如何精準的描述材質所帶給人的視覺感受，一直以來都是許多研究人員致力於解決的問題，在工業設計及產品品質日益受到重視的今天，CMF(Color Material Finish)領域更是對於如何精準的掌握材質特性有著極大的需求。為了解決此問題，國際照明委員會透過定義材質視覺外貌(Visual appearance)此一名詞，來描述每一材質所擁有的四種屬性，分別為色彩、紋理、光澤度及透光度，藉由對此四種屬性進行定量的分析來達到材質描述的目的。本論文期望藉由建置一個SVBRDF(Spatially Varying Bidirectional Reflectance Distribution Function) 的量測系統，透過一系列控制下的多角度光源與相機之間對材料的取像資料，來還原非金屬材質的視覺外貌屬性。
為了達到視覺化量化結果的目的，本研究希望透過擬真渲染的方式，來達到材質描述的目標。因此本研究將材質視覺外貌中所定義的屬性與圖學渲染中目前主流的渲染流程PBR (Physically-Based Rendering)建立起之間的關係。對於目前主流之一的Metallic Roughness 渲染流程，其定義了對材質所需的基本4種屬性貼圖，分別為基本色貼圖、表面法向量貼圖、粗糙度貼圖及金屬度貼圖。藉由將視覺外貌的定量分析參數化至PBR中所定義的不同屬性的紋理貼圖中，來完成最終對於材質的擬真渲染。本研究量測了3種不同種類的材質共計10個樣品，並抽取其所擁有的各屬性貼圖，最後透過渲染的方式來呈現對不同屬性量化的成果。

How to accurately describe the visual experience brought by materials has always been an issue that many researchers are trying to solve. Nowadays, to increase the value industrial product, the field of CMF (Color Material Finish) needs more accurate mastery of material characteristics. In order to solve this problem, CIE (Commission Internationale de’Eclairage) defined visual appearance. Visual appearance consists of the properties of color, texture, gloss, and transparency that are evaluated by the approach of the quantitative analysis. Based on quantitative analysis, four attributes to achieve the purpose of material description. In this thesis, we proposed a practical solution to restore the visual appearance of non-metallic materials by constructing a SVBRDF (Spatially Varying Bidirectional Reflectance Distribution Function) measurement system, with a series of controlled multi-angle light sources and camera image data.
In order to get the quantitative results, this study describes the target of material by photo realistic rendering method. Therefore, this study establishes the relationship among those attributes defined in the visual appearance of materials, and utilizes the current mainstream rendering process, which is the metallic roughness workflow of PBR (physically based Rendering), for visual reproduction. In the workflow, the four basic attribute maps, called color, normal, roughness and metallic maps, are required to represent the material. The realistic rendering of specific materials is carried out by quantifying the attributes of the texture map. This study tested three kinds of material commas of 10 samples. Finally, the graphical reproductions are evaluated by verifying the rendering of different attributes.

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