The Annotation CReatiON for Your Media (ACRONYM) tool is a Semantic Web-based photo annotation tool that can annotate any JPEG image on the Web with RDF. It focusses on the most important recall cues and takes advantage of RDF's powerful expressivity, interoperability and mobility while hiding its complexities from the user. ACRONYM makes use of the EXchangeable Image File (EXIF) format metadata that is created and stored inside JPEG photo files by off-the-shelf digital cameras. This commonly includes a timestamp of when the photo was captured, shutter speed, exposure time etc. but can also include the co-ordinates of the camera at the time of capture if the camera has been coupled with a GPS receiver. ACRONYM also makes frequent use of the GeoNames online geographical database, map, ontology and Web services.

Finding photos is now a major activity for Web users, but they suffer from information overload as their attempts to find the photos they want are frustrated by the enormous and increasing number of photos. The processing speed of computers can be leveraged to perform the hard work of finding photos for the user and to thereby alleviate the information overload. To enable the machine to retrieve photos for the user, we must first examine how users mentally recall photos themselves. Research indicates that users recall photos primarily by cues in the following categories, in descending order of importance: (i) who is in the photo; (ii) where the photo was taken; and (iii) what event the photo covers. Searchable description metadata in these categories can be created for photos and search engines can then match user queries with these descriptions and present the best matches to the user. A key challenge is how to create this useful, searchable description metadata about photos. Manual annotation of photos is tedious and consumes large amounts of time. Automated content-based techniques such as face recognition rely on large training sets and are dependant on the illumination conditions at the scene of photo capture. Complimentary context-based approaches provide a lightweight, scalable solution to support the abstract way in which users actually think about photos. Further reading