Chapter 4 Keys; Overview; Key Types - Sony XVS-9000 User Manual

Keys

Overview

A key is an effect in which a part of the background image
is replaced by an image or superimposed text. The signal
determining how the background is cut out is termed the
"key source," and the signal that replaces the cut-out part
is termed the "key fill." The system component
responsible for processing a key is referred to as a "keyer."
Each M/E bank and the PGM/PST bank has eight keyers.
Keys supported in 4K format
The following keys can be used on each switcher bank.
• 3840×2160P: Key 1 to key 4
• 3840×2160PsF: Key 1 to key 2
Key 3 and key 4 in 3840×2160P format are called "sub
keys" due to restrictions in their functionality. You can
also disable use of key 4.
For details about function restrictions of sub keys, see
"Sub key restrictions" (page 512).
For details about sub key settings, see "Setting the Sub
Key Mode" (page 433).

Key Types

The key type indicates the manner in which the key source
signal is used to cut out the background.
Type Description
Luminance The background is cut out
key according to the luminance (Y)
of the key source signal, and at
the same time the key fill signal
is cut out and then added to
the background signal.
Linear key This is a type of luminance key,
but there is a reduced
variability in gain, allowing
more precise adjustment.
Type
Color vector
key
Chroma key
Wipe pattern
key
Key wipe
pattern key
Clean mode
In a luminance key, linear key or color vector key, you can
enable clean mode. When clean mode is enabled, key fill
is added to the background without cutting out with key
source. This improves the keyed image quality, but means
that the part of the key fill signal which is not to be inserted
must be completely black, or it will color the background.
You set clean mode in the Type menu for each keyer.
Clean
mode
For details, see "Setting the Key Type" (page 109).
Supported
In the following situations, clean mode cannot be enabled.
• When key invert is enabled
• When the key fill is a matte
• When the key edge is an outline
• When the key edge is normal and soft edge is enabled
Supported
• When fine key is enabled
• When key positioning is enabled
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4
Chapter
Description
The key signal is created from
a combination of the
luminance and chrominance
components of the key source
signal. When perfect keying is
not possible with a luminance
key, this allows a key signal to
be created even if the
luminance level is low,
provided that the colors have
high saturation.
A key signal based on a
particular color is used to cut
out the background, and the
key fill is then inserted.
This uses the wipe pattern
selected for a transition to cut
out the background, and the
key fill is then inserted.
This uses the wipe pattern
selected for an independent
key transition to cut out the
background, and the key fill is
then inserted.
Clean
mode
Supported
Not
supported
Not
supported
Not
supported