Abstract: The system generates a composite image on a pixel-by-pixel basis by selectively mapping source pixels provided by video sources of different video formats onto destination pixels in the composite image. The mapping is accomplished by encoding the source pixels into digital words, each word having a color information part and a video format identifier, used to decode the color information part upon processing to organize the composite image. Combining video signals with computer-generated graphics data is achieved under control of the graphics data being interpreted either as video format identifier or as color. If the color of the destination pixel is determined by one of the video sources, the graphics data is used to select the appropriate decoding. The system permits a modular architecture and simple merging with a PC.

Abstract: A description is given of a data processing network that is constructed as a product network of two or more factor networks. At least one of the factor networks is a chordal ring of at least five stations, or a generalized chordal ring. A generalized chordal ring is formed by dividing each of the stations in a chordal ring (124, 130, 136) into a number of sub-stations. The sub-stations within a station constitute a homogeneous network. The external connections of a station are divided over the relevant sub-stations. In this way an optimum value for the degree (G) and diameter (D) of the network can be chosen on the basis of a selection strategy.