NPR（Non-Photo-realistic Rendering）是近年來在影像處理範疇中發展相當快速之一項研究課題，主要目的是以電腦、演算法自動產生類似素描、水彩及油畫之類，輸出與一般照片不同類型事物。與其處於另一極端為PR（Photo-realistic Rendering），其目標是追求以電腦產生接近真實事物為最重要目的，所產生事物越成功，表示程式越成功，如Matting或Inpainting。NPR可進一步根據實體模型（Physical Model）之有無來細分，若有實體模型，則依據實體模型特性，以電腦程式模擬，其結果會較為良好；反之，若無實體模型，則需憑藉研究者思考與觀察，盡可能找出更多正確資訊，來模擬求得最後結果，本研究屬於NPR中Non Physical Model中一環。將藝術家對相片作水彩畫或油畫之想法，轉換成電腦演算法產生。
根據畫家說法，繪畫即是光與陰影之表現，以現在科學角度而言，其實就是亮度強弱之表現。而從亮度這項資訊中，亦可分離出許多供畫家參考依據，例如繪圖區塊、繪圖方向…等，而NPR可以說是一步步實現畫家作品之一門研究。繪畫，根據使用繪畫工具及技巧不同又可分成不同繪畫藝術風格。本研究主要模擬印象派油畫。

NPR (Non-Photo-Realistic Rendering) is a new and quick-developed research topic in Image Processing. The main purpose of NPR is to generate pencil sketching、watercolor and oil painting, something different from photos, automatically by computer algorithms. On the other hand, there is another technique called PR (Photo-Realistic Rendering). The goal of PR is to generate real objects by computer algorithms, such as Matting or Inpainting.
Furthermore, NPR includes two modes：one is with physical model, researchers could write programs to simulate NPR by the properties of physical model. Without physical model, researchers could write programs to simulate NPR by their observation and deliberation. This thesis to the latter, there is no physical model in NPR.
In the viewpoint of artists, drawing is performance of light and shadow. Then, in scientific, drawing depends on the degree of luminance. Luminance supports artists block and direction when drawing. Moreover, This thesis is mainly simulating oil painting with impressionist.

目錄0
第一章簡介1
第一節序論1
第二節繪畫工具8
第三節色彩理論及色彩模型10
第四節科技影像與藝術發展15
第五節繪畫藝術風格17
第二章理論依據21
第一節非真實照片式繪圖（Non-Photorealistic Rendering）21
第二節影像增強22
第三節色調量化27
第四節水彩畫及油畫28
第三章實際操作方法、步驟與結果31
第一節影像增強31
第二節色調量化32
第三節擷取影像資訊33
第四節基本筆觸繪畫37
第五節邊緣筆觸繪畫41
第四章未來工作43

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