Conceptual, spatial and temporal referencing of multimedia objects

The increasing usage in GIS of multimedia objects, such as scanned photographs and video recordings, has introduced the need to provide flexible indexing methods to help in accessing objects that may be of relevance to a range of possible applications. An experimental system is described in which media objects may be referenced to several classifications concepts, as well as qualitative descriptions of geographic location and time period. Semantic modelling techniques are used to create semantic networks that represent the hierarchical and lattice structures of conceptual, temporal and geographic space. The associated query methods enable inexact matching between user interests and the media object descriptors. Several metrics of semantic closeness, in concept, time and geography have been developed, based on scaled measures of path lengths within the semantic networks that represent the three dimensions of indexing.