"chroma-key"的定义和意义

What is "chroma-key"?

Chroma-key is a visual effects technique used to replace a specific color in a video with another image or background. This is commonly known as "green screen" or "blue screen" technology. In chroma-keying, the background color, usually green or blue, is digitally removed and replaced with different footage or graphics. This technique allows filmmakers to insert actors or objects into various virtual environments or create special effects that would be difficult or impossible to achieve in a physical setting.