Segmentation with invisible keying signal

Chroma keying is the process of segmenting objects from images and video using color cues. A blue (or green) screen placed behind an object during recording is used in special effects and in virtual studios. The blue color is later replaced by a different background. A new method for automatic keying using invisible signal is presented. The advantages of the new approach over conventional chroma keying include: (i) Unlimited color range for foreground objects. (ii) No foreground contamination by background color. (iii) Better performance in non uniform illumination. (iv) Features for generating refraction and reflection of dynamic objects. The method can be used in real-time and no user assistance is required. New design of Catadioptric camera and a single chip sensor for keying is also presented.