Chapter 13 • Chroma Key; What Is Chroma Key; Advanced Feature; An Example - Videonics MX-1 Instruction Manual

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Chapter 13 • Chapter 13 •
"Chroma key" is a sophisticated process, normally found only in
high-end professional equipment, that selectively replaces certain
colors of one picture with a second picture.

What is Chroma Key ?

Chroma key allows you to combine two sources so that a defined range of
colors in one picture is stripped away and replaced with the second picture.
The process of selectively replacing part of a picture in this way is called
keying.
The most common example is the weather forecast. A forecaster appears to
be standing in front of a wall-sized map. The forecaster is actually standing in
front of a blue panel and the map is actually a second video source. A chroma
key device "looks" for that specific shade of blue and replaces it with the map
image. Where the original picture was blue, the map appears; where it was
any other color, the original image (the forecaster) appears.

Advanced Feature

Chroma key is an advanced, professional feature that usually requires
some time and care to set up properly. To achieve a good chroma key, you
should plan on some experimentation. The MX-1 includes several features
that allow you to fine-tune the effect, and it is important that you carefully
follow the steps in this chapter for the best results.

An Example

The following is an example of an effect that could be achieved using
chroma key (this is a simulated black and white version of the on-screen
result):
VIDEONICS DIGITAL VIDEO MIXER
Chroma Key