Quadtree decomposition is one of the methods of representing binary image data at multiple resolutions. Such representations have found application in many areas of image processing. This paper describes a novel implementation of quadtree generation using histograms. The histogram based implementation is fast and easy to implement on any histogram generating hardware. The number of histograms to be computed depends upon the size of the original image, the size of the smallest block into which the image is to be resolved, and on the number of gray levels handled by the histogram generating hardware. The paper also describes a fast algorithm to reconstruct binary images from quadtree decomposition using video rate lookup table processing.
S. G. Lele,
"Fast Quadtree Decomposition Using Histograms", Proc. SPIE 0697, Applications of Digital Image Processing IX, (10 December 1986); doi: 10.1117/12.976222; https://doi.org/10.1117/12.976222