Abstract
When we see a binary black and white image, it appears, to our visual sense, to become clearer because of a pseudo halftone. We presented a theory and experimental results for layered model which extended external world, retina and brain of the one dimensional visual model, the equivalence approximation method of two dimension based on one dimensional visual model. We obtain experimentally the restored images, the measure of approximation of density four division method, ordered dither method, random dither method and least mean error method. The measure of approximation presents the objective estimation scale to coincide with the subjective estimation of the four modulation images by the equivalence approximation method. We presents the image estimation method which is no significant difference between its method and two dimensional model. Generally, we believe the measure of approximation is effective the arbitrary two value modulation images.
