For most television viewers, the hard studio work that goes into getting the right shot and integrating computer graphics into TV shows often goes unnoticed. The studio crew of the future can also disregard these laborious tasks if technology being developed by Japanese public broadcaster NHK (Nippon Hoso Kyokai) to make production easier and more efficient makes it into use.
To produce interesting shots for a show, each video camera is required to shoot at a different angle. This can pose a challenge, as it is quite difficult to make sure that each cameraman is always taking different shots from the others.
In NHK’s prototype studio, the standard shots required are fed into a computer, which then monitors the output from all cameras. One of the cameras is operated manually and supplemented with two robotically controlled cameras. When the cameraman changes the shot on the manually controlled camera, the robot cameras automatically adjust to ensure they are offering contrasting shots of the studio. Thus the computer takes the place of human operators on these two cameras.
Another area that NHK focused on improving is image compositing.
In TV shows, live images are often superimposed on a computer-generated background. This calls for a specially colored set — usually called a “blue screen” because the panels onto which the CG images are projected are blue. A video processor switches the blue parts of the live image for the computer-generated image, but the technique brings some limitations. For example, presenters are often restricted from wearing blue, as it may result in “color bleeding” — and correct lighting is essential to achieve good composition.
On NHK’s demo set, the usual blue panels were gone and the video processor worked on information fed from an infrared image of the studio.
This image came from one of the same studio cameras already being used. The camera had a ring of infrared LEDs (light emitting diodes) around the lens and an additional infrared camera attached to the lens so it could provide the required infrared image along with a conventional image.
The camera beams infrared light on to the set, and reflective panels behind the presenters bounce it back to the camera and on to the video system, where the computer-generated background can be accurately composited with the live video image.
“It is more accurate than chroma-keying, as the HD video cameras integrate the live video with the infrared data in a manner that is high-precision, real-time,” said Hidehiko Okubo, from the Human and Information Science Department of NHK.
The integration is also more accurate. In the demo, the CG image stayed put regardless of whether the cameraman zoomed in or out, up or down.
The “intelligent” studio was shown as part of the annual open day at NHK’s Science and Technical Research Laboratories (STRL) in west Tokyo. NHK plans on improving the studio production technology further by creating a system that focuses on solving problems during the creation stage rather than leaving such work to post-production.
