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Re: ISSUE-2: What is the mime type of a media fragment? What is its relation with its parent resource?

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Wed, 28 Jan 2009 11:37:27 +1100
Message-ID: <2c0e02830901271637r1098fd0fx2207c38070c1543c@mail.gmail.com>
To: Michael Hausenblas <michael.hausenblas@deri.org>
Cc: RaphaŽl Troncy <Raphael.Troncy@cwi.nl>, Yves Lafon <ylafon@w3.org>, Media Fragment <public-media-fragment@w3.org>

Hi Michael,

I actually also don't quite understand what your question is.

Is this a question of process or a technical question?

If it is process:
Sure we need test implementations. It is well described in our
charter: http://www.w3.org/2008/01/media-fragments-wg.html .

If it is technical:
Your example http://www.example.com/movie.mov#xywh=20,20,40,40 is well
described in the requirements,
 e.g.
http://www.w3.org/2008/WebVideo/Fragments/wiki/Use_Cases_%26_Requirements_Draft#Recompositing_Media_Fragments
http://www.w3.org/2008/WebVideo/Fragments/wiki/Use_Cases_%26_Requirements_Draft#Annotating_Media_Fragments
basically everywhere that the word "spatial fragment" is used.

Does that help?

Regards,
Silvia.


On Wed, Jan 28, 2009 at 11:12 AM, Michael Hausenblas
<michael.hausenblas@deri.org> wrote:
>
> Raphael,
>
> I know, impolite, but let's start at the end:
>
>> Does that answer to your question?
>
> No ;)
>
> For some background reading I'd suggest [1].
>
> The problem is that with the pure syntax (as of [2]) we can't fully specify
> any conformance (UA, or whatever).
>
> Example:
>
> In RDFa (where I've been responsible for the TC, now with Manu Sporny
> together), we have a processing model that would generally define how to
> process an XHMTL+RDFa page in order to produce RDF triple. Now, we can't
> define the output for any case (obviously too many combinations possible ;)
> In order to define the semantics we use the TC [3]. I'll use the first TC in
> the suite as an example:
>
> ...<p>This photo was taken by <span class="author" about="photo1.jpg"
> property="dc:creator">Mark Birbeck</span>.</p> ...
>
> in our understanding should produce the triple
>
> <http://www.w3.org/2006/07/SWD/RDFa/testsuite/xhtml1-testcases/photo1.jpg>
> dc:creator "Mark Birbeck" .
>
> Hence a back and forth between syntax and TC in order to define the
> semantics. We reviewed each TC manually and the RDFa TF would then agree,
> yes, this is the expected outcome (in sync with the syntax).
>
> Then, after the TC have been completed the implementers were called (yeah,
> sure they already did that in parallel, but theoretically sufficient if you
> do it later).
>
> In this second phase, the TC were used to determine if and to which degree
> the RDFa syntax spec could be implemented (and, alas, also, if you have two
> implementations that pass all TC you might be able to assume they are
> interoperable). This is an important criteria in the Rec Track [4]:
>
> "The Working Group is NOT REQUIRED to show that a technical report has two
> independent and interoperable implementations as part of a request to the
> Director to announce a Call for Implementations. However, the Working Group
> SHOULD include a report of present and expected implementations as part of
> the request."
>
> Though not required I guess it is common and a good practice and fosters
> adoption.
>
> Now, back to the question: How does the above described map to our work?
>
> Take <http://www.example.com/movie.mov#xywh=20,20,40,40> as an example.
>
> How would the TC look? How do we specify the semantics of it?
>
> Cheers,
>      Michael
>
> [1] http://www.w3.org/QA/WG/2005/01/test-faq
> [2] http://www.w3.org/2008/WebVideo/Fragments/wiki/Syntax
> [3] http://rdfa.digitalbazaar.com/rdfa-test-harness/
> [4] http://www.w3.org/2005/10/Process-20051014/tr.html#cfi
>
> --
> Dr. Michael Hausenblas
> DERI - Digital Enterprise Research Institute
> National University of Ireland, Lower Dangan,
> Galway, Ireland, Europe
> Tel. +353 91 495730
> http://sw-app.org/about.html
>
>
>> From: RaphaŽl Troncy <Raphael.Troncy@cwi.nl>
>> Organization: CWI
>> Date: Wed, 28 Jan 2009 00:35:04 +0100
>> To: Michael Hausenblas <michael.hausenblas@deri.org>
>> Cc: Yves Lafon <ylafon@w3.org>, Media Fragment <public-media-fragment@w3.org>,
>> Silvia Pfeiffer <silviapfeiffer1@gmail.com>
>> Subject: Re: ISSUE-2: What is the mime type of a media fragment? What is its
>> relation with its parent resource?
>>
>> Dear Michael,
>>
>>> I'll restate it and would like to ask you to explain me how we gonna handle
>>> this - in case I understand it I offer a bounty (not sure if that has
>>> already been assigned, so ...), that is, to take care of the Test Cases:
>>
>> [Being not Yves]
>> What is exactly your question? What would be the implementations of the
>> spec and the test cases that come with for the CR exit?
>>
>> What we have discussed so far:
>>    - implementation of a smart UA, that can transform the fragment
>> requested into some new http headers and do either the 2-ways or the
>> 4-ways handshake ... ideally in collaboration with the browser vendors.
>>    - implementation of a server, that can handle media fragment request,
>> slide the media file on demand, and serve it to the client
>>
>> Yves has his own server (jigsaw)
>> Jack though he could do something with Ambulant, the SMIL player.
>> Test cases will ensure that communication between UA and server will
>> follow what is specified in the spec (re: 2-ways / 4-ways handshake in
>> case of http implementation, etc.)
>>
>> Does that answer to your question?
>> Best regards.
>>
>>    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, 28 January 2009 00:38:04 GMT

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