Edge Process Models for Regular and Irregular Pixels

摘要

This report shall focus attention on the specification of the edge process, and show how various geometrical insights suggests how the prior Gibbs distribution should be constructed. The discussion will suggest relative costs for possible configurations somewhat different from those proposed by Geman and Geman (1984). In addition, the scheme will provide methods for dealing with rectangular and irregular pixel patterns. The general idea of evolving penalties for continuation configurations based on a conditional expected projection length can of course be extended to more general polygons in the dual tessellation. The advantage of the projection approach is that consistent penalties can be written down for cliques of different kinds that appear in different parts of the same pattern. Thus the circular pixel grid contains some vertices of degree 3, which can be dealt with using the formulas derived and some of degree 4 whose dual polygons in the dual tessellation are for all practical purposes, rectangles-which are treated in this section.