Concepts for the Harmonization of Visual Services in Telecommunication Networks

Abstract

The worldwide telecommunication network for telephone and telex service can additionally be used for other mostly visual — telecommunication services. In the case o£ those visual services the possible varieties of coding and display are very large — thus in the past a number of proposals for different visual services have been made — some of them are introduced on a national basis. Each of the proposed visual services — such as facsimile, Videotext or teletext — found extended interest, without raising the question, whether or not one can be combined with the other — the problem of compatibility is not yet solved on a simple and economic basis.