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Advanced keying with After Effects: Part 2 by Chris Zwar - ProVideo Coalition
Regardless of which keying plugin you're using, and no matter how advanced their algorithms are, you can always get better results by pre-processing your footage. The term "pre-processing" refers to any effects / plugins applied to the footage before the keying plugin. In essence, we are using other effects to help the keying plugin get a better result.
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