Abstract
It is often said that a picture is worth a thousand words – a phrase that perhaps hints at some of the problems of describing images in a way that facilitates their retrieval and use. This is additionally complicated by the extreme diversity of images as a category – which includes, artworks, engineering diagrams, maps and charts, the results of biomedical imaging, multimedia, and much more - and also the technical kinds of metadata required to describe them. This presentation will investigate some of the more generic concepts that underpin image description and will outline various approaches to interoperability between image collections. Interoperability will be considered from three main perspectives: collection-level description, the role of metadata in unifying access to diverse image collections and the physical exchange of images (and metadata) between repositories. The presentation will draw upon a range of examples, e.g. from UK initiatives like SCRAN and the FILTER project and will briefly introduce standards like the Dublin Core Metadata Element Set (DCMES) and the Metadata Encoding and Transmission Standard (METS). A final section will reflect on what interoperability might mean for both institutions and users.

Michael Day is a Research Officer at UKOLN, based at the University of Bath (United Kingdom). Since joining UKOLN in 1996, he has worked on a range of metadata-related research projects, which have mostly concerned the development of Internet subject gateways, interoperability, and digital preservation. His most recent projects include ePrints UK – which is concerned with the development of services that will give access to the content of institutional repositories - and a feasibility study of web-archiving.