The Application of DRCS Within the North American Broadcast Teletext Specification

The North American Broadcast Teletext Specification makes uses of the AT&T Presentation Level Protocol (PLP) for the coding of text and graphic information. It has been suggested that one method for achieving relatively high resolution graphics without burdening user terminal cost is through DRCS. While this is a valid method technically, it presents many problems which relate to access time, transmission efficiency, terminal design and display quality. This paper will detail some of the problems in implementing DRCS as an alternate method for the coding and display of higher resolution graphics within the framework of PLP.