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Photo Use Case - relevant Metadata Standards

From: Susanne Boll <susanne.boll@informatik.uni-oldenburg.de>
Date: Thu, 1 Mar 2007 10:59:13 +0100
Message-Id: <3F76079C-3063-418C-9A7D-A2D2939E73D8@informatik.uni-oldenburg.de>
To: MMSem-XG Public List <public-xg-mmsem@w3.org>


For my action point

  ACTION: Susanne to look again in the various systems and standards and
identify 3-4 standards that together could be the solution [recorded in
http://www.w3.org/2006/12/08-mmsem-minutes.html#action06]

I have done a few investigations with regards to photo metadata
standards which I will also add to te use case description.


EXIF is a standard that comprises many photographic and
capture relevant metadata. Even though the end user might
use only a few of the key.value pairs they are relevant at
least for photo editing and archiving tools which read this
kind of metadata and visualize it. So EXIF is a necessary
set of metadata which is needed for photos.

MPEG-7 is far to big even though the standard comprises
metadata elements that are relevant also for a Web wide
usage of media content. The advantage of MPEG-7 is that
one can define an own description scheme and with it
collect a subset of relevant feature related metadata with
a photo.

Tags from Flickr and other photo web sites and tools
are metadata of low structure but high relevance for
the user and the use of the photos. Manually added
they reflect the users knowledge and understanding
of the content which can not be replaced by any
automatic semantic extraction. Therefore a representation
of these is needed. Depending on the source of tags
is might be of interest to relate the tags to their origin
such as "taken from an existing vocablary", "from a
suggested set of other tags" or just "free tags".

XMP seems to be a very promisin standard as it
allows to define RDF-based metadata for photos.
However, in the description of the standard it clearly
states that it leaves the applicaton dependent
schema /vocabulary definition to the application
and only makes suggestions for s set of "gteneric"
sets such as EXIF, Dublinc Core. So the standard
could be a good "host" for a defined photo metadata
description scheme in RDF but does not define it.

PhotoRDF approaches the annotation problem by
defining a (sub)set of standards that together might be
helpful, However, the

RDF - the basis of XMP metadata descripütions, however,
might not in all cases be te optimal standard for
metadata representation. For example, the standard
does not allow to define selectors on top of resources.
However, for a recognized face the metadata might
light to describe the bounding box in the photo where
there was a face detected and the label for this face.
Received on Thursday, 1 March 2007 09:59:42 GMT

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