Uporaba metode glavnih komponent za generiranje prenosnih funkcij pri upodabljanju 3D volumnov

DROFENIK, ANDREJ (author), Marolt, Matija (mentor), Lesar, Žiga (co-mentor)

Upodabljanje volumnov je postopek, s katerim volumen projiciramo na platno. Bistveno vlogo pri tem igra prenosna funkcija, ki pretvori točke volumna v optične lastnosti projekcije (npr. barvo in prosojnost). S spreminjanjem prenosne funkcije lahko uporabnik izbira, katere elemente volumna želi prikazati ali izpostaviti. Določanje dobre prenosne funkcije za izpostavljanje želenih delov volumna je za povprečnega uporabnika nepriročno in zamudno. Za takšne primere je smiselna izdelava orodij za generiranje prenosnih funkcij. V diplomskem delu smo razvili model, s katerim uporabniku generiramo prenosne funkcije s pomočjo metode glavnih komponent. Izdelali smo aplikacijo z uporabniškim vmesnikom za urejanje prenosnih funkcij, ki je med uporabo beležil prenosne funkcije. Po zbiranju podatkov z aplikacijo smo le-te analizirali, obdelali in pripravili za uporabo v modelu. Model smo izdelali in ga vključili v ogrodje za vizualizacijo volumnov. S posodobljeno aplikacijo lahko uporabniki izbirajo med predlaganimi prenosnimi funkcijami, ki so generirane na podlagi shranjenih podatkov.

• Language: Slovenian
• Keywords: računalniška grafika, volumen, upodabljanje, prenosna funkcija, metoda glavnih komponent, uporabniški vmesnik
• Work type: Undergraduate thesis
• Organization: FE - Faculty of Electrical Engineering
• Year: 2021
• PID: 20.500.12556/RUL-130388
• COBISS.SI-ID: 77353987
• Publication date in RUL: 14.09.2021

Secondary language

• Language: English
• Title: Using principal component analysis for transfer function generation for 3D volume rendering

Abstract

Volume rendering is a procedure used to visualize two-dimensional projections of three-dimensional data sets. Paramount to this technique is the transfer function, which assigns optical properties to points inside the volume (e.g. color and transparency). By changing the transfer function, the user may choose what data to display or highlight. Selecting or changing the parameters of the transfer function is unintuitive and time-consuming for the average user. For such cases, using tools to generate transfer functions is helpful. In this work, we developed a model that generates transfer functions with the help of principal component analysis. A user interface, specialized in displaying and collecting transfer function parameters was developed. When a sufficient amount of data was obtained, it was analysed and restructured for further use. Then, the model was developed and installed into the VPT framework for volume visualization. With the update, users can now choose between suggested transfer functions, generated based on collected data.

• Keywords: computer graphics, volume, rendering, transfer function, principal component analysis, user interface