Chroma Key; Overview; Setting A Chroma Key; Chroma Key Adjustments - Sony XVS-G1 User Manual

Chroma Key

When chroma key is selected as the key type, you can
configure and adjust the chroma key.
This section describes the M/E-1 key 1 menu as an
example.

Overview

A key signal based on a particular color is used to cut out
the background, and a key fill is then inserted to create an
image.
In an image created using a chroma key, the image at the
rear is called the background and the inserted image is
called the foreground.
Two mixing methods, normal mix and additive mix, are
available.
Normal mix
The background which is cut out by a key signal is mixed
with the foreground which is cut out by the key signal.
Additive mix
The background which is cut out by a key signal is mixed
with the unchanged foreground.
This is effective for a natural-looking composite when the
scene includes glass or other translucent objects.
In an additive mix, the blue (background color) parts of the
foreground must be converted to black using the color
cancel function.
For details about color canceling, see "Adjusting color
cancel" (page 77).
Plane function
In an additive mix, since the background is mixed with the
unchanged foreground, an uneven blue background may
appear in the composed image.
You can specify a specific luminance level and remove
parts of the blue background with lower luminance to
avoid this unevenness.
Auto chroma key
You can specify a specific color of the foreground that
automatically generates a chroma key.
Immediately after an auto chroma key is executed, manual
fine tuning is effective, if required.
The following settings can be adjusted manually.
• Key active
• Color cancel
• Window
• Y balance
• Shadow
• Foreground color correction

Setting a Chroma Key

Composing an image by chroma keying
1
Open the Home > M/E-1 > Key1 > Type > Chroma
Adjust menu (11101.12).
2
Execute an auto chroma key.
Adjust the chroma key manually as required.
For details, see "Chroma Key Adjustments"
(page 75).
3
In the [Mix Mode] group, select a chroma key
composition method.
Normal Mix: Normal mix
Additive Mix: Additive mix
Setting the plane function
Note
When the chroma key composition method is a normal
mix, the plane function cannot be set.
1
Open the Home > M/E-1 > Key1 > Type > Chroma
Adjust menu (11101.12).
2
Set the [Plane] button to the on state and set the
following parameter.
No. Parameter
1 Luminance
To disable the plane function, set the [Plane] button to
the off state.

Chroma Key Adjustments

Automatic adjustment using an auto chroma key and
separate manual adjustment of required processing can be
performed.
Auto chroma key
You can specify a specific color (blue background, for
example) of the foreground to automatically generate a
chroma key.
Key active
When the key active function is enabled, the composite
image is output to a monitor, and you can adjust the
composition while viewing the monitor.
75
Adjustment
Luminance