- From: Susanne Boll <susanne.boll@informatik.uni-oldenburg.de>
- Date: Thu, 1 Mar 2007 10:59:13 +0100
- 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 UTC