W3C home > Mailing lists > Public > whatwg@whatwg.org > November 2010

[whatwg] TimedTracks and MPEG transport streams - tracks can change dynamically

From: Eric Winkelman <E.Winkelman@cablelabs.com>
Date: Wed, 24 Nov 2010 09:11:02 -0700
Message-ID: <3C0068AB22D70B4DA32B9A2A965968C76EA1A348BE@srvxchg>
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.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.whatwg.org/pipermail/whatwg-whatwg.org/attachments/20101124/66e82925/attachment.htm>
Received on Wednesday, 24 November 2010 08:11:02 UTC

This archive was generated by hypermail 2.4.0 : Wednesday, 22 January 2020 16:59:28 UTC