Overview of the ImageCLEFphoto 2007 Photographic Retrieval Task.

The general photographic ad-hoc retrieval task of the ImageCLEF 2007 evaluation campaign is described. This task provides both the resources and the framework necessary to perform comparative laboratory-style evaluation of visual information retrieval from generic photographic collections. In 2007, the evaluation objective concentrated on retrieval of lightly annotated images, a new challenge that attracted a large number of submissions: a total of 20 participating groups submitted 616 system runs. This paper summarises the components used in the benchmark, including the document collection and the search tasks, and presents an analysis of the submissions and the results.