Photo videotex-a proposal for picture communication in South Africa

An overview of the development of videotex is given, starting from the first Prestel system to the latest developments in videotex, namely photo videotex with CAPTAIN (character and pattern telephone access information network, developed by NTT in Japan) and picture Prestel (developed by British Telecom) as examples. It is noted that three upwards compatible videotex standards are supported by Beltel (the South African videotex system). It is proposed that image coding be used to provide an inexpensive and fast response photo videotex service in South Africa, compatible with Beltel. The different image coding solutions are discussed and reference is made to their advantages and disadvantages. The role that the integrated services digital network (ISDN) will play in this development is also outlined. The applications made available by this service are highlighted