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Skin face detection in photo imaging, is an important component of systems for detecting similarities in visual perception, tracing faces through illumination and metamerism. This paper presents an evaluation of the skin perception under standardized conditions of varied light sources: cool-white fluorescent “store light”, 6500K fluorescent “daylight”, and incandescent “home light”, Led light 6500 K, 2700K, 4000K CCT. In cases where the discrepancy is large, the resulting index of metamerism can be misleading. A small index of metamerism and a large change of color under illuminant metamerism has a different interpretation than what is perceived. This has been demonstrated through small colour variations in print through CMYK colors. The implication is that particular indices of metameric should only account for a limited range under different light conditions. The method used in this paper is based on visual perception, which aim to work with a wide variety of individuals, under varying lighting conditions under the influence of standard daylight, but in this case we also used the Led light 6500K correlated colour temperature, and variations of skin color tones, comparing the illuminant metamerism of visual perception based on different reflectance power distributions (SPDs).

Appropriate labeling and flexible packaging plays an important role on the today`s demands. There is diverse possibilities especially related to polymeric materials. Flexible packaging means to consider options such as OPP (Oriented Polypropylene), PVC (Polyvinyl Chloride), OPS (Oriented Polystyrene), PET (Polyethylene Terephthalate) or all kind of self-adhensive paper and foil types. Special highlight are the "Shrink Sleeve" labels that meet the most demanding market challenges. Its capabilities are beneficial. Laminated packaging materials are functional. Both constitute protection and packaging capacity. Coefficient of friction is the value that serves to meet the standard of how the flexible packaging material will glide and move on the packaging machine. This research is focused on the optimum quality of the packaging production process to meet all the preconditions for implementation of the semifinished product packaging and to avoid difficulties and possible stoppages on the packaging machine itself.

Knitted shirts are an appropriate carrier for easily readable information, and therefore, in recent years, QR Codes are very often printed on T-shirts. With the purpose of investigating QR Code fastness printed on textiles, in the paper a methodology was proposed for durability assessment of functionally printed knitted fabrics that includes the implementation of long-term care and wearing simulation - which the T-shirts are exposed to over the lifetime. Dimensional changes after multiple washing and drying cycles were determined for non-printed and functionally printed white knitting ; abrasion resistance and tendency to surface pilling after multiple rubbing cycles. The effect of usage simulation on functional prints durability was defined, as well as color fastness, readability and aesthetic properties. It was found that structure of knitted fabrics, their dimensional stability, the number of care and wear cycles performed, the printing technique and size of black modules in QR Code all have an influence on the results obtained.

Understanding the influence of UV varnishing on diversified tonality spot colors is significant in offset printing process. Versatility of various spot colors implies repeatability and correct reproduction. UV varnishing methods, besides enhancing the visual impact on the product, have a protective role, but due to the effect on different wavelengths spot colors can cause negative colorimetric changes. The research examined the impact of UV varnishing methods on printed spot colors on diverse printing substrates. The degree of change on prints caused by UV varnish was determined using spectrophotometric and densitometric methods. Research results are clearly showing the modality and the extent UV varnishing method causes on spot colors. This paper presents objective conclusions that help predict possible variations in spot colors, as well as limit values of colorimetric deviations that may affect the quality of the reproduction process.

Raznovrsne tehnologije tiskarskih procesa uzrokuju različita odstupanja u kvaliteti otisnutog grafičkog proizvoda. Etikete kao grafički proizvodi osjetljive su na takve promjene, budući najčešće predstavljaju prvi kontakt između kupca i proizvoda na koji je etiketa aplicirana. Ovo istraživanje usmjereno je na otiske kojima dominiraju tamnije boje, otisnute tehnikom ofsetnog tiska. Cilj ovih istraživanja je na osnovu spektrofotometrijskih mjerenja i vizualne ocjene kvalitete tiska, konstruirati MacAdamsove elipsoide i ustanoviti je li moguće MacAdamsovim elipsodima ustanoviti kvalitetu tiska u području tamnih boja. Nakon provedenih istraživanja, ustanovljeno je da elipsoidi pokrivaju različita područja unutar CIE L*a*b* sustava. Osim navedenog ustanovljeno je da je vizualnom procjenom moguće percipirati male promjene u tamnim bojama, ali ne u svim vrijednostima linearno. Korelacijom navedenih rezultata, zaključeno je da je prilikom ustanovljavanja kvalitete tiska tamnih boja moguće koristiti MacAdamsove elipsoide., Various technologies of printing processes induce various deviations in the quality of the printed graphic product. Labels as graphic products are sensitive to such changes, since they represent the first contact between the consumer and the product the label is applied on. This research is oriented towards imprints dominated by dark colours, printed using the offset printing technique. Goal of this research is to, based on the spectrophotometric measuring and visual evaluation of the printing quality, construct the MacAdams ellipsoids and establish whether it is possible to establish the printing quality in the area of dark colours using MacAdams ellipsoids. After conducted research it was established that the ellipsoids cover various areas within CIE L*a*b* system. By correlating the stated results, it was concluded that while establishing the printing quality of the dark colour it is possible to use MacAdams ellipsoids.

This study explores the applicability of micro- Raman spectroscopy as a non-destructive technique for the analysis of color toner printed counterfeits. The main aim of the research paper was to find out whether Raman spectroscopy is a suitable method for establishing the connection between different specimens of counterfeits suspected to be printed with the same toner on the same machine. Specimens of different types of toners printed on different types of paper are analyzed by means of the micro-Raman spectroscopy system with the excitation line at 514.5 nm. For each specimen cyan, magenta and yellow toners are analyzed separately. The yellow toners displayed the most distinctive Raman spectra. The results show that micro-Raman spectroscopy can be successfully applied as a method for the analysis of color toner printed counterfeits, such as banknotes and documents, in order to establish links between more or less different specimens of counterfeits by measuring the properties of a color toner.

There is often a phenomenon depending on dominant tones which results in the end users dissatisfaction with halftone color reproduction. This phenomenon is known as “metamerism” and it is the subject of research for many scientists. The metamerism on halftone color images with different dominant tones (blue, red, green and yellow) was researched in this paper, at the light sources D 50 , D 65 and daylight. The results of the objective and visual evaluation were presented on the basis of colorimetric measurement of the grey balance patch, by the means of MacAdam ellipsoids in three dimension CIE L * a * b * system. Both the metamerism index MI and the ellipsoid volume have also been calculated. This paper confirms that the metamerism of the halftone color images can be estimated by measuring CIE L * a * b * values of the grey balance patch and by calculating MacAdam ellipsoids.

Nowadays, flexographic printing process is the most cost-effective printing technique. Due to its capacity to produce very good print quality it is predominantly used for labelling and packaging applications. Additionally, flexography has become a very strong competition to the gravure printing process in performing more demanding printing tasks. In order to improve reproduction quality obtained by flexographic printing technique, some modifications in producing printing plates have been developed in the recent years. In this paper, two new technologies, DigiCap and SquareSpot, are presented. The aim of the research was to analyse and define the quality of reproduction obtained with DigiCap and SquareSpot technologies in the production of printing plates. The definition of the overall reproduction quality was determined using objective and subjective analysis. Three image quality attributes were observed: line reproduction quality, circularity of dots and dot gain in objective analysis.

Čitljivost predstavlja glavni problem u označavanju različitih potrošačkih proizvoda. Veličina pisma određuje čitljivost teksta i ima ključnu ulogu u performansama čitanja. Raspon korištenih veličina pisama koji su u općoj upotrebi na deklaracijama proizvoda, a manji su od optimalnih veličina i izvedeni u suženom pismovnom rezu, uzeti su kao temeljni elementi analize u radu. Vidljivost pod uvjetima umjetnog osvjetljenja, brzina čitanja, stopa pogrešaka i zastajanje prilikom čitanja predloženi su kao kriteriji ocjenjivanja čitljivosti. Istraživanje je provedeno iz dvije različite perspektive vidnog statusa čitatelja. Ovim se radom, znanstvenim metodama istraživanja, nastojalo ukazati na upotrebljivost malih veličina na proizvodima i potreba da iste budu što čitljivije., Legibility represents the main issue in the labelling of various consumer products. Font size determines the legibility of the text and plays a crucial role in the reading performance. The range of font sizes that are commonly used in product labelling and that are smaller than the optimal size and constructed in condensed font were taken as the basic elements of this article. Visibility depending on artificial light, reading speed, error rate, and pausing during reading, have been suggested as the criteria for legibility evaluation. The survey was conducted from two different perspectives based on the visual status of the reader. With this paper and the scientific methods of research used in it, the intention was to show usefulness of small font size on the product labels and the necessity of making them more readable.

Light and gas fastness are two very important aspects of print quality. The aim of this proceeding is to determine light and pollutant impact on the gamut of prints through exposure of samples to artificial, glass filtered and direct sun-light, as well as common gas pollutants. Exposed samples were analysed by densitometric and spectrophotometric methods and statistically processed in order to determine the correlation between time and type of exposure and gamut changes. The results show a significant impact of combined direct sunlight and pollutants on prints. Beside the scientific aspect, these results could be used as guidelines for manufacturers and printers to improve the quality, while still maintaining low production costs.

Visokopigmentirane boje imaju mogućnost s tanjim slojem boje prekriti rasterske elemente pri čemu je intezitet njihova obojenja veći u odnosu na klasične boje. Upotrebom takvih boja otisci dosegnu točku gdje se prirast rastertonske vrijednosti i prostor reprodukcije mijenja, a koja je usko povezana s granicama kvalitete otiska. Ovo je također izravno povezano sa standardizacijom tiska i ponovljivosti tiskarskog procesa. Upravo zbog toga naše istraživanje smo usmjerili na povećanje kvalitete reprodukcije upotrebom visokopigmetiranih boja. Otiskivanje je provedeno na dvije vrste papira koji se najčešće koriste u tehnici ofsetnog tiska. U ovome radu, kvaliteta reprodukcije vizualno je ispitivana s promjenjivim vrijednostima gustoće obojenja, prirastom rastertonskih vrijednosti i gamutu boja. Ovaj rad sadrži također i nove, preporučljive vrijednosti prirasta rastertonske vrijednosti i prostora reprodukcije boja kada se otiskivanje obavlja korištenjem visokopigmentiranih boja., Highly pigmented inks have the ability to cover screen elements with a thinner layer of ink applied whereby the intensity of their inking is higher compared to the classical inks. When using such inks, the printing reaches the point where the ink dot gain and the space of reproduction changes, which is closely related to the limits of the print quality. This is also directly related to the standardization of the print and the repeatability of the process. For this reason our research is focused on increasing the reproduction quality by using highly pigmented inks. The printing was carried out on two types of paper that were most commonly used in offset printing technology. In this paper, the reproduction quality was visually determined at changeable values of the inking densities, dot gain and gamut of colour. This paper also contains the new, recommended values of dot gain and gamut for printing processes using highly pigmented inks.

Izrada modnog kataloga važan je čimbenik u plasmanu proizvoda koje katalog prezentira. Prezentacija proizvoda u katalogu mora biti objektivna, ali mora i privući potencijalnog kupca. Zbog toga se postavlja pitanje može li se modni katalog izraditi tako da se zadovolje sve karakteristike u smislu objektivnosti i subjektivnosti kada je u pitanju doživljaj boja. Doživljaj boja u prvom jeredu uvjetovan rasponom tonaliteta koji je direktno ovisan o gustoći obojenja upotrijebljenih bojila za tisak. Cilj ovoga rada je utvrditi korelaciju objektivnog i subjektivnog ocjenjivanja kvalitete tiska modnog kataloga. U tu svrhu otisnuti su motivi kojima se može dobiti navedena korelacija. Objektivna ocjena kvalitete tiska dobivena je mjerenjem trodimenzionalnih vrijednosti boja koji je moguće u katalogu reproducirati, dok je subjektivna ocjena kvalitete kataloga utvrđena analizom frekvencije doživljaja kvalitete tiska kataloga. Na temelju rezultata utvrđeni su parametri i granični uvjeti koje je potrebno zadovoljiti kako bi se katalog otisnuo u optimalnoj kvaliteti., The production of the fashion catalogue is important factor in the placement of the products the catalogue presents. The product presentation in the catalogue must be objective, but it must also attract the potential customer. Because of that, the question is set, if the fashion catalogue must be made so, to satisfy all the characteristics in the sense of objectivity and subjectivity in regard to the colour experience. Colour experience is first of all caused by the tonal range which directly depends on the inking density of inks used in printing. The aim of this work is to establish the correlation of the objective and the subjective evaluation of the fashion catalogue printing quality. For this purpose, the motives are printed, by means of which it is possible to determine the mentioned correlation. The objective evaluation of the printing quality was established after the measurements in the three dimensional colour space which is possible to reproduce in the catalogue, while the subjective evaluation of the catalogue quality was established by the analysis of the experience frequency of the catalogue printing quality. Based on all results, the parameters and boundary conditions have been established which must be satisfied in order to print the catalogue in optimal quality.