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# $Id: namespaces.pod,v 1.1 2004/02/26 11:46:20 nik Exp $

=head1 NAME

AxKit::App::Gallery::namespaces - XML namespaces used by AxKit::App::Gallery

=head1 DESCRIPTION

The RDF files generated by AxKit::App::Gallery use elements from a number of
different XML namespaces.  They are described in this document.

=head2 RDF, http://www.w3.org/1999/02/22-rdf-syntax-ns#

The Resource Description Framework is used to provide structure to the meta
information, but says nothing about the actual information.

=head2 FOAF, http://xmlns.com/foaf/0.1/

The Friend Of A Friend vocabulary is used for meta data about people and
things depicted in images in your galleries.  AxKit::App::Gallery writes
the following FOAF elements.

=over 4

=item foaf:thumbnail

Used as the wrapper element for references to the thumbnails that
AxKit::App::Gallery generates.

=back

The default stylesheets support the following elements.

=over 4

=item foaf:depicts

Used to link pictures about a person or object to additional pages of
information about that person or object.

=back

=head2 Dublin Core, http://dublincore.org/documents/dces/

From its web page:

    The Dublin Core metadata element set is a standard for cross-domain 
    information resource description. Here an information resource is 
    defined to be "anything that has identity". This is the definition 
    used in Internet RFC 2396, "Uniform Resource Identifiers (URI): 
    Generic Syntax", by Tim Berners-Lee et al. There are no fundamental 
    restrictions to the types of resources to which Dublin Core metadata 
    can be assigned.

AxKit::App::Gallery writes the following DC elements:

=over 4

=item dc:title

A thumbnail's filename

=back

The default stylesheets support the following elements.

=over 4

=item dc:creator

Will be displayed as the name of the person responsible for taking the
photograph.

=item dc:subject

Will be treated as a comma separated list of keywords relating to the
photograph.

=item dc:description

Will be displayed as a caption for the photograph (in preference to displaying
the photograph's filename).

=back
    
=head2 EXIF, http://impressive.net/people/gerald/2001/exif#

At the time of writing there is no widely agreed upon standard for
representing digital image EXIF data in XML.  Gerald Oskoboiny has a suggested
EXIF namespace, and AxKit::App::Gallery uses this namespace rather then
invent a different one.

=head2 AAG, http://search.cpan.org/~nikc/AxKit-App-Gallery/xml#

This is a catch-all namespace for any information that needed to be
represented in the RDF for which a suitable representation in some other
namespace could not be found.  I plan to remove all references to this
namespace as I become more familiar with available XML vocabularies that can
be used for AxKit::App::Gallery.