This is a good question with many possible answers.

A straightforward, quite simple segmentation of handwritten Arabic characters by selecting k generating points from a handwriting image and then construction a Voronoi diagram like the ones in

http://mathworld.wolfram.com/VoronoiDiagram.html

implemented in Mathematica 10 with

https://reference.wolfram.com/language/ref/VoronoiMesh.html

See the image processing section of the Wolfram language page.    For a Matlab implementation, see

http://www.mathworks.com/help/matlab/ref/voronoi.html

For helpful articles on Voronoi meshes, see

https://www.researchgate.net/publication/2619574_The_Graph_Voronoi_Diagram_with_Applications

https://www.researchgate.net/publication/220110156_The_Voronoi_Diagram_of_Circles_and_Its_Application_to_the_Visualization_of_the_Growth_of_Particles

Article The Graph Voronoi Diagram with Applications

Article The Voronoi Diagram of Circles and Its Application to the Vi...

many thanks