PROCEDURE FOR PRODUCING A REFERENCE MODEL INTENDED TO BE USED FOR AUTOMATICALLY CHECKING THE PRINTING QUALITY OF AN IMAGE ON PAPER

A procedure for producing a reference model for checking the printing quality of an image composed of at least two drawings starts with printed test sheets. The sheets are aligned so that drawings printed in a first printing are in register. The images are recorded, storing the densitometric pixel values which constitute the images in memory. The minimum value obtained is associated with each pixel and a model for the first drawing is obtained. The same procedure is followed for producing a second drawing and another model. The models thus obtained are recombined in order to form the reference model of the image to be checked.