What is the purpose of chroma key technique?

The purpose of the chroma key technique is to create a visual illusion by using color backgrounds. This technique allows filmmakers and video creators to replace a specific color in their footage (often a bright green or blue) with another image or video, effectively enabling the creation of composite images. For instance, a subject filmed in front of a green screen can have any background added in post-production, making it look like they are in a completely different environment.

This technique is widely used in various media, including movies, television broadcasts, and news programs to create engaging and dynamic visuals. Chroma keying enhances creativity and storytelling by providing the capability to place subjects in fantastical settings or create seamless transitions between different scenes without the need for physical location changes.