have recently developed a case based reasoning system for offset print quality control. Developments in this area usually concern creation of print quality test pages (Jang, Chen, Allebach, & Chiu, 2004), simulation of the most common print quality defects (Jang & Allebach, 2005 Kowalczyk & Trksak, 1998), inspection of one or several print quality attributes, such as the actual size and quality of printed dots (Antoine, Lloyd, & Antoine, 2001 Bergman, Verikas, & Bacauskiene, 2005 Chuang & Lai, 1997), mottling (Sadovnikov & Lensu, 2007 Sadovnikov et al., 2005), CCD camera-based estimation of ink density (Brydges, Deppner, Kunzli, Heuberger, & Hersch, 1998 Verikas & Bacauskiene, 2008), automatic detection and classification of various printing defects (Perner, 1994), print graininess (Trepanier, Jordan, & Nguyen, 1998). Since the manual procedures are tedious, time consuming, and the results are subjective as they depend on personal skills and mood, automated printing quality inspection systems are highly appreciated.

Colour print test page pdf