Bluescreen Matting and Chroma Key

The bluescreen matting tech. is invented for the requirements of real-time matting, which is wide used in making movie and TV broadcast. The chroma key means separate the foreground subject with background by their difference in hue(chroma) channel. The photographer take the photo with a specified background with constant color, normally, it is blue or green, so the computer can know where is background and where is foreground, then separate them in realtime, automatically.

This technology can do matting work well, include processing semitransparent area and caculate original foreground color.But, it has two limits:

• The background color can not exist in foreground. Otherwise, the area with same color will be treated as background and turns to be transparent or semitransparent.It is important to choose a right background color depend on foreground subjects.
• For example, if the subject is a person, the skin color is between red and yellow, so we can not use red, orange and yellow as background. Normally, for portrait, we use blue or green.
  It is very sensitive, a pure and constant background is needed. The changes on background color, include shadows and highlights could be captured into output.

For the limits, the bluescreen matting tech is used in professional region only. In this program, the improved bluescreen matting is more flexible for normal photographers:

1,Touch up tools: A set of tools are provided to refine the mattes . The requirements for background is not such strict.

2,Settings for sensitivity: Set right parameters to avoid effect of shadow and highlight in background.