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Re: Should we consider the user?

From: RaphaŽl Troncy <Raphael.Troncy@cwi.nl>
Date: Fri, 03 Apr 2009 20:15:40 +0200
Message-ID: <49D6524C.3080703@cwi.nl>
To: Jack Jansen <Jack.Jansen@cwi.nl>
CC: Media Fragment <public-media-fragment@w3.org>
Dear Jack,

> Agreed. We could add some non-normative text that implementations are 
> expected to do something like find a random-access-point or I-frame or 
> whatever the underlying format supports. We could also state that if the 
> underlying format allows logical in- and out-points (like Ogg seems to 
> do) these should be used to refine the interval.

I would second Silvia's suggestion: create a new wiki page about 
implementation hints that gather all these thoughts.
An informal action for you?

> Let me give an example. I download 
> <http://www.example.com/example.mp4#t=100,200> to a local file 
> "myclip.mp4". Next, I mail off myclip.mp4 to you. You open it in a video 
> editor. Assuming this video editor will show timestamps as they appear 
> in the original media (as opposed to starting at "0" for every file), 
> there are 3 possibilities:
> a. We standardise that you will always see 100 as the timestamp of the 
> first frame (or a number slightly lower, because of (1) above).
> b. We standardise that you will always see 0.
> c. We specifically state that this is up to the implementation.

Hum, I have to admit that my first original reaction would be: "as soon 
as the client has downloaded the fragment bits and saved them in a new 
file 'myclip.mp4', he has created a *new* resource". Consequently, your 
solution b) that you have just added for the sake of completeness would 
be my favorite :-(
Having said that, and after giving a second thought, I think c) is also 
a good answer, which is also Silvia's favorite. Definitively not a) that 
makes no sense for me.
The rest of the WG, more thoughts?
Best regards.


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 Friday, 3 April 2009 22:38:03 UTC

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