ZACRNJENJA GRAYSCALE ZAPISA KONVERTIRANOG RGB ZAPISA FOTOGRAFSKE SLIKE

DARK SHADES DENSITIES OF A GRAYSCALE IMAGE RECORD CONVERTED FROM RGB PHOTOGRAPHIC IMAGE RECORD

Darija Ćutić1, Miroslav Mikota2, Teo Žeželj2

1 Tehničko veleučilište u Zagrebu,
2 Grafički fakultet u Zagrebu

darija.cutic@tvz.hr, miroslav.mikota@grf.hr, teo.zezelj@grf.hr

 

Sažetak

Snimanjem digitalnim fotografskim aparatom se danas najčešće stvaraju RGB digitalni zapisi fotografskih slika. Ako se takva, kolor, fotografska slika konvertira u crno-bijelu, tj. Grayscale zapis, gube se podatci o bojama izraženi kao vrijednosti R, G i B kanala, ali su pri tome pojedine boje konvertirane u određena zacrnjenja. U ovom se radu analiziraju zacrnjenja dobivena konverzijom RGB zapisa fotografske slike u Grayscale zapis. Konverzija je provedena na tri fotografske slike standardnim postupkom direktne konverzije u Adobe Photoshop programu. Uz konverzije tri realne fotografske slike, provedena je i konverzija standardne tablice boja. Dobivena zacrnjenja su analizirana kroz vrijednost svjetline (L).
Ključne riječi: RGB sustav, Grayscale sustav, zacrnjenje, svjetlina

 

Abstract

Today by shooting with digital camera most commonly is crated RGB recording of a digital photography. If such a colour photography is converted to a black and white image or in to the Grayscale record, colour data which is expressed as the R, G, and B values of the channel, is lost, but certain colours are converted to certain dark shades. This paper analyses the dark shades density obtained by converting the RGB image record to the Grayscale record. Conversion was performed on three photo images by a standard direct conversion process in Adobe Photoshop. Beside the conversion of three realistic photographic images, a standard colour table conversion was also performed. The obtained dark shades densities were analysed by the luminance value (L).
Keywords: RGB system, Grayscale system, dark shades density, brightness