W3C home > Mailing lists > Public > public-media-fragment@w3.org > October 2010

Re: Media Fragments in Opera

From: Philip Jägenstedt <philipj@opera.com>
Date: Wed, 20 Oct 2010 11:09:41 +0200
To: public-media-fragment@w3.org
Message-ID: <op.vkvaec05sr6mfa@kirk>
On Mon, 18 Oct 2010 12:25:27 +0200, Silvia Pfeiffer  
<silviapfeiffer1@gmail.com> wrote:

> On Mon, Oct 18, 2010 at 7:55 PM, Philip Jägenstedt <philipj@opera.com>  
> wrote:
>> * It's not clear to me what to do with the smpte formats. In our  
>> underlying
>> media framework (GStreamer) time is expressed in nanoseconds, so it  
>> doesn't
>> actually give any great precision that using 9 decimals. For now, I've  
>> not
>> added support for the smpte formats at all. Are there any existing
>> implementations or indications that anyone does want to implement it?
>
> It's mostly there because RTP/RTSP uses it, too, IIRC.

Is this reason enough for it to be part of MF? Are there compatibility  
requirements I'm not aware of?

>> * The use case for 'clock' syntax is pretty clear, but AFAIK the time  
>> in UTC
>> isn't available in Ogg or WebM, so I'm not sure what to do with it.
>
> Ogg Skeleton has the possibility to add a UTC marker and all time
> offsets from there can be added onto the UTC time marker. See
> http://wiki.xiph.org/Ogg_Skeleton_4 and search for UTC. Not that I've
> seen it used yet, but flumotion might need it if/when it's going to do
> timed fragment URIs with UTC time.

OK, thanks! I guess for WebM this won't happen at least until we add  
metadata support.

-- 
Philip Jägenstedt
Core Developer
Opera Software
Received on Wednesday, 20 October 2010 09:10:22 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 20:52:45 UTC