Halftoning with minimum spanning trees and its application to maze-like images

We propose a method for generating halftone images by using minimum spanning trees (MSTs). We generate a stippling from an input image by using centroidal Voronoi tessellation (CVT), and then connect all the points in the stippling with an MST. We derive a relationship of darkness between the input image and the MST halftone image by approximating CVT with the hexagonal lattice, and utilize it for correcting the brightness of the MST halftone images. We also propose methods for generating maze-like images on the basis of the MST halftone images. We embed user-specified solution paths in the MST halftone images in two ways. Experimental results show that the solution paths are successfully embedded and hidden in the maze-like images.