蓝屏幕技术（Blue Screen）是提取通道最主要的手段。它是在拍摄人物或其他前景内容，然后利用色度的区别，把单色背景去掉。所以蓝屏幕技术有个学名叫色度键（Chroma Keying）-Blue screen technology (Blue Screen) is a means of extracting the main channel. It is the prospect of shooting people or other content, and then use the dif