W3C home > Mailing lists > Public > public-media-capture@w3.org > October 2012

RE: synchronization

From: Sunyang (Eric) <eric.sun@huawei.com>
Date: Thu, 18 Oct 2012 02:57:50 +0000
To: Jim Barnett <Jim.Barnett@genesyslab.com>, "public-media-capture@w3.org" <public-media-capture@w3.org>
Message-ID: <9254B5E6361B1648AFC00BA447E6E8C32AECE350@szxeml545-mbx.china.huawei.com>
That is why in "media capture an streams", it is said " Different MediaStreams do not need to be synchronized.", "do not need" means synchronization may happen but not need to happen each time.


From: Jim Barnett [mailto:Jim.Barnett@genesyslab.com]
Sent: Wednesday, October 17, 2012 11:20 PM
To: public-media-capture@w3.org
Subject: synchronization

The spec says that synchronization happens at the MediaStream level, but doesn't explain how it occurs.  It also doesn't explain how clients get media from either MediaStream or Track.  This leaves some edge cases up in the air.  Suppose we have Tracks t1 and t2 inside MediaStream m1 and Tracks t2 and t3 inside MediaStream m2:  will m1's clients and m2's clients see the data from t1 and t3 as synchronized?  t1 and t3 are both synchronized with t2, but in different MediaStreams.  Is synchronization transitive across MediaStreams?

Another way to put it is to ask whether the different MediaStreams can provide different synchronizations.  Can m2 provide data from t2 that is not synchronized with t1?   If synchronization is purely at the MediaStream level, it would seem to me that should be allowed.  On the other hand, if we mean that it is the MediaStream's job to make sure that the Track _objects_ are synchronized, then if t1 is synced with t2 in one MediaStream, it will be synched with it in _any_ MediaStream.  (So synchronization would be transitive across MediaStreams.)

-        Jim
Received on Thursday, 18 October 2012 02:59:18 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 16:26:12 UTC