+ useful when you only want a specific zone defined.
+ .
+ Color button is used to specify the key by color.
+ Threshold slider is used to set tolerance (0-1).
+ Key mode choices let you pick the method by which
+ the chroma key will be defined.
+ . Search - point at a zone or spot to define
+ area then uses the specified tolerance to pick an
+ edge. A fill will be performed in that area.
+ . Point - the point is the Mask, not the color.
+ . (This method has drag capabilities).
+ . Search all - works same as standard Chroma key.
+ Draw mode options let you use
+ . Alpha - matching pixels replaced with see-thru.
+ . Edge to just outline the edges of the region.
+ . Mask - matching color pixels replaced by black.