What is the minimum amount of information we must transmit along with greyscale values in order to recover a colour original from a grey image? The problem of colour quantization is one of long standing with, for example, a GIF file consisting of single-byte grey values (appropriately compressed using entropy coding) plus a 256×3 colour lookup table in the file header. That lookup table can be ...

We propose a novel scanner characterization approach for applications requiring color measurement of hardcopy output in printer calibration, characterization, and diagnostic applications. It is assumed that a typical printed medium comprises the three basic colorants C, M, Y. The proposed method is particularly advantageous when additional colorants are used in the print (e.g. black (K)). A fam...

BACKGROUND Patients susceptible to periodontal disease and dental caries, including those who undergo fixed prosthodontic treatments use chemical plaque control agents. However, these mouthrinses may result in adverse effects such as discoloration of the restorative materials. The aim of this study was to compare the color stability of monolithic zirconia and feldspathic porcelain after immersi...

OBJECTIVES The purpose of this study was to investigate the difference in optical appearance of the soft tissues labial to dental implants and to analyze the effects of titanium implant neck colors transmitted through the marginal mucosa. MATERIALS AND METHODS Fourteen patients with 15 Straumann single implant replacements in the maxillary anterior region were recruited. Color measurements of...

A common need of the INCITS W1.1 Macro Uniformity, Color Rendition and Micro Uniformity ad hoc teams is to digitize image quality test targets and derive parameters that correlate with image quality assessments. The digitized data should be in a colorimetric color space such as CIELAB and have no spatial artifacts that reduce image quality parameter accuracy. Input digitizers come in many forms...

Corresponding Author: Dr. Gabriele Corciolani, Via Derna 4, 58100 Grosseto (Italy) E-mail: [email protected]; Tel/Fax: +39056425384 Abstract Objectives: The aim of this study was to evaluate the repeatability of readings with a clinical spectrophotometer in comparison with a laboratory one. Materials and Methods: A stand alone clinical spectrophotometer (Easyshade, Vita) and a labor...

An ecological approach has been obtained by using natural dyes and mordant for dyeing process. Fabrics dyed using myrobalan extract as natural mordants and green dye. A red color were obtained by using theses mordants. The color of dyed fabrics was investigated in CIELab L, a and b and K/S values. Finally, all dyed fabrics were tested for wash and light fastness properties as per ISO standard t...

©2002, IS&T—The Society for Imaging Science and Technology be difficult to apply conventional color halftoning techniques to high-fidelity color printing. In a blue noise halftoning method, the problems related to Moiré patterns in conventional screen designs are replaced by color image quality issues related to the overlay of blue noise patterns. A number of different schemes have been propose...

Spectroradiometric color measurements were performed at 26 regularly spaced points of a standard wine sampler into which 100 cc of wine were poured. Our goal is to describe the color changes occurring in this system, but not to propose a new method for wine-color measurement. Three samples of three different wines (red, rosé and white) were studied. From experimental measurements, lines of cons...