Matrox DigiSuite LE, Installation Manual, Page: 120 / 140

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Appendix B, DigiSuite Glossary
Use this glossary as a reference for many of the
basic terms in the DigiSuite manuals.
Numerics
1394
See IEEE-1394.
4:2:2P@ML
4:2:2 Profile@Main Level. An in-
ternational standard video compression profile
introduced by MPEG-2. It supports 4:2:2
luminance/chrominance sampling at up to
720×608 pixel resolution, and data transfer rates
up to 50 Mb/sec (6.3 MB/sec). This profile is used
for high-quality distribution and for archiving. See
also MP@ML.
A
A/B roll
Typically, A/B roll is an editing
technique where scenes or sounds on two source
reels (called roll A and roll B) are played
simultaneously to create dissolves, wipes, and
other effects. On nonlinear editing systems, A/B
roll refers to using two source streams (.avi, .wav,
.tga, and so on) to create an effect.
accelerated print-to-disk
The process of
rendering to an .avi file a realtime sequence of
effects on DigiSuite (excluding Inscriber/CG
rolling and crawling titles). This is the fastest type
of rendering available on DigiSuite. See also
multi-layer compositing.
aliasing
A display characteristic of computer-
generated text or graphics that appears as jagged
or stair-stepped edges on diagonal lines. See also
anti-aliasing.
alpha key
An effect that makes parts of a
foreground image fully or partially transparent
based on alpha (transparency) values stored within
the image’s file, so that an underlying image can
show through.
analog component video
See component
video.
analog signal
A video or audio signal that
varies continuously, as opposed to a digital signal
which varies only by fixed steps.
anti-aliasing
A technique that smooths jagged
edges in computer-generated text or graphics.
aspect ratio
A width-to-height ratio. For
example, a 12-by-9-inch image has an aspect ratio
of 4:3 (four-to-three). Most TV screens have a 4:3
aspect ratio. HDTV screens have a 16:9 aspect
ratio. See also pixel, square.
assemble editing
Recording new video and
audio material sequentially onto tape. Because all
the signals are recorded (video, audio, and control
track), the new material completely replaces any
previously recorded material on the tape. See also
insert editing.
attenuation
A decrease in an electrical
signal’s amplitude.
A/V drive
SCSI hard drive capable of storing
high-bandwidth audio/video data.
B
backplane
PCB (printed circuit board) on a
Movie-2 bus connector.
base board
Printed circuit board (and
mounted components such as integrated circuits,
etc.) that is inserted into the computer's expansion
slot. A module board is often attached to the base
board.
B-frame (Bi-directional frame)
A frame
created during the MPEG or MPEG-2 IBP
compression process. A B-frame is generated by
forwards and backwards referencing of the P-
frames and I-frames respectively, which allows it
to have the highest compression ratio of the three
frame types. B-frames contain only predictive
data (that is, not enough data to make up an entire
picture), and therefore cannot be edited
Glossary of terms