A method of generating a binary Sel plane for image compression is
disclosed. The method first generates a 2 bit gray selector (GraySel).
This 2 bit selector is then processed in a second stage to produce a
binary Sel decision which minimizes the compression noise evident in the
reconstructed image. The method used here to generate the 2 bit GraySel
applies a set of prioritized rules over a small 3.times.3 window that is
well suited for segmenting synthetic, PDL generated images that are
typically free of scanner noise. The method not only marks the proper
sense of the selector when it is known, but also include a 3.sup.rd state
that indicates that the selector decision is weak or unknown. This weak
decision can then be optimized in the second stage process based on
strong edges information in the neighborhood.