What’s behind the CCTV weather forecast announcer?

Many viewers don’t know that the background of “Weather Forecast” is just a blue wall. Because of the use of "keying" technology, the map seen on TV appears. "Keying out" simply means that the back of the host is blue. After keying out, all the blue in the picture will become transparent, and then the color-keyed image will be superimposed on the map, so that what you see is the host standing on the map. Map front. Therefore, the weather host is actually "pointing out the country" in front of a blue wall. In front of an empty blue screen, the host must not only express accurately, but also accurately point out the information described in the manuscript on the graph based on the changes in the graph. location. "Anyone who has visited the studio of the "Weather Forecast" program will find that it is really difficult and even a bit frustrating to quickly and accurately point out the geographical location in front of a blue wall."

Reference materials: /v/m/2009-09-16/03042700619.shtml