[foms] Proposal: adaptive streaming using open codecs

Steve Lhomme slhomme at matroska.org
Mon Nov 15 10:50:15 PST 2010


On Mon, Nov 15, 2010 at 7:29 PM, Mark Watson <watsonm at netflix.com> wrote:
> Steve,
>
> It depends what kind of sync issues you mean. Actually rendering audio and video out of sync can only happen if you are not paying correct attention to the sample timestamps. This is always a bug (IMO) and independent of the way the media was received.

Yes, the sync has to happen at the renderer level. And yes, audio is
more likely to arrive before a big part of the video. But the time
spent on reading that audio played a lot later, is bitrate taken from
the video stream that we're already waiting for. So on the player
side, it would be better to sync the downloads as well. Any queue with
a max size should be fine. But that's extra code and possibly extra
bugs. Buffering should be kept to a minimum on mobile phones and such.
The good thing is that for adaptative streaming you need to know the
bitrate of the streams you download. So you can have a rough
estimation of how much buffering you need.


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