#After effects keylight 1.2 brush skin#
It also happens that blue and green are primary colors not dominant in human skin tones, and most foreground elements (costumes and props), while they might be blue or green, tend to be less purely so. The answer is no, although specialized tools such as Keylight work with only the digital primaries red, green, or blue. Novices often wonder if a background must be blue or green to be keyed. The black areas become transparent, the white areas opaque, and the gray areas gradations of semi-opacity the handling of these gray areas typically determines the success or failure of a matte. The purpose of this article is to help you not only with color keying of bluescreen and greenscreen footage, but with all cases in which pixel values (hue, saturation, and/or brightness) stand in for transparency, allowing compositors to separate foreground from background based on color data.Īll of these methods extract luminance information, which is then applied to the alpha channel of a layer (or layers). The process goes by many names: color keying, bluescreening, greenscreening, pulling a matte, color differencing-even chroma keying, a term that really belongs to analog color television, a medium defined by chroma and heavily populated with weather forecasters. (Several contenders are in some form of development.) As of 2007, the tools to do color keying are more powerful than ever, but the overall process still remains full of pitfalls-which likely won't be overcome until some other means evolves to define precise areas of transparency in foreground footage.
and Adobe Press.Ĭolor keying was first devised in the 1950s as a clever means to combine live-action foreground footage and backgrounds that could come from virtually anywhere. Used with permission of Pearson Education, Inc. This article is adapted from Adobe After Effects CS3 Professional Studio Techniques by Mark Christiansen.