Resolution of problem with use of closing for texture segmentation

The morphological closing operation is widely known to be useful for separa ting regions containing high and low densities of particles. It is shown th at the area of the region of high density becomes enlarged as the density o f particles in the low density region increases - an effect that also occur s if impulse noise appears. It is found that the size increase is calculabl e and can approximately be cancelled by application of a suitable additiona l erosion operation, thereby improving the accuracy of the final representa tion.