User guide

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Chapter 6, Setting Up Realtime Effects with Adobe Premiere
Overview of the chroma key effect
You can use the Matrox realtime plug-in to apply a chroma key to make certain
areas of a foreground video clip transparent based on a color in that image, so
that an underlying video clip can show through.
In the following example of a chroma key effect, our foreground image is a video
clip of a woman sitting in front of a green backdrop, and our underlying image is
a video clip of a sand dune:
By chroma keying on the particular shade of green in the backdrop of the
foreground image, the backdrop area becomes transparent and the corresponding
area of the underlying image shows through in the composite image as follows:
¡ImportantYou must apply the Matrox chroma key effect to the clip that
contains the colors on which you want to key (that is, your foreground image on a
superimpose track). To create a realtime chroma key effect, both the foreground
and underlying images must be video clips. If you want to use a graphics clip,
you can export that clip from the Timeline to a single-frame .avi file, then replace
the graphics clip on the Timeline with your exported file.
Foreground image
Underlying image
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Result of chroma key
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