Content based image retrieval: related issues using Euler vector

A combinatorial characterization of a gray-tone image called Euler vector is discussed. The Euler vector comprises a 4-tuple, where each element is an integer representing the Euler number of the partial binary image formed by the four most significant bit planes of the gray-tone image. The vector is topologically invariant and can be used for image indexing and retrieval. The Euler vector for all the images in the database can be arranged using any multidimensional data structure. For retrieval, a query range is to be defined around the query image vector. We use a simple statistical technique to specify the query range. Next, we propose a modification in the Kd-Tree construction to build a simple hybrid tree that supports efficient adaptive clustering and indexing. The same data structure is used for clustering and indexing.