Digital Broadcasting Systems for Television@ Sound and Data Services; Specification for Conveying ITU-R System B Teletext in Digital Video Broadcasting (DVB) Bitstreams
This ETS specifies the method by which ITU-R System B Teletext [31@ also known as EBU Teletext [4]@m ay be carried in DVB bitstreams. This transport mechanism is intended to satisfy the following requirements: - to support the transcoding of the teletext data into the Vertical Blanking Interval (VBI) of analogue video. The transcoded signal should be compatible with existing TV receivers with teletext decoders; - the maximum data rate for each teletext service is equivalent to 16 lines per field so that the service is always suitable for transcoding into the VBI; - the transmission mechanism should be capable of transmitting subtitles with accurate timing with respect to the video (?.e. to within or near frame accuracy). A more general data transport mechanism for conveying new types of data services is outside the scope of this ETS@ but the transport syntax specified here can also be adapted for other data.