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Re: Is there proposal of accessing metadata of media files?

From: Dan Brickley <danbri@danbri.org>
Date: Tue, 13 Oct 2009 21:46:56 +0200
Message-ID: <eb19f3360910131246p674a4696h420a54d2093995db@mail.gmail.com>
To: Felix Sasaki <felix.sasaki@fh-potsdam.de>
Cc: "Tran, Dzung D" <dzung.d.tran@intel.com>, Robin Berjon <robin@berjon.com>, Arthur Barstow <art.barstow@nokia.com>, Soohong Daniel Park <soohong.park@samsung.com>, ext Shumpei Shiraishi <shumpei.shiraishi@gmail.com>, public-webapps WG <public-webapps@w3.org>, "public-media-annotation@w3.org" <public-media-annotation@w3.org>, "public-device-apis@w3.org" <public-device-apis@w3.org>
On Tue, Oct 13, 2009 at 9:16 PM, Felix Sasaki
<felix.sasaki@fh-potsdam.de> wrote:
> Hello Dzung,
> sorry for jumping in, but from
> http://dev.w3.org/cvsweb/~checkout~/2009/dap/api-reqs/Overview-FPWGN.html?rev=1.6&content-type=text/html;%20charset=utf-8#gallery
> "Exposing metadata is tricky, often giving a choice between creating an
> endless ontology or building an open-ended system that guarantees no
> interoperability. "

I liked that observation.

Basically it says that you can take the path of hardcoding something
quite fixed, eg.


...and have a rigid, predictable system but hard to manage since
everyone's requirements need to be addressed by the API itself... or
you can have an API that is much more neutral, and the fields
requested are passed in as arguments (perhaps even a full query

In the latter case, the basic API isn't enough to guarantee interop;
the basic schema or query structures needs to be agreed and documented

> I am not sure what you are looking for:
> - an ontology defining mappings between existing metadata (being defined by
> media annotations working group (MAWG))
> - new metadata properties defined as an ontology (not defined by MAWG)
> - an API which reflects the mapping of existing properties in the ontology
> to access methods for metadata (provided by MAWG)
> - an API for low-level reading mechanisms (not provided by MAWG - e.g. for
> XML-based formats provided by an XML-parser)

Another candidate perhaps: a set of standard queries (expressed in
SPARQL) that can match against some/all of this metadata, and whose
API is an SQL-esque tabular resultset.



ps. for some very old (SVGOpen 2004) notes on this see

Received on Tuesday, 13 October 2009 19:47:31 UTC

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