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Re: Should we consider the user?

From: RaphaŽl Troncy <Raphael.Troncy@cwi.nl>
Date: Wed, 01 Apr 2009 14:50:40 +0200
Message-ID: <49D36320.2080104@cwi.nl>
To: Jack Jansen <Jack.Jansen@cwi.nl>
CC: Media Fragment <public-media-fragment@w3.org>
I like Silvia's answer, 
http://lists.w3.org/Archives/Public/public-media-fragment/2009Apr/0004.html 
:-)
To follow today's discussion:

> there are a number of questions:
> 1. Does this return the exact 1s-2s time fragment? This is probably 
> impossible, the next best thing is the smallest interval that contains 
> this interval, i.e. from the last frame before or at 1s to the first 
> frame at or after 2s.
> 2. Alternatively, we could say the user gets a "reasonable" interval 
> around 1s-2s, so implementations can cut at I frames. This would 
> forestall transcoding. But: now we need to define "reasonable".

I would also favor the best effort approach, i.e. find the closest 
interval that encapsulates the client request.

> 3. What about audio/video sync? If the user gets synced a/v we need to 
> do recoding.

Again, best effort and we need to find out when we have extreme un-sync 
that will not be tolerate by the user.

> 4. What about timestamps in the media? Are these the originals?

I haven't understood this question if it is not linked to the 
in-context/out-context discussion.

> 5. What about spatial crops? Same questions as for (1) and (2)

We leave undefined for now what the spatial cropping actually do :-) We 
will need to write down what are the current state of our thoughts: 
basically, spatial cropping requires transcoding for all the current 
known codecs formats except (perhaps) Motion JPEG2000.

   RaphaŽl

-- 
RaphaŽl Troncy
CWI (Centre for Mathematics and Computer Science),
Science Park 123, 1098 XG Amsterdam, The Netherlands
e-mail: raphael.troncy@cwi.nl & raphael.troncy@gmail.com
Tel: +31 (0)20 - 592 4093
Fax: +31 (0)20 - 592 4312
Web: http://www.cwi.nl/~troncy/
Received on Wednesday, 1 April 2009 12:51:26 GMT

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