Adaptive representation of histogram using interval tree

Proposes a new data structure, called histogram interval tree, to represent a distribution of gray levels in terms of intervals over a given gray-level range. The proposed structure will allow a user to refine the intervals adaptively as needed in each individual application. The author demonstrates that by using this new representation, the interactive specification of desired histogram becomes particularly easy and effective. Results from the proposed technique is compared with that from existing techniques for image enhancement using histogram transformation. The applications of the histogram interval tree can be extended when certain properties associated with histograms are attached to the tree. The author illustrates an example of such extension by building a threshold hierarchy for image segmentation