A 3D-Hash Function for Fast Image Indexing and Retrieval

Image retrieval on the basis of similarity is an important task in many image database applications. Majority of the users´ requests requires retrieving those images in the database that are spatially similar to the query image. In image databases, images are represented by symbolic images. Spatial relationships in a symbolic image are represented by 2D strings. In Image Database Systems, conventionally 2D strings that are converted into triples represent symbolic pictures or objects. A unique hash address is assigned to each triple, which represents the picture. It serves the purpose of retrieval of images by reducing pattern matching. The calculation of new unique hash keys for all triples is required while inserting new image. In order to overcome these problems we present a solution in this paper that is the concept of a 3D hash function which speeds up the computation of the associated values for the picture objects.