From Where to What: Metadata Sharing for Digital Photographs with Geographic Coordinates

We describe LOCALE, a system that allows cooperating information systems to share labels for photographs. Participating photographs are enhanced with a geographic location stamp -- the latitude and longitude where the photograph was taken. For a photograph with no label, LOCALE can use the shared information to assign a label based on other photographs that were taken in the same area. LOCALE thus allows (i) text search over unlabeled sets of photos, and (ii) automated label suggestions for unlabeled photos. We have implemented a LOCALE prototype where users cooperate in submitting labels and locations, enhancing search quality for all users in the system. We ran an experiment to test the system in centralized and distributed settings. The results show that the system performs search tasks with surprising accuracy, even when searching for specific landmarks.