Sony DVS-7300, User Manual

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Chapter 5 Chroma Keying
Making the window adjustment
You can adjust the detection range of the information used to produce the key
signal. When this function is off, the default range is used for image
adjustment.
Chroma keying uses a particular hue (typically a blue background color) in
the foreground signal to produce the key signal, and the window function
specifies the range of signal values to be regarded as this background hue.
On the DVS-7000, the range for this background hue corresponds to a
truncated sector as seen on a vectorscope (see illustration below). This range
is specified by two parameters: the “ANGLE” parameter, which determines
the range of the hue parameter, and the “CROP” parameter, which determines
the degree of truncation.
Window adjustment
• The default values (and the values when the window function is off) are:
CROP 37.5 and ANGLE 93.7.
• The values for CROP and ANGLE are not affected by the auto chroma key
function.
Before adjusting the window parameters, it is essential to have adjusted the
clip, gain and hue parameters correctly. After doing this, use the following
procedure.
Basic Chroma Key Operations
Key signal values (to be replaced
by background signal)
Basic hue
specified by
HUE setting
Values remaining as
foreground
ANGLE
CROP