METHOD OF ESTIMATION OF PRINTED PICTURES ON MEDIUM Russian patent published in 1998 - IPC

FIELD: printing industry. SUBSTANCE: the method involves operations of readout of a reference picture visually preestimated as a reference one by means of an optoelectronic reader; the reference picture is divided into elements of picture, memory of each picture element by means of a memory unit, readout of checked printed pictures and comparison of their picture elements with memorized elements of the reference picture with due account made for specified values. The result is attained due to the fact that optical density is taken as the value for comparison, several reference pictures are selected, and an individual upper and/or lower limit of optical density for each picture element is determined with the help of them, these limits are used in subsequent comparison of checked pictures. EFFECT: enhanced quality of read out pictures. 5 cl, 2 dwg