METHOD AND APPARATUS FOR QUANTIFYING VISUAL SHOWTHROUGH OF PRINTED IMAGES ON THE REVERSE OF PLANAR OBJECTS

摘要

An image analysis method and apparatus (10) having an imaging assembly (12) and a processor (14) to quantify visual showthrough of printed images on the reverse face of planar objects, such as paper. An illumination level is set using a white reference object. A white reference image is stored in a computer memory. An image of a planar object having a printed image on the reverse face is stored in a computer memory. A pixel by pixel ratio of the two images is calculated and a mean value of the ratios is calculated to characterize the visual showthrough. The measurements are substantially independent of both the illumination level and image shading.