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Re: ISSUE-3 (mhausenblas): Does our MF URI syntax imlpy that we need to update MIME Type registrations?

From: Raphaël Troncy <Raphael.Troncy@cwi.nl>
Date: Thu, 20 Aug 2009 11:14:31 +0200
Message-ID: <4A8D13F7.8000306@cwi.nl>
To: Media Fragments Working Group WG <public-media-fragment@w3.org>
Dear all,

Following the discussion of the 19/08/2009 telecon [1], and the output 
of the ACTION-89 [2], we can now close this issue raised by Michael. The 
procedure is now clear and a new follow-up ISSUE-13 [3] has been raised. 
This new issue is a reminder that we should write a small Internet draft 
that will link back to the media fragment specification and a template 
describing the how-to register the media fragments for various media types.

   Raphaël

[1] http://www.w3.org/2009/08/19-mediafrag-minutes.html
[2] http://www.w3.org/2008/WebVideo/Fragments/tracker/actions/89
[3] http://www.w3.org/2008/WebVideo/Fragments/tracker/issues/13

> ISSUE-3 (mhausenblas): Does our MF URI syntax imlpy that we need to update MIME Type registrations? 
> 
> http://www.w3.org/2008/WebVideo/Fragments/tracker/issues/3
> 
> Raised by: Michael Hausenblas
> On product: 
> 
> In [1] Michael argued that whenever we talk about URI semantics, we need to start with RFC3986 section 3.5: 
> 
> 'The semantics of a fragment identifier are defined by the set of
> representations that might result from a retrieval action on the primary
> resource. The fragment's format and resolution is therefore dependent on the
> media type [RFC2046] of a potentially retrieved representation, even
> though such a retrieval is only performed if the URI is dereferenced. If
> no such representation exists, then the semantics of the fragment are
> considered unknown and are effectively unconstrained. Fragment identifier
> semantics are independent of the URI scheme and thus cannot be
> redefined by scheme specifications.'
> 
> Further, from RFC2046 we learn that the MIME Type Registrations (taking a JPG still image as an example) for JPEG 2000
> (ISO/IEC15444) is specified in RFC3745 where no fragments are defined,
> hence the general rules from RFC3986 apply.
> 
> Do we need to update all registries of targeted media types or are we fine with sticking to the fallback rule from RFC3986 ('If no such representation exists, then the semantics of the fragment are considered unknown and are effectively unconstrained.' 
> 
> [1] http://lists.w3.org/Archives/Public/public-media-fragment/2009Jan/0043.html

-- 
Raphaël Troncy
EURECOM, Multimedia Communications Department
2229, route des Crêtes, 06560 Sophia Antipolis, France.
e-mail: raphael.troncy@eurecom.fr & raphael.troncy@gmail.com
Tel: +33 (0)4 - 9300 8242
Fax: +33 (0)4 - 9000 8200
Web: http://www.cwi.nl/~troncy/
Received on Thursday, 20 August 2009 09:15:15 GMT

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