Operation Manual

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Last updated 10/4/2016
Chapter 13: Glossary
Glossary
3GP Third generation platform. A file format for video recorded by mobile phones.
16:9 The aspect ratio of widescreen TV.
AC3 See Dolby Digital .
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 .
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 .
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 .
audio lead See J-cut .
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.
AVI Audio Video Interleave. The standard, uncompressed video file format on the Microsoft® Windows® platform.
AV-to-DV converter An electronic device that converts analog video signals to digital video signals. Compare to DV-
to-AV converter .
bit depth In digital graphics and video, bit depth indicates the number of colors an image can display. A high-contrast
(no gray tones) black and white image is 1bit, meaning it can be off or on, black or white. As bit depth increases, more
colors become available. 24-bit color allows for millions of colors to be displayed.
Similarly, in digital audio, bit depth indicates the number of bits per sample. The higher the number, the better the
sound quality.
bitmap A graphic image comprised of individual pixels, each of which has values that define its brightness and color.