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Kalypso Reference Manual
Section 3 — Menus
Matte Limiting
Matte Limiting determines how the matte generators produce colors.
Limits can be imposed to prevent downstream signal problems.
Decodable
– This limiter mode produces colors that decode to valid RGB
components. Not all valid RGB colors can be transmitted in NTSC, how-
ever. Saturated colors near yellow and cyan over modulate an NTSC trans-
mitter.
Transmittable
– This limiter mode prevents over modulating an NTSC trans-
mitter, but can produce colors which can not be decoded into RGB. For
example, a 0% luminance blue produces negative green and red compo-
nents.
Both
– This limiter mode is similar to
Decodable
, except that maximum levels
are reduced slightly around yellow and cyan to prevent over modulating
an NTSC transmitter.
None
– In this mode, no limiting is imposed. Analog signal paths and mon-
itors may behave poorly to some colors produced in this mode.
Default Transform Engine Crop
Default crops are intended to define the extent of a standard image for a
facility. The Default Transform Engine Crop controls adjust cropping when
individual Transform Engine channel crop is turned off. Individual Trans-
form Engine cropping is used to adjust for variations in individual sources.
SMPTE RP-187 establishes recommended practices for standard image
sizes (production aperture, clean aperture). If a facility conforms to these
practices, the Kalypso system default values will be correct and no adjust-
ment should be necessary. Changing the default crops is not recom-
mended, unless absolutely necessary.
Unfortunately, not all video images have the transition to blanking (black)
in exactly the same place. Normally, these blanking variations are hidden
at the extreme edges of the picture and are not visible. If an image smaller
than expected is transformed, however, black lines can occur at its edges,
which are now visible because they have moved inside the visible picture
area. If it is necessary to compensate for variations in your facility's
nominal blanking, adjust the default crops so they just remove black edges
on the facility’s normal image.
4:3 and 16:9 operation requires different default crops. The Kalypso system
is set at the factory with default crop values intended for 4:3 operation.
Aspect Ratio
Select the aspect ratio from
4:3
or
16:9
as desired.
