Representation of multi-resolution symbolic and binary pictures using 2D H-strings

A type of quadtree data structure, called a 2D H-string, is proposed for representing symbolic and binary pictures. The approach has an embedding property that allows for spatial-relational operators to be easily inserted into the structure. Algorithms are presented for traversing 2D H-strings to carry out the processing needed and for intersecting two pictures directly on their 2D H-string representations. The space complexity of 2D H-strings is analyzed and compared with other quadtree data structures. It is shown to be efficient in terms of space complexity and effective in terms of cooperativeness with other spatial-relational operators