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Re: Use Cases and Requirements Wiki page updated

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Thu, 12 Mar 2009 09:37:52 +1100
Message-ID: <2c0e02830903111537l214563d6o8906b029a44ceaa8@mail.gmail.com>
To: Guillaume Olivrin <golivrin@meraka.org.za>
Cc: Media Fragment <public-media-fragment@w3.org>
BTW: I have to clarify the use of the word "secondary resource" in the
use cases and requirements. I have noticed that you have removed all
of my uses of this word, since your understanding of a "secondary
resource" is that it is a new resource independent of the original
one. You should actually read up on rfc 3986, section 3.5 -
http://www.ietf.org/rfc/rfc3986.txt . Fragments by definition allow
addressing of a "secondary resource". The "secondary resource" simply
means that there is a resource available as a fragment of the original
resource - it does not mean creating a new resource.

I will revert some of the changes you made, since they now directly
contradict rfc 3986, but I will try not to use the words "secondary
resource", even if that would be the correct technical term to use wrt
rfc 3986 - it just seems to confuse people.


On Thu, Mar 12, 2009 at 9:27 AM, Silvia Pfeiffer
<silviapfeiffer1@gmail.com> wrote:
> Hi Guillaume,
> thanks for clarifying - I will include further changes to the WD to
> make it clear.
> I am not going to bother with the wiki any longer - I don't think we
> need to keep the two in sync and the wiki is just a snapshot of where
> our thinking was about a month ago.
> Also, I think our thinking has changed slightly in recent weeks. We
> have started considering not just to use the fragment specification to
> get a subpart of the original resource, but also to use the query
> specification to get a converted resource. I will have to include this
> thinking into the use cases and specify for the immediate out-of-scope
> cases whether they could be realised with a query syntax and that that
> may be work for the future.
> Thanks for the quick reply!
> Cheers,
> Silvia.
> On Thu, Mar 12, 2009 at 2:46 AM, Guillaume Olivrin
> <golivrin@meraka.org.za> wrote:
>> Hello Silvia,
>>> Use Case 2.4 (really: 3) Spatial Video Pagination - Guillaume, can you
>>> explain how that is spatial pagination? I don't quite understand what
>>> Elaine is actually doing with the video.
>> Ok, let me try again:
>> The idea of "spatial pagination" is to cut a video image into areas,
>> then play each area as a full video, one after another.
>> For example, Elaine has a video mozaic which shows 4 channels. In her
>> original video, all 4 channels are synchronised and playing at the same
>> time, each occupy a quarter of the screen. Now Elaine wants to see all 4
>> channels "full screen", one channel at a time.
>> With the help of Media Fragments she selects in her original video each
>> one of the 4 video regions separately, and then queues each new video
>> fragments into a playlist. Now she can watch each video region
>> separately and sequentially.
>>> Use Case 4.5 Search Engine - I don't understand how that fits within
>>> the section. The section is about annotating, but this one essentially
>>> just re-describes what was already described in Use Case 1.1 Search
>>> Engine. Can you explain where you see the annotations coming in?
>> I guess it's the same as UC 1.1 and we can remove UC 4.5.
>> I can't really justify why it would make a different use case.
>> A typical Web search engines will return a Media Fragment URI if this
>> URI has been used in context of the Keyword e.g. In Web context : <a
>> href="mymediafragment.ogv">This is a nice Bike</a>
>> UC 4.5 is just a case of RDF or MPEG7 annotation schema, which Search
>> Engines will learn to retrieve URI from eventually just like they do
>> from HTML.
>>> I wonder if Use Cases 5.3 and 5.4 are out of scope.
>> These two UCs, it is true, are not really covered in the 'Model of a
>> Video Resource' diagram as it is now.
>> It is not a case of Time, nor Space, nor Track selection but rather a
>> case of Frame selection.
>> Another hybrid case, that of animated GIFs : we can use time= so select
>> a specific "time portion" of a GIF. But do we want to be able to select
>> a specific image/frame out of GIF? The semantics are different.
>> Would it be technically difficult to cover these cases ?
>> These UCs do have very practical applications in mind, but they may fall
>> more under initiatives such as the WebCGM ...
>> As it is, we haven't worked on addressing these cases in the syntax
>> either. So maybe we should mark them 'out of scope' a posteriori. This
>> could be work for a later stage and another release of Media Fragments.
>> Thank you Silvia for including all the UCs in the draft.
>> Should we now reflect these changes you've suggested in both Wiki and
>> Draft?
>> Regards,
>> Guillaume
Received on Wednesday, 11 March 2009 22:38:28 UTC

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