Справочник Пользователя для Tektronix Camcorder 2200

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Background suppression removes traces of the chroma key 
background color from the foreground. The

 button 

turns background suppression on or off. When suppression is 
turned on, the associated control knobs are used to define the 
amount of suppression. 

The 

 

 control adjusts the amount of luminance 

subtracted from the background region of the foreground video.

The 

 

 control adjusts the amount of 

chrominance subtracted from the background region of the 
foreground video. This knob will beep when the chroma has been 
suppressed to zero (at a linear chroma key location).

The 

 knob in the keyers subpanel also will indicate when the 

chroma key has reached a linear level. In terms of the chroma key 
this indicates that the foreground part of the scene is just opaque. 
Only readjust this setting when parts of the foreground are 
transparent where they are picking up background color. 

The 

 button causes the switcher to automatically set up 

the chroma keyer. To do this press the 

 button. This 

causes the chroma keyer to take over the wipe positioner knob 
and puts a cross hair on the chroma key layer of the output. Use 
the positioner to place the cross hair on the background you wish 
to key on and press the 

 key again.