I'm investigating how TimedTracks can be used for in-band-data-tracks within 
MPEG transport streams (used for cable television).

In this format, the number and types of in-band-data-tracks can change over 
time.  So, for example, when the programming switches from a football game to a 
movie, an alternate language track may appear that wasn't there before.  Later, 
when the programming changes again, that language track may be removed.

It's not clear to me how these changes are exposed by the proposed Media 
Element events.

The "loadedmetadata" event is used to indicate that the TimedTracks are ready, 
but it appears that it is only fired before playback begins.  Is this event 
fired again whenever a new track is discovered?  Is there another event that is 
intended for this situation?

Similarly, is there an event that indicates when a track has been removed?  Or 
is this also handled by the "loadedmetadata" event somehow?

Thanks!

Eric Winkelman
---
e.winkelman  cablelabs.com
Cable Television Laboratories, Inc.

Reply via email to