A method of describing an image made up of a plurality of kinds of regions in an n-dimensional space by a tree structure, comprises the steps of recursively and equally dividing the image into 2.sup.n regions until each region includes two or less kinds of regions, thereby making a first level of the...http://www.google.fr/patents/US4944023?utm_source=gb-gplus-shareBrevet US4944023 - Method of describing image information
