Called SkyMap, the system relies on an additional datastream sent from the helicopter with the live video. The data includes the current GPS position of the helicopter, the direction in which the camera is facing, and it's zoom level.

The data coming from the helicopter is processed by computer mapping software, which then generates a virtual map giving the same view as the real camera. The mapping software is already programmed to place labels over landmarks on the map, just as Google Earth does over its images.

NHK takes the label layer from the map image and overlays that on the live video image. (A video showing the system in-use and other new broadcasting technologies from NHK .)

If the system is precise enough, they should match up.

In a demonstration of the system at the broadcaster's headquarters on Monday, the system worked well. The demo fed recorded images to the system, but the mapping overlay was being done live in real time over the images.