Uporaba enovitega modela barvnega zaznavanja pri upodabljanju barv v statični tridimenzionalni računalniški grafiki

Bratuž, Nika (author), Javoršek, Dejana (mentor), Gabrijelčič Tomc, Helena (co-mentor)

Kljub tehnološkemu napredku zadnjih stoletij in desetletij se še vedno soočamo s problematiko prikaza in upodobitve barve na različnih medijih ter ohranjanja zaznave barve. Ena izmed možnosti, po kateri lahko posežemo pri zagotavljanju konstantne barvne zaznave, so modeli barvnega zaznavanja. Trenutno je aktualen CIECAM02, ki ima sicer velik potencial, a v praksi še vedno ni uporabljen, tudi v povezavi s 3D računalniško grafiko, s katero se prav tako soočamo skoraj vsakodnevno. Namen disertacije je bil preučiti napredno barvno metriko in model barvnega zaznavanja CIECAM02 do te mere, da bi ga lahko uporabili v povezavi s 3D računalniško grafiko. Ob tem smo predpostavili, da bo CIECAM02 uporaben tudi v 3D prostoru. Izkazalo se je, da tudi pri izrisu končnih 2D vizualizacij na upodobitev barve vplivajo številni parametri in nastavitve, ki vplivajo na računske operacije in algoritme izrisa. Testne postavitve smo v programskem orodju Blender upodobili s tremi upodobljevalniki: Blender Render in Cycles, ki sta že vgrajena ter z vtičnikom YafaRay. Rezultati so pokazali, da vsi upodobljevalniki na barve ne vplivajo enako, da model barvnega zaznavanja CIECAM02 lahko uporabimo v 3D prostoru in da z njegovo uporabo dobimo boljše rezultate ujemanja barv pri spremembi svetlosti ozadja. Model barvnega zaznavanja CIECAM02 uporabimo tako na barvah v 3D prostoru kot na že izrisanih 2D vizualizacijah.

• Language: Slovenian
• Keywords: 3D računalniška grafika, model barvnega zaznavanja, CIECAM02, upodabljanje barve, upodobljevalnik
• Work type: Doctoral dissertation
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Year: 2019
• PID: 20.500.12556/RUL-113142
• Publication date in RUL: 06.12.2019

Secondary language

• Language: English
• Title: Application of uniform color appearance model to color rendering in static three-dimensional computer-generated graphics

Abstract

Despite several technological advancements in the last few decades, we are still encountering issues regarding the reproduction of colors on different media and the achievement of color constancy. A possible option of ensuring constant color appearance are color appearance models, namely, the current color appearance model CIECAM02, which, despite having a great potential, is still not fully applied to practical workflows, especially in 3D computer generated graphics we come across on a daily basis. The purpose of this dissertation was to examine advanced color metrics and the CIECAM02 color appearance model to the point where it could have been implemented to 3D computer generated graphics. It was assumed that the CIECAM02 color appearance model can be used in 3D space, but it turned out that different setup parameters and settings influence the rendering calculations and algorithms which can, in turn, affect the rendering of color, too. Test setups were rendered with Blender software and three different rendering engines, namely, Blender Render, Cycles and the plug-in rendering software YafaRay. It was determined that rendering engines do not render color equally, that the CIECAM02 color appearance model can be applied to 3D computer generated graphics, and that by using the CIECAM02 color appearance model, we can significantly improve color matching when changing the lightness of the background. The CIECAM02 color appearance model can be successfully implemented on colors in 3D setups, or can be applied to already rendered 2D visualizations.

• Keywords: 3D computer generated graphics, color appearance model, CIECAM02, reproduction of color, rendering engine