiment by forty observers. The relationships between Iranian colour emotional responses and CIELAB ...