Method for Visual Color Matching in Image Reproduction Systems

U ovom radu razmatra se problem prikaza boja u različitim uvjetima promatranja. Dane su osnove teorije doživljaja boje i kolorimetrije. Opisane su pojave koje utječu na prikaz boja. Kromatska adaptacija je najvažnija osobina vizualnog sustava, koja ima važnu ulogu u modelima za prikaz boja. Model kromatske adaptacije omogućuje predviđanje odgovarajućih boja. Opisana su dva modela kromatske adaptacije: von Kriesov model i Fairchildov. Dan je pregled dva modela prikaza boja: Huntov i CIECAM02. Provedena su vizualna ispitivanja izjednačenja slika na monitoru s otisnutim slikama. Izjednačenje je provedeno metodom istodobnog promatranja. Uvjeti promatranja su se razlikovali u točki bijelog, pozadini, nivou luminancije i okruženju. Dobiveni podaci su usporedili s odgovarajućim bojama izračunatih pomoću četiri linearne transformacije. Predložena nova linearna transformacija pokazuje bolje slaganje za neke boje.The color appearance in different viewing condition is the main topic of this work. An overview of the color theory and colorimetry are given. Several color-appearance phenomena are described. Chromatic adaptation is the most important property of the human visual system with respect to understanding and modeling color appearance. A chromatic-adaptation model allows prediction of corresponding-colors data. Two models of chromatic-adaptation transformations are described: von Kries´s and Fairchild´s. An overview of two color appearance models, Hunt´s and CIECAM02, is given. Psychophysical experiments were carried out by comparing soft-copy and hardcopy images employing simultaneous binocular viewing. The conditions varied in white point, background, luminance level and surround. The experimental data obtained were compared with corresponding colors predicted with the use of four types of linear transforms. A new linear transform is suggested. The results show improvements for some colors