Matrox DigiSuite LE, Installation Manual, Page: 126 / 140

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Appendix B, DigiSuite Glossary
MPEG-1
See MPEG.
MPEG-2
A video compression standard that
improves upon the MPEG standard by supporting
data rates of up to 100 Mb/sec (12.5 MB/sec),
scalable modes, field or frame searching, and
much larger screen sizes. See also inter-frame (I-
frame) compression, intra-frame (IBP)
compression, 4:2:2P@ML, and MP@ML.
MPEG-2 IBP
An MPEG-2 compression type
that uses inter-frame compression to create a group
of I, B, and P-frames. See also GOP and inter-
frame compression.
MPEG-2 I-frame
An MPEG-2 compression
type that uses only intra-frame compression (that
is, only I-frames are created). See also intra-frame
compression.
multi-layer compositing
The process of
rendering a sequence that contains multiple layers
of realtime effects on DigiSuite for the purpose of
playing back the effects or saving them to an .avi
file. This type of rendering isn’t as fast as an
accelerated print-to-disk, but is faster than when
you render sequences containing software effects.
N
nonlinear editing
Random access editing that
generally uses video and audio clips stored on
disks. Nonlinear editing programs let you
rearrange and edit clips without having to redo the
entire production, and provide instant cueing to
any frame in a clip without waiting for tapes to
rewind.
NTSC
National Television Systems Committee.
The NTSC RS-170A standard defines a method of
broadcasting a color signal that can be received by
both monochrome and color TVs. It uses a
composite interlaced display comprised of 525
scan lines per frame, refreshed at a rate of
approximately 30 frames per second. Broadcast
systems in North America and Japan use the
NTSC standard.
P
PAL
Phase Alternate Line. A video standard that
uses a composite interlaced display comprised of
625 scan lines per frame, refreshed at a rate of 25
frames per second. This is the broadcast video
standard for most of Europe.
PCI retainer bracket
Bracket attached to
DigiSuite PCI cards with the function of extending
their length to line up with and be inserted in
standard ISA card guides.
PCI slot
Connection slot to a type of expansion
bus found in most Pentium-based computers. It is
smaller in size than older ISA slots and provides
connections to the high-speed PCI host bus.
P-frame (Predicted frame)
A frame created
during the MPEG or MPEG-2 IBP compression
process. A P-frame is created by using motion
vectors to predict the differences between it and
the closest previous I-frame or P-frame. This
forward prediction allows for higher compression
than with I-frames, but not as high as with B-
frames. P-frames, like B-frames, contain only
predictive data and therefore cannot be edited
independently. See also I-frame (Inter-frame) and
B-frame (Bi-directional frame).
pixel
Picture element. The smallest portion of
an image that can be written to a display. Each
pixel in an image represents a single dot on the
computer screen. A picture’s resolution depends
on the number of pixels on the screen. See also
pixel, square.
pixel, square
A pixel having equal width and
height. Graphics programs normally create images
with square pixels. NTSC and PAL video pixels,
however, are generally rectangular. This means
that graphics displayed on a TV screen will be
distorted (for example, a circle will display as an
ellipse), unless the pixel aspect ratio of the
graphics is adjusted to suit video. On DigiSuite
with the standard 4:3 screen format, NTSC pixels