A method for halftoning a gray scale image to generate a halftoned image
uses a stochastic screen is designed to provide visually pleasing, blue
noise dot profiles when thresholded at any gray level and wherein
substantially all the threshold values corresponding to gray levels
between g.sub.s1 and g.sub.s2 coincide with black positions in a
constraining checkerboard pattern and substantially all the threshold
values corresponding to gray levels between g.sub.s2 and g.sub.s3
coincide with white positions in the constraining checkerboard pattern.