What is keying? Is News Network a live broadcast?

Keying is matting, which is the general name of image or video processing methods.

People, animals, moving animals, etc. And the background are not shot at one time, but the former is selected by the software and put into the ideal background. Now many inferior TV series are like this, and even the scenes of the dialogue between the two protagonists are later.

News broadcast is usually live. As the name implies, live broadcast is recorded and broadcast directly, with no pause. Therefore, the announcer is very demanding, and can't be wrong or stuck. This is also an aspect that news broadcast announcers can best reflect their professional ability.