State of the Geotag: where are we?

Assigning location information to online media has grown from a fringe activity to an automated process aided by supportive hardware and software. This has lead to increasing availability of geographic context for the picture, videos and audio users share on the web. Such data has allowed systems to search through, browse and analyse media according to location without being wholly dependant on expensive manual annotation. However, the current extent of much geographic metadata consists of describing a single pair of coordinates per item. There is difficulty in encoding the multiple locations pertinent to the content of an image, the location of the camera, as well as handling the multiple locations that may be associated with sections of video. Current media retrieval systems use geographic indexing to return results that are relevant to an area defined as within the radius of a point or an official bounding box. This ignores the complexity of canonical geographic boundaries, as well as the colloquial nature of many commonly-referred to geographic points and areas, highlighting the relationship between these two complementary geographies. By addressing these current limitations, future geographic multimedia retrieval systems will be able to better support user engagement with media.