Matrox Axio Installation And User Manual page 321

I-frame compression See MPEG-2 I-
frame.
I-frame (Intra-frame)
during the MPEG or MPEG-2 compression
process that contains all the information
required to reproduce a complete image. It
allows random access points within a video
stream, and acts as a reference point for B-
frames and P-frames to be built. I-frames are
editable because they contain enough data to
construct an entire video frame, unlike B-
frames or P-frames.
impressionist effect A Matrox effect that
lets you choose from many different patterns
to make your image appear similar to an
impressionist painting.
IMX
A video recording format developed
by Sony, and standardized by SMPTE as D10,
that is used to record video and audio onto a
hard disk or tape. The IMX data format is
fully MPEG-2 compliant and supports video
data rates of 30, 40, and 50 Mb/sec. Video is
sampled at 4:2:2 for both NTSC and PAL
sources.
insert editing Recording new video
and/or audio material onto a prerecorded (or
striped) tape. Insert edits can be made in any
order, unlike assemble edits, which must be
made sequentially.
inter-frame compression A video
compression method that compares a series of
frames in a video sequence and removes the
redundant data. Inter-frame compression
treats all the frames in the sequence as an
interdependent group. As a result, most of the
frames can't be edited independently. Also
called temporal redundancy reduction.
Contrast with intra-frame compression. See
also GOP.
interlaced scanning A method of
creating a video image by drawing only the
odd numbered lines on the screen in one pass,
A frame created
then the even numbered lines in the next pass.
Two passes are therefore required to create a
complete frame of video. NTSC and PAL
displays are interlaced. See also progressive
scanning.
interleave A technique used to incorporate
the video and audio portions of a video clip
into one file. See also AVI.
intra-frame compression A video
compression method that removes redundant
information from within a frame. Intra-frame
compression treats each frame of a video
segment independently. Several video
compression formats use the intra-frame
method. These include Motion-JPEG, DV,
and MPEG-2 I-frame. Also called spatial
redundancy reduction. Contrast with inter-
frame compression. See also I-frame (Intra-
frame).
IRE unit
An arbitrary unit designated by
the Institute of Radio Engineers to define the
amplitude of a video signal. 1 IRE is equal to
approximately 7 mV.
J
JPEG (pronounced "jay-peg") Joint
Photographic Experts Group. A compression
and storage standard used for still, digital
images. See also Motion-JPEG.
K
key effect See alpha key, chroma key, and
luma key.
keyframe A particular frame at which one
or more effect settings have been defined.
Settings applied at a keyframe remain active
on the clip until a later keyframe is defined to
turn off or change the settings.
L
lens flare effect A Matrox effect that lets
you choose from many different patterns to
simulate the light refractions caused by
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Glossary of terms