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Idiomas disponibles
Idiomas disponibles
Operating your ATEM Switcher
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Keying on ATEM Switchers
Keyers are a powerful production tool that allow the arrangement of visual elements from different sources
on the same video image.
To do this, multiple layers of video or graphics are stacked on top of the background video. Altering the
transparency of various parts of these layers allows the background layer to be visible. This process is called
keying. Various techniques are used to create this selective transparency and these correspond to the
different types of keyers available on your switcher.
The following section explains luma and linear keyers, which are available either upstream or downstream,
and chroma, pattern and DVE keys, which are upstream keyers.
Understanding Keying
A key requires two video sources; the fill signal and the key or cut signal. The fill signal contains a video
image which is to be stacked on top of the background, while the key signal is used to select regions of the
fill signal to be made transparent. The fill and key signals can be selected from any of the switcher's external
inputs or internal sources, allowing both still and moving images to be used as fill or key sources.
Fill and key signals are selected on the software control panel from drop down lists in the upstream and
downstream key palettes. On the broadcast panel, fill and key signals are selected using the select bus.
There are two types of keyers used in the switcher; upstream keyers and downstream keyers. Four upstream
keyers, also known as effects keyers, are available in the switcher's M/E block. Each upstream keyer can be
set up as a luma, linear, pre-multiplied, chroma, pattern or DVE key. Two downstream keyers are available in
the dedicated DSK block. Each downstream keyer can be set up as a luma or linear key.
The ATEM Production Studio 4K models let you output your key mask via powerful 6G-SDI auxiliary outputs.
It's as simple as pressing the KEY MASK button on the front panel. You can also access your media player
1 and 2 image and key sources by pressing their associated buttons on the front panel. With the key mask
feature you can record your key mask, or alpha channel, in SD, HD or Ultra HD 4K quality via the auxiliary
output. You can also record your green screen video via the program output at the same time. Recording
both sources is useful if you require detailed chroma key post production effects.
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