User guide

273
Glossary of terms
only predictive data (that is, not enough data
to make up an entire picture), and therefore
cannot be edited independently.
BIOS Basic Input/Output System settings
for system components, peripherals, etc. This
information is stored in a special battery-
powered memory and is usually accessible for
changes at computer start-up.
bitmap A graphics image in which a set of
values defines each pixel’s relative brightness
and color.
Blue Book standard See DV.
black level The level of brightness at
which no light is emitted from the screen
(reference black). The standard black level is
7.5 IRE for NTSC video, or 0 IRE for NTSC-
EIAJ (Japan) and PAL video. Also called
setup (NTSC video only). See also white
level, super black, and super white.
blur effect A Matrox effect that uses
various levels of intensity to blur an image.
bus A shared set of hardware lines that lets
different parts of your computer transfer
information between one another. A card
inserted into an expansion slot of your
computer makes an electrical connection to
the bus and effectively becomes part of your
computer system.
C
capture The process of digitizing video or
audio material, usually from a VTR or
camera, and storing it in a file on a hard disk.
chroma key An effect that makes portions
of a foreground image fully or partially
transparent based on the color of that image,
so that an underlying image can show
through. See also alpha key and luma key.
chrominance The color portion of a video
signal that carries the hue and saturation
information. See also luminance.
codec Compressor/decompressor. A
processor that compresses video to reduce its
file size by eliminating redundancies in
information. It also decompresses files to play
them back.
color bars A standard test signal that
appears as a series of vertical rows of color by
which the chrominance and video levels of a
camera’s output or a recorded signal can be
checked.
color correction effect A Matrox effect
that allows various color properties of an
image to be adjusted. There are controls for
adjusting the intensity level for hue,
saturation, contrast, and brightness. The color
correction effect can correct improper color
levels of an image that are due to varying
lighting conditions or incorrect camera
settings. See also white balancing.
compile See render.
component video A video signal having
separate channels for the video information,
as opposed to a combined (composite) signal.
Y, R-Y, B-Y video is a component video
signal.
composite video A video signal
containing luminance and chrominance
information that has been combined using a
video standard such as NTSC or PAL.
Composite video often uses a single RCA or
BNC cable connection. See also component
video.
contrast The difference in brightness
between the lightest and darkest areas of an
image on the screen.
CPU-based effect An effect that takes
advantage of your computer’s CPU to play
back in real time. The Matrox color correction
effect is an example of a CPU-based effect.
Compare with hardware-accelerated effect.
crawl Sideways movement of text across a
screen. See also roll (1).