Glossary

Vocabulary that holds the terms for the vocabulary.

a
Analogue Component Videosearch for term

Refers to a standard consisting of analogue video signals transmitted on three wires, one for luminance (Y), one for the red component from which is subtracted the total luminance (R-Y), and one for the blue component from which is subtracted the total luminance (B-Y). (The green component is derived by combining the three components described.) The designations Y/Pb/Pr and Y/Cb/Cr are also used to stand for analogue component video where more correctly the latter is for digital video. The so called "component video" jack or jacks seen nowadays are for analogue component video. See, also, Component Video.

Analogue signalsearch for term

A continuous signal that requires time to make a transition from one level to another. Standard audio and video signals are analogue. Both can be digitised. The video in the laserdisc format is analogue composite. The audio can be present in both analogue and digital forms. Both the audio and video on DVD has been recorded on the disc in the digital domain.

Anamorphicsearch for term

Process that horizontally condenses (squeezes) a 16:9 image into a 4:3 space, preserving 25 percent more vertical resolution than letterboxing into the 4:3 space. For the signal to appear with correct geometry, the display must either horizontally expand or vertically squish the image. Used on about two or three promotional laser discs and many DVDs. Also called Enhanced for Widescreen or Enhanced for 16:9.

ANSIsearch for term

Acronym for American National Standards Institute; co-ordinates the development of U.S. voluntary standards in both the public and private sectors. ANSI has established the standard followed by projector manufacturers for measuring lumen brightness.

Artifactsearch for term

In video, refers to something present in the reproduced image, notably crawling dots, rainbow swirls, and color contamination, and that was not present in the original picture or scene. Artifacts are the result of imperfect capture, processing, transmission, storage, and/or decoding of the video signal.

Aspect Ratiosearch for term

The ratio of image width to image height. Common motion-picture ratios are 1.85:1 and 2.35:1. Television screens are usually 1.33:1 (also known as 4:3), which is similar to the Academy standard for films in the '50s. HDTV is 1.78:1, or 16:9. When widescreen movies (films with aspect ratios wider than 1.33:1) are displayed on 1.33:1 televisions, the image must be letterboxed, anamorphically squeezed, or panned-and-scanned to fit the screen.

ATSCsearch for term

Advanced Television Systems Committee. Government-directed committee that developed our digital television transmission system.