Method and apparatus for multiplexing separately-authored metadata for insertion into a video data stream

A method for coordinating authored video metadata with video data streams, comprising steps of:

• (a) ensuring the video data streams have presentation time stamps (PTS);
• (b) feeding the video data streams to authoring stations;
• (c) authoring intermittent metadata at the authoring stations to be later used to enhance the video data streams;
• (d) marking the metadata with presentation time stamps (PTS) taken from the video data streams at the time of authoring the metadata;
• and
• (e) multiplexing the authored metadata with the video data streams, wherein the multiplexer places the metadata in relation to video data streams according to the PTS, and multiple sources of video is fed to the multiplexer as well as metadata, and the multiplexer compensates for real-time differences between the multiple sources.

A video multiplexing system comprising:

• inputs for digital video data streams;
• and
• inputs from video authoring stations, comprising intermittent metadata associated with the video data streams by presentation time stamps (PTS) copied from the video data streams at the time of authoring;
• and
• an output to a video transport interface;
• wherein one or more of the inputs for digital video data streams are from stored sources, and the multiplexing system notes the presentation time stamps associated with the authored metadata, monitors real time clocks of the sources and uses the information to compensate one or both of the multiple streams, and places the authored metadata relative to the video data streams for transport to end users.