CD Optical Storage Glossary of Computer Terms (Letter C)
Cache
Pronounced “cash”. An external or internal reserved portion of a computer’s electronic memory Random-Access Memory (RAM). Frequently used information is stored in the cache so that your computer can get the information more quickly.
CD
The 12cm (4.75 in.) optical read only disc used for digital audio, data, and video storage and retrieval in various computer, audio, and video systems. CDs are produced using a number of processes to store information for optical retrieval. see: WORM, WREN, CD-ROM
CD- DA Track
a track on a compact disc containing audio information encoded according to the CD-Digital Audio specific
CD-I
Compact Disc Interactive. An interactive audio/video/computer system developed by Sony and Phillips for the consumer market.
CD-ROM
Compact Disc Read Only Memory. An adaptation of CD technology for use with general digital data. CD-ROM discs are “pressed” in an injection molding process from a master mould to create the data tract. Then they are coated with a reflective material and sealed.
CD-ROM XA
Compact Disc Read Only Memory Extended Architecture. A format for recording compressed digital audio at lower qualities, allowing capacity increases on a single CD from four to 19 hours.
CD-RTOS
Kernel: the nucleus of CD-RTOS, which is responsible for service request processing, memory management, system initialization, multi-tasking, input/output management and exception and interrupt processing.
CD-RTOS
Compact Disc Real-Time Operating System. the name of the operating system used in CD-I players.
CD-WORM
Compact Disc Write Once Read Many times. A type of CD-ROM disc named for the process used to create data on the disc. CD-WORM Discs perform identically as CD-ROM discs. The difference being a laser is used to “burn” the reflective layer to create the data tract. The cost of ” WORM Burning” is considerably less than glass master production for a single disc.CD-WORM Disks can be used to transport CD-ROM s for mastering and replication.
CD-WREM
Compact Disc Write Read Erase Memory. A data storage system commonly referred to as “Magneto-Optical”. It incorporates laser technology to “Burn” a magnetic layer on the disc, this produces a reflective surface that can then be read. This magnetic layer can be burned many times giving the medium read, write, and write over capability not found in CD- ROM & CD-WREM. This advantage comes only with considerable cost for Drives and Disc Cartridges. As a result this technology has not caught on in the home consumer market. It has great potential for multimedia, pre-press publication, and other digital graphic applications.
chroma keying
facility to replace selected colors in a video image with others that allows the creation of different scenes against the background. Some video boards contain such capabilities.
Chrominance
signals of an image system that represent the color components of the image such as hue and saturation. A black and white image has chrominance value of zero.
Clipart
Stock digital images in various subject matter and format for use in multimedia productions or anywhere graphics are needed. Rights to use, pricing, and quality vary from one manufacturer to another.
Clone
To duplicate a portion of an image to another location. This is a cornerstone to the editing of digital images. This effect is useful in the process of retouching photographs.
CLUT
Color Look-Up Table. A table containing all the colors that may be used in a particular picture. Each entry provides an RGB value. The picture may then be encoded using the table entry addresses rather than the direct RGB value.
Color balancing
The process of tuning the overall color cast of an image or selection
Compressiona
digital process that permits data to be stored or transmitted using less than normal the number of bits. Compression is critical for displaying audio and moving video fast enough on desktop computers. Some compression standards for still images are formulated by JPEG, for moving video by MPEG, and for telecommunications transmission by CCITT.