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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, 
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 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 UTC

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