Tektronix 2200 TV Video Accessories User Manual


 
3-15
Switcher Module Description
The Keyer Mezzanine:
Demultiplexes parallel inputs from Keyer Carrier Module
May use the key source and the key fill video to create a clipped and
gained key and a shaped video fill
Can move the key horizontally in subpixel increments over a six pixel
range
May modify offset and gain on the input video fill
Generates two key fill mattes which can be substituted for the video
Uses signals from the wipe generator to generate a wash between the
two mattes
May mask the key with both force and inhibit masks
Times the inputs
Provides a washed matte border for preset patterns
Input signals for each Keyer Mezzanine Module are:
Video fill source
Video key source
Each of the Key Mezzanine Modules creates:
A shaped video fill or washed matte
A clipped, gained and masked key
The Keyer Mezzanine Module has circuitry to time the video and key
signals. The timing is set so that the signals are aligned at the output of the
Keyer Carrier Module even though the keyer path is longer (because of the
BORDERLINE and key NAM) than the background path.
The Keyer Mezzanine Module uses the box mask from the Keyer Carrier
Module, or the wipe masks from the Mix/Wipe Module, to mask the keys
and key fill. The keys can be filled with matte. The matte is generated by a
dual matte generator on the Key Mezzanine Module. The matte can be
modulated by the wipe signal from the Mix/Wipe Module.
The functions, inputs, outputs, and processor used for each of the Key
Carrier and Keyer Mezzanine combinations is given below.