Method and apparatus for determining data is available using a virtual time base

摘要

The invention provides a method and apparatus that addresses and resolves the issues currently affecting the ability to offer Enhanced TV, in particular, those issues concerning timing and synchronization, interaction with other modules in the STB, and distribution.

主权项

1. A method comprising:
receiving, by a computing device, a data stream comprising a plurality of data substreams, a first data substream of the plurality of data substreams identifying an availability of a first enhancement presentable with one or more video programs; receiving a plurality of virtual time base control data respectively for the plurality of data substreams; determining a first virtual time base for the first data substream based on a first virtual time base control data of the plurality of virtual time base control data; determining whether the first enhancement is available using the first virtual time base; and causing presentation of the first enhancement synchronously with the one or more video programs, wherein the first virtual time base control data comprises an absolute time and a time base.