Chroma Key is a film and television technique
Chroma Key is also known as Bluekey, blue screening, green screening, Greenkey, colour value or color specific and is a technique in which first a subject is filmed against a blue or green background. Then, with colour filters and computer technology, this background can be filtered out by a different background. Many modern films use Chroma key, especially films with many special effects such as science fiction and fantasy films. A well-known example of chroma key is the weather forecast where the weatherman or weather woman stands for a blue background and the weather map with chroma key is filled in.
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