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Video Mix/Effects
M/Es and Keyers
A GV K-Frame XP M/E is a subsystem of a video production switcher that can create a
composite of two or more pictures. An M/E includes multiple source selection buses and
provides transition (mix and wipe) and keying capabilities on the selected signals.
Six Keyer System Example
Keyers are used to insert part of one picture into another to create a composite picture.
Keying involves three signals:
• background,
• key cut, used to specify where to cut a hole in the background, and
• key fill, used to fill the hole in the background. The fill can be an incoming video signal
or it can be an internally generated matte.
A separate key cut input signal is not necessarily required for keying. For example, a self key
(also called a video key) uses the same input signal for both key cut and key fill.
The GV Switcher system supports the following types of keys:
• Linear Key (fixed and adjustable)
• Luminance Key
• Preset Pattern
• Chroma Key (option)