Metadata Harvesting

The metadata for the Picture Australia service is harvested from participating agencies' web sites using the Open Archives Initiative (OAI) protocol for metadata harvesting for the larger sites or simple web crawl harvesting for the smaller sites. Using OAI has the advantage that only new and changed records need to be harvested, while for web crawl harvesting all records have to be re-harvested each time a harvest is run. The metadata conforms to the Dublin Core or 'DC' metadata format.

Metadata Schema

The harvested metadata is stored at the National Library in XML format, one metadata record per file, loaded into the TeraText database and indexed for searching and browsing. The Picture Australia metadata stored at the National Library conforms to an XML Schema which is available at: http://www.pictureaustralia.org/schemas/pa/picture.xsd. The schema is based on and references the simple DC XML Schema, version 2002-12-12, which is documented at: http://dublincore.org/schemas/xmls/

An example record from the State Library of Victoria in this XML format is available.

Search engine access

Picture Australia metadata is available for indexing by Internet search engines via a set of URL lists. The National Library aims to increase access to both its own digital collections and the collections of cultural agencies participating in collaborative services like Picture Australia through exposure of metadata to Internet search engines.