Bandwidth efficient communication of user data in digital television data stream

摘要

A method and apparatus are provided for communicating VBI user information for digital television. A syntax is provided which allows the transport of closed captions, non-realtime video, sampled video and AMOL. Non-realtime video can be used to transport various types of data, such as a vertical interval test signal (VITS) through the system at full resolution. The provision in the syntax of a count for each type of VBI user information enables the adjustment of a digital television data stream to accommodate variable amounts and types of such information without space being reserved in advance. The provision of a priority number in the syntax enables decoders to discard VBI user information priorities which are not supported by the particular decoder.