Fairlight CVI, Руководство пользователя

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STE NCILS
The CYI can generate a 'live' stencil using the
Chromakey
feature. (See Section
3
- STENCIL SOURCE menu). The
chroma key stencil is generated continuously from the incoming
video signal, and is turned
On
where the picture is
blue
and
Off
i n all other areas. The
on
and
off
areas from the chromakey
stencil can be used to display two different pictures as with the
internal stencil. For example, if the i ncoming picture is of a
person dancing in front of a blue wall then the chromakey stencil
can be used to replace the 'blue wall' areas of the picture with
some other image, such as a picture from the field store. The
person then appears to be dancing against a background from the
field store.
The chromakey stencil is not stored in the CYI, but rather used
continuously for live stencil effects. The size, position and shape
of the chroma key stencil are determined entirely from the
incoming v ideo signal - they are
not affected
by PAN, ZOOM or
STRETCH. This allows the background to a chroma keyed figure
to be manipulated independently of the foreground.
The
In ternal
and
Chromakey
stencils can be used
simultaneously to generate a multi-plane effect known as
U n der­
over.
The CYI can also use a stencil generated by a n
External
source, or a stencil
Cascaded
from a second CYI. (See Section
3
-
STENCIL SOURCE menu for details.)
The shape of the stencil can be displayed at any time simply by
selecting
Show stencil
in the menus. (See Section 3 - Paint Menu
4).
When the DRAW STENCIL button is pressed the areas where
the stencil is turned
on
will be illuminated. This allows you to see
the shape of the stencil area before you use i t or as you draw it.
CVI DESCRIPTION
-
11