Adobe Premiere Elements 8 - Manual (Page 304)

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Last updated 8/12/2010
Chapter 18: Glossary
This glossary contains terms used for digital imaging technology. Some terms are specific to Adobe Premiere Elements
or other Adobe products.
Digital imaging terms
Numerics
16:9 The aspect ratio of widescreen TV.
3GP Third generation platform. A file format for video recorded by mobile phones.
4:3 The aspect ratio of conventional video recorded and played back by TV and computer screens.
A
AC3 See “ Dolby Digital ” on page 301.
ADC (Analog-to-Digital Converter) The hardware that converts an analog audio or video signal into a digital signal that
you can process with a computer.
AGP slot Accelerated graphics port slot. A connector on a computer’s motherboard for use with a GPU card. See
“ GPU ” on page 302.
aliasing Undesirable jagged or stair-stepped appearance of angled lines in an image, graphic, or text.
alpha channel Stores a matte (also known as a mask), which defines transparent areas of a computer graphic or clip.
Color information is stored in the three color channels, red, green, and blue (RGB). See also “ channel ” on page 300.
analog video Video that consists of a continuous electrical signal. Most TVs and VCRs are analog video devices. To
be stored and manipulated on a computer, analog video must be converted to digital video.
anti-aliasing The smoothing of edges in an image, graphic, or text. Anti-aliased edges appear blurred up close but
smooth at normal viewing distance. Anti-aliasing is important when working with high-quality graphics for broadcast.
artifact Distortion in a picture or a sound signal. With digital video, artifacts can result from overloading the input
device with too much signal or from excessive or improper compression.
aspect ratio The ratio of an image’s width to its height. For example, a standard video display has an aspect ratio of
4:3. Most motion pictures use the more elongated aspect ratio of 16:9. See also “ widescreen ” on page 308.
audio lead See “ J-cut ” on page 303.
audio sample rate The number of samples taken per second to reproduce audio digitally. The higher the sample rate,
the higher the quality of the digital audio. A rate of 44,100 samples per second produces CD-quality audio and captures
the range of human hearing.
AV-to-DV converter An electronic device that converts analog video signals to digital video signals. Compare to “ DV-
to-AV converter ” on page 301.
AVI Audio Video Interleave. The standard, uncompressed video file format on the Microsoft® Windows® platform.