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SECTION 13.1 CHROMAKEYING


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Chromakeying has become an essential tool in video and film production. Typically, foreground footage is shot in front of a blue or green screen, and then that background color – the key color – is treated as transparent, allowing another image to be inserted.


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For example, when you see a television meteorologist in front of a weather map, that person is almost certainly posed in front of a green screen. The background is ‘keyed out’ and replaced by computer generated imagery.


Of course, if you choose poor settings, foreground areas may inadvertently be cut away as


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well. Good keying often requires judicious balance between ‘too much’ and ‘too little’. Let’s consider the tools TriCaster provides to help you achieve a great result.