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SD Models:Super-Deformed Character ModelsSheng-Jie LuoLiang-Tsen Shen Bing-Yu ChenChiun-Kai

HuangNational Taiwan University

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SD

1

7

1

2.5

© Crypton Future Media, INC.

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Applications

Ahmed lumei

© Rilakkuma

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Challenges

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Goal

Input model

Output model

- +Head Proportion

- +Body-to-feet Proportion

- +Body-to-head Width Proportion

Body Proportions

- +Enlarge Scale

- +Stretch Scale

Signature Characteristics

optimization

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Related Work

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Mesh Deformation

Surface-based deformation techniques Alexa et al. 2003 Lipman et al. 2004 Sorkine et al. 2004 Zhou et al. 2005 Huang et al. 2006

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Mesh Deformation

Skeleton-based deformation techniques Linear-Blend Skinning (LBS)

Magenat-Thalmann et al. 1988 Lewis et al. 2000

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Geometry Processing

Mesh simplification Cigmoni et al. 1997 Garland et al. 1997 Lindstrom et al. 2000 Luebke et al. 2002

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Geometry Processing

Mesh smoothing Field et al. 1988 Shontz et al. 2003 Baker et al. 2004 Eigensatz et al. 2008

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Artistic Stylization

Deussen et al. 2000 Qu et al.

2008

Gal et al. 2007Rivers et al.

2010

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Our Method

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User Input: Body Proportion

Head proportion Body-to-feet proportion Body-to-head width proportion

- +- +- +

- +- +- +

- +- +- +

- +- +- +

Input model

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User Input: Signature Characteristics

Marking signature characteristics

- +Enlarge Scale

- +Enlarge Scale

Input model

- +Stretch Scale

- +Stretch Scale

Input model

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Skeleton

TemplateBaran et al. SIGGRAPH2007

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Overview

Optimization-based approach

Input model & skeleton Deformed skeleton

SkeletonDeformation

MeshDeformation

Output model

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Skeleton Deformation

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Skeleton Deformation

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Mesh Deformation

Body proportion constraint Signature characteristic constraint Primitive fitting constraint Detail smoothing constraint

Total energy and optimization

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Body Proportion

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Signature Characteristic

Emphasizing along Skeleton Axes

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Signature Characteristic

Emphasizing along Skeleton Orthogonal Directions

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Primitive Fitting

Fitting head to a sphere

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Primitive Fitting

Fitting limbs to a capsule shape

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Detail Smoothing

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Total Energy and Optimization

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Result

Input model

Different body proportion parameters

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Result

Input model

Different body proportion parameters

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Result

25273 vertices, 16.287 seconds

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Result

4712 vertices, 2.48 seconds

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Result

1480 vertices, 0.749 seconds

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Result

5000 vertices, 2.527 seconds

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Comparison

Input model Body-part uniformly scaling

Our methodArtist hand crafted

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User Study

47 users 12 input models

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User Study

How cute? 1(Negative) 5(Positive) Are the SD counterparts cuter than the

original model? Which head proportion is cuter?

Input model3.55423

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Limitation

Correctly embedded skeleton Self-intersections and vertex sampling density Texture

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Conclusion

Optimization-based technique Semi-automatically create a character model

with the SD style Customization

Parameters with body proportion Signature

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Future Work

Solving texture distortion Texture stylization

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Acknowledgments

We thank the anonymous reviewers for their thoughtful suggestions, and also thank Digimax and SolidWorks for providing high quality character models. We also thank Sei Imai for designing The cartoon character Hatsune Miku’s SD version. This research was supported in part by the National Science Council of Taiwan under grant NSC101-2221-E-002-200-MY2.

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SD Models: Super-Deformed Character ModelsLiang-Tsen Shen, Sheng-Jie Luo, Chun-Kai Huang, and Bing-Yu Chen

Thank you!Additional materials: http://www.cmlab.csie.ntu.edu.tw/~forestking/research/PG12-SDModel/