Sony 9000 Manuel D’Utilisation

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Keys

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Window adjustment

In normal chroma keying, the key signal is based on the chrominance 
component only, and all elements of the foreground with the same hue are 
replaced by the background. Using the Y balance function, you can specify a 
luminance level range within which the key is active, and replace the specified 
part by the background.
You can use the Y balance function independently on the key signal for the 
composition and the key signal for the color cancel function. When applied to 
the key signal for the composition, this produces the foreground with the color 
cancel effect applied. This can therefore be used to provide an impression of 
smoke, for example.
When the Y balance function is applied to the color cancel key, the relevant 
part is output in its original color without canceling, and therefore it is possible 
to combine colors which are the same color as the background (i.e. typically 
blue) in the foreground.

This function provides a more realistic treatment when the shadow of an object 
in the field of view falls on the blue background. Since parts of the blue 
background darker than a specified intensity are treated as shadows, there is no 
effect on cutting out of the foreground.

You can vary the foreground signal gain, or change the hue. There are separate 
adjustments for the gain of the overall video signal, and Y and C components.

Reference color 
specified by Hue 
setting

Range of colors creating the key signal 
(to be replaced by background signal)

Range of colors remaining 
as foreground

a) The Crop and Angle values do not change even if 

you use the auto chroma key function.

Angle 

a)

Crop 

a)