User manual

Imagestore HDTV User Manual Overview
Miranda Technologies Ltd Page 63
Full keying is where the Fill signal is multiplied by the derived key signal
prior to being added to the modified Background signal.
Source
Self key When the source option is set to self, the key data is derived from
the luminance content (Y value) of the "Fill" signal itself.
Separate key When the source option is set to separate, the key data is
derived from the luminance content (Y value) of the separate "Key" image.
None When the source option is set to none the key for an image is set to
white so that there is no image transparency.
Type
Full Key is where the foreground image is passed only where the key signal
is present.
Linear Key is where the background and foreground are summed and the
foreground is unaffected by the key.
Sense
Normal, a black-level key signal that will cause the "Fill" image to be fully
transparent and not appear over a background. A white-level key signal will
cause the "Fill" image to be opaque with no background appearing through.
Intermediate keying levels will produce a pro-rata transparency effect.
Invert reverses this effect and white-level key signals now create a fully
transparent "Fill" image with black-level signals producing an opaque "Fill"
image.