  In this paper, region based and location based retrieval systems have been
implemented for retrieval of MR-T2 axial 2-D brain images. This is done by
extracting and characterizing the tumor portion of 2-D brain slices by use of a
suitable threshold computed over the entire image. Indexing and retrieval is
then performed by computing texture features based on gray-tone
spatial-dependence matrix of segmented regions. A Hash structure is used to
index all images. A combined index is adopted to point to all similar images in
terms of the texture features. At query time, only those images that are in the
same hash bucket as those of the queried image are compared for similarity,
thus reducing the search space and time.
