臺灣博碩士論文加值系統

SD (super-deformed) 源於日本漫畫與動畫，是一種誇張化角色使其看起來更為可愛的特殊風格。SD風格的角色被廣泛應用在各個領域，常見於許多動畫、圖學電影，或是遊戲。然而，創造一個SD風格的三維角色模型常需要專業技術與大量的時間及功夫。本論文提出一個將平常的三維角色模型轉換成具有SD風格的三維角色模型的技術。我們觀察到一些SD風格的特性，然後根據這些特性推導出能量函式並最佳化。使用者也可以給定一些與身體比例有關的參數與強化角色特徵來客製化角色。透過我們的技術，即使是剛接觸我們技術的使用者也可以在數秒以內創造一個視覺上令人感覺舒適的結果。

Super-deformed, SD, is a specific artistic style for Japanese manga and anime which exaggerates characters in the goal of appearing cute and funny. The SD style characters are widely used, and can be seen in many anime, CG movies, or games. However, to create an SD model often requires professional skills and considerable time and effort. In this thesis, we present a novel technique to generate an SD style counterpart of a normal 3D character model. Our approach uses an optimization guided by a number of constraints that can capture the properties of the SD style. Users can also customize the results by specifying a small set of parameters related to the body proportions and the emphasis of the signature characteristics. With our technique, even a novel user can generate visually pleasing SD models in seconds.

Acknowledgments i
致謝ii
中文摘要iii
Abstract iv
1 Introduction 1
1.1 Introduction of SD . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 Proposed System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.4 Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.5 Thesis Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 Related Work 6
2.1 Mesh Deformation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Geometry Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.3 Artistic Stylization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3 SD Stylization 10
3.1 Character Model and Embedded Skeleton . . . . . . . . . . . . . . . . 13
3.2 Skeleton Deformation . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.3 Mesh Deformation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3.3.1 Body Proportion Constraint . . . . . . . . . . . . . . . . . . . 18
3.3.2 Primitive Fitting Constraint . . . . . . . . . . . . . . . . . . . 22
3.3.3 Detail Smoothing Constraint . . . . . . . . . . . . . . . . . . . 23
3.3.4 Signature Characteristic Constraint . . . . . . . . . . . . . . . 24
3.3.5 Total Energy and Optimization . . . . . . . . . . . . . . . . . . 30
4 Results and Discussion 33
4.1 Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.2 User Study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.3 Limitation and Future Work . . . . . . . . . . . . . . . . . . . . . . . 48
5 Conclusion 52
Bibliography 53

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