User guide

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Glossary of terms
on the clip until a later keyframe is defined to
turn off or change the settings. See also
interpolate.
L
LTC Longitudinal Time Code. Time code
that is generally encoded as an audio signal
onto a linear audio track of a tape. This type
of time code can be read only while the tape is
moving. See also VITC.
linear interpolation One of the two types
of interpolation that can be set between
consecutive keyframes using the Matrox
realtime plug-in. Linear interpolation means
that the transition between effect settings
occurs in even, linear increments. See also
spline interpolation.
luma key An effect that makes portions of
a foreground image fully or partially
transparent based on the luminance of that
image, so that an underlying image can show
through. See also alpha key and chroma
key.
luminance The brightness portion of a
video signal. The luminance of a pixel
determines its brightness on a scale from
black to white. See also chrominance.
luminance key See luma key.
M
mark in To select the first frame of a clip.
mark out To select the last frame of a clip.
mask DVE effect A Matrox effect that
uses a moving grayscale pattern (matte) to
superimpose one clip onto another. Also
called traveling matte effect.
MIP mapping In 3D graphics, a rendering
technique where a texture is stored at multiple
resolutions. See also texture mapping.
M-JPEG See Motion-JPEG.
Motion-JPEG A compression and storage
standard used for motion video. The JPEG
compression process is applied to each video
field, in succession. Also called M-JPEG.
MP@ML Main Profile@Main Level. An
MPEG-2 video compression profile that
supports 4:2:0 luminance/chrominance
sampling at up to 720×576 pixel resolution,
and data transfer rates up to 15 Mb/sec (1.79
MB/sec). This profile is used for broadcast
transmission and distribution on DVD. See
also 4:2:2P@ML.
MPEG A video compression standard that
specifies a series of compression profiles and
image resolution levels, introduced in 1990 by
the Motion Picture Experts Group. MPEG
takes advantage of the redundancy inherent in
video data through a combination of inter-
frame and intra-frame redundancy reduction.
The MPEG standard supports data transfer
rates of up to 1.5 Mb/sec (0.2 MB/sec). Also
called MPEG-1. See also MPEG-2, inter-
frame (IBP) compression, and intra-frame (I-
frame) compression.
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
MB/sec), scalable modes, field or frame
searching, and much larger screen sizes. See
also intra-frame (I-frame) compression, inter-
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. Used for
broadcast transmissions and distribution on
DVD. See also GOP.
MPEG-2 I-frame An MPEG-2
compression type that uses only intra-frame
compression (that is, only I-frames are
created). Used for high-quality distribution
and for archiving.