Contex SD One+ - Page 56

Service Guide SD One+ 56
CCD:
Charge Coupled Device, CCD is the image sensor in the scanner that converts light to voltages. These voltages are
converted by the scanner into the image.
CCITT Group3:
Standard run-length compression format used with FAX transmission. It utilizes modified Huffman
coding to further compress the run-length numbers. Most scanner file formats are dialects of this format.
CCITT Group4:
Two-dimensional compression format, giving very compact image files. Standardized by CALS (MIL 28002) and ISO-
ODA for Drawing Archival and Interchange.
CIE LAB:
A device-independent color space specified by CIE, used in modern color management software to facilitate
conversion of data from a scanner to a display, or from a display to an output device.
CIE:
Centre Internationale d’Eclairage (CIE) is an international organization that establishes methods for measuring color.
These color standards for colormetric measurements are internationally accepted specifications that define color
values mathematically. The first color space model, the CIE xyz, was developed in 1931. CIE defines color as a
combination of three axes: x, y,and z. The two color spaces released in 1978 are CIE Lab and CIE Luv. The goal was
to provide an accurate and uniform reference of visual perception.
CMYK:
The subtractive printing colors. Cyan, Magenta, Yellow, Black.
Color Balance:
The visual effect of an image when the amount of each color and the overall amount of color are balanced.
Color bit depth:
The simplest pixel has two options: black or white. (A pixel with two choices is known as a 1-bit image, or two raised
to the power of one). Adding more bit information increases the number of color options. The number of potential
color options for a pixel is called color bit depth. For example a 4-bit pixel would have 16 color options, and an 8-bit
pixel would have 256 color options, while a 24-bit pixel would have 16,777,216 color options.
Color Cast:
An image is said to have a color cast if its colors are not true. A color cast will usually be described by stating the
particular color predominant in the image, e.g., the grass appears to have a red color cast.
Color Correction:
To improve the color rendition. Correcting for, and eliminating an unwanted color cast.