Virtual studio
The term virtual studio can refer to any number of technological tools which seek to simulate a physical television and/or movie studio. One such use of the term follows.
A virtual studio is a television studio that allows the real-time combination of people or other real objects and computer generated environments and objects in a seamless manner. For that integration we will use chromakey technology. A key point of a virtual studio is that the real camera can move in 3D space, while the image of the virtual camera is being rendered in real-time from the same perspective, therefore, this virtual scene has to adapt at any time to the camera settings (zoom, pan, angle, traveling, etc.). This is what differentiates a virtual studio from the traditional technique of chromakey. It also differs from techniques used in film, in which scenes are edited later. A virtual studio does not need any post production because it is in real-time. However a 3-D graphic artist and 3D computer graphics software are needed to create the virtual background, and any graphics that appear in front.
There exist many technical solutions for creating virtual studios, but most of them include the following components:
- Camera tracking, that uses either optical or mechanical measurements to create a live stream of data describing the exact perspective of the camera.
- Realtime rendering software, that uses the camera tracking data and generates a synthetic image of a television studio.
- A video mixer, which combines the video from the camera with the video from the realtime rendering software to produce a final video output. One of the most common ways to mix the video to replace a chroma key background.
A major difference between a virtual studio and the bluescreen special effects used in movies is that the computer graphics are rendered in realtime, removing the need for any post production work, and allowing it to be used in live television broadcasts.