The virtual studio technique is making a revolutionary change in TV studio production. It combines the images of the real actors taken by the real cameras in the TV studio and the rendered images of the virtual background in real time. This allows the actors act freely in the 3D virtual surroundings. The action of the actors is performed in an empty stage with a blue screen as a background. The normal TV studio camera takes the images of the actor action in real time. The images are then combined with the synthesized background in a realistic way in real time with TV broadcasting quality. The technique brings unlimited possibilities of background design in a very economic way which makes a revolution in TV program production.