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Luma Keying
As well as being a Chroma Keyer the DVK-200 can also be used as a Luma Keyer. A Luma Keyer can key
out luminance values. In simple terms this means you can key either with the Black end of the grey scale, or
the White end of the grey scale. If for example you have an image on a white or black background it is
possible to use Luma Keying to replace the black or white area with another video source. Here is an
example based on Luma keying with a Black Matte.
Foreground DVI-I supplied Image
with Black Matte Area
Background Y/C or CV Video
Luma Keyed Image with
Background Video showing
through the Black Matte Area
Luma Key Installation
The following Luma Key overlay installation offers a number of possibilities. Please bear in
mind that, despite their name, GREEN and BLUE, these keys do not necessarily have any
reference to the connected Foreground or Background video inputs in a Luma Key set up.
Whichever key is lit this is the active Luma Key channel that you are working with. Although
later in this manual we suggest setting up these buttons for keying out a white or black area.
For this set up you will need a computer fitted with a graphics card that can support two DVI-I connections at
a resolution of 1024x768. DVI-I Connection 1 will go to the computers own monitor and connection 2 will go
to the DVI-I input on the DVK-200. Ensure the CAM input selection switch on the DVK-200 rear panel is
moved to the DVI position.
A live camera view or recorded video source is then connected via the background S video or composite
video connector. Ensure the BG (Background) input selection switch matches the video BG input connection
being used.
Using the attached computer monitor extend the desktop of the computer to the second monitor (in this set
up the DVK-200 acts as the second monitor). Set the second monitor output resolution to match 1024x768.
This second monitor output from the computer will then be seen by the DVK-200 DVI-I input.
Open up PowerPoint on the PC and use
Set Up Show
so that the presentations play back on Monitor 2 (the
DVK-200) and the presentator’s output is sent to Monitor 1 (the PC’s own monitor).
