Hujun Bao

Professor, Computer Graphics Group

Address: State Key Lab of CAD&CG, Zhejiang University,

Hangzhou, 310027, China

Phone:   +86-571-87951045

Fax:     +86-571-87951780

Email:   bao@cad.zju.edu.cn

Web:     http://www.cad.zju.edu.cn/home/bao

I received my Bachelor Degree in 1987 and Ph. D degree in 1993, both from applied mathematics of Zhejiang University. In August 1993, I joined State Key Lab of CAD&CG, Zhejiang University.

  Realistic Image Synthesis (1991~1997)

My researches on realistic image synthesis mainly focus on extended shading models and fast rendering algorithms. Based on a unified shading model, three analytical shading models for linear, curve and polygonal light sources are proposed to calculate local surface intensity. These shading models are further incorporated in our fast ray tracing algorithm with space subdivision scheme and radiosity algorithm for planar scenes. We also developed radiosity algorithms for general scenes with curved surfaces using finite element technique.

  Realtime Rendering Technique (1997~present)

Visibility determination is a key problem to realtime rendering complex scenes. To improve the interaction rates of large size of scenes, the potential visible set (PVS) and visibility simplification technique are combined to reduce the visibility complexity of scenes in each cell at preprocessing phase. By dynamically simplifying the scene into a set of range images, we design a distributed realtime walkthrough system, in which an image warping algorithm and a camera predictor are developed to synthesize the image of any view. Note that PVSs are expensive to store and load, a more compact representation, called global occlusion map (GOM), is designed for our realtime rendering system. The global visibility sampling theory indicates a conservative sampling rate for a view cell and how to sample the cell to acquire the visibility information. Lately, we also devise point and polygon based hybrid rendering algorithms for realtime rendering complex scenes.

  Digital Geometry Processing (1998~present)

3D geometry is becoming a new type of medium after sound, images and video. Digital geometry processing is still a challenging problem in computer graphics since it is difficult to process the surface attributes of meshes in a unified way. By introducing barycentric constraints into the multiresolution Laplacian relaxation process, a constrained mesh fairing algorithm is proposed for smoothing complex meshes. The volume preserved mesh smoothing algorithm can achieve better results. The 3D morphing algorithm can perform shape transformation between two closed polyhedra with the same genus using local parameterization technique. The algorithm is further extended using variational interpolation to handle arbitrary polyhedra. Recently, a unified processing framework is proposed for digital signal processing over arbitrary meshes. Within this framework, all surface attributes can be processed in a unified way. A geometric signal processing toolkit is designed for many applications. In the toolkit, many geometry operations, such as filtering, enhancement, convolution, editing, compression, watermarking, texture mapping etc., are included.

  Field-based Surface Modeling (1999~present)

To create models with complex shapes quickly is a hard task in computer graphics. Compared to parameter representation, implicit representation has many advantages in modeling complex shapes. Based on geometric constraints, cubic algebraic curves can be easily constructed like parametric curves. The continuous scalar field based freeform modeling technique provides users a method to conveniently construct complex models with polyhedral skeletons. The contour based modeling algorithm represents the object from a sequence of images in a distance field, from which the object can be extracted.

Kun Zhou, Hujun Bao, Jiaoying Shi, Qunsheng Peng

Framework for Digital Signal Processing Over Arbitrary Meshes

Submission

(Abstract)  (Acrobat, 35 MB)

 

 

Kun Zhou, Hujun Bao, Xinguo Liu et al.

Geometric Signal Compression

Submission

(Abstract)  (Acrobat, 34 MB)

 

 

Wei Hua, Hujun Bao, Qunsheng Peng

Global Visibility Sampling

Submission

(Abstract)  (Acrobat, 2.29 MB)

 

 

Zhongding Jiang, Hujun Bao, LiZhuang Ma

Synthesizing High Resolution Images from Real Video

Submission

(Abstract)  (Acrobat, 1.91 MB)

 

 

Xingguo Liu, Hujun Bao, Harry Shum, Qunsheng Peng

Volume Constrained Smoothing Method for Meshes

Accepted by Graphical Models.

(Abstract)  (Acrobat, 2.89 MB)

 

Ying Tang, Jin Wang, Hujun Bao, Qunsheng Peng

RBF-based Texture Mapping

Accepted by Computers & Graphics

(Abstract)  (Acrobat, 2.2 MB)

 

Xiang Fang, Hujun Bao, PhengAnn Heng, et al.

Continuous Field Based Free-Form Surface Modeling and Morphing

Computers & Graphics, 2001, 25(3)

(Abstract)  (Acrobat, 439 KB)

 

Wei Hua, Hujun Bao, Qunsheng Peng

Hierarchical Surface Fragments

Accepted by Progress in Natural Science.

 

Jin Wang, Hujun Bao, Weihua Zhou, Qunsheng Peng, Yingqing Xu

Automatic Image-Based Pencil Sketch Rendering

Journal of Computer Science & Technology, Vol.17, No.3, 2002

 

Jinhui Chen, Sanyuan Zhang, Hujun Bao, Qunsheng Peng

G3 Continouous Curve Modeling with Rational Cubic Bezier Spline

Progress in Natural Science, No.3, 2002

 

Lanfang Miao, Xinguo Liu, Qunsheng Peng, Hujun Bao

BRDC: Binary Representation of Displacement Code for Line

Computers & Graphics, No.3, 2002

 

Sanyuan Zhang, Hujun Bao, Baogang Wei

Cubic Algebraic Curve Based on Geometric Constraints

Computer Aided Geometric Design, 2001, 18:299-307  

 

Xingguo Liu, Hujun BaoPhengAnn Henget al.

Constrained Multiresolution Fairing for Meshes

Computer Graphics Forum, 2001, 20(2)

(Abstract)  (Acrobat,35M)

 

Xingguo Liu, Hujun Bao,Qunsheng Peng

Noise Removal Algorithm for Polygonal Meshes

Progress in Natural Science, 10(10), 2000

 

Hanqiu SunHujun Bao

Interactive texture mapping for polygonal models

International Journal of Computational Geometry, 15(1-3):41-49, 2000

 

Hujun Bao, Li Chen, Jianguo Ying, Qunsheng Peng

Non-linear View interpolation

IEEE Journal of Visualization and Computer Animation, 1999, 10(4):233-241

 

Wenting Zheng, Hujun Bao, Qunsheng Peng, Hanqiu Sun

Distributed Virtual Reality System Based on Hybrid Rendering

Progress in Natural Science, 10(3):218-224, 2000

 

Wenting Zheng, Hujun Bao, Qunsheng Peng, Hanqiu Sun

Realtime rendering algorithm Based on A Hybrid Rendering Scheme

Progress in Natural Science, 10(2):141-146, 2000

 

Yigang WangHujun BaoQunsheng Peng

Accelerated Walkthroughs of Virtual Environments Based on Visibility Preprocessing and Simplification

Computer Graphics Forum, 1998, 17(3): 187-194

 

Hujun BaoQunsheng Peng

Interactive 3D Morphing

Computer Graphics Forum, 1998, 17(3):23-30

 

Hujun BaoXiaogang Jin, Qunsheng Peng

A Progressive Radiosity Algorithm Based on Piecewise Polynomial Intensity Distribution, Computers & Graphics, 1997, 21(3):281-288

 

Hujun Bao, Sheng Fu, Qunsheng Peng

Accelerated Walkthroughs of Complex Scenes Based on Visibility Culling and Image-Based Rendering

Journal of Computer Science & Technology, 1998, 13 (Suppl.):9-16

 

Sheng Fu, Hujun Bao, Qunsheng Peng

An Accelerated Rendering Algorithm for Stereoscopic Display

Computers & Graphics, 1996,20(2):223-229

 

Hujun Bao, Jianguo Ying, Qunsheng Peng

Shading with Curve Light Sources

Computer Graphics Forum, 1995,14(3):217-227

 

Hujun Bao, Qunsheng Peng

A Fast Ray Tracing Algorithm Based on Adaptive Space Subdivision

Science in China(Series A),1995, 38(4):490-498

 

Hujun Bao, Qunsheng Peng

An Efficient Form-factor Evaluation Algorithm for Environments with Curved Surfaces

Computers & Graphics,1994,18(4):481-486

Hujun Bao, Qunsheng Peng

Shading Models for Linear and Area Light Sources

Computers & Graphics,1993,17(2):137-145

 

Hujun Bao, Qunsheng Peng

A Progressive Radiosity Algorithm for Scenes Containing Curved Surfaces

Computer Graphics Forum,1993,12(3):399-408

 

Mingfu Wang, Hujun Bao, Qunsheng Peng

A New Progressive Radiosity Algorithm Through the Use of Accurate Form-factors

Computers & Graphics,1992.9,16(3):303-309

 

3D Morphing

      Morphing of Bunny Model with Constraints, 213 KB

      Morphing of Head Model without Constraints, 157 KB

      Morphing of Head Model with Constraints, 158 KB

Animation

      Expression Clone from Video, 62 MB 

      Central Zone of Our New Campus, 44 MB

Non-Photorealistic Rendering

      Art Style Transfer Example 1, 954 KB

      Art Style Transfer Example 2, 1.17 MB

      Sketch from Image, 1.78 MB

Realtime Rendering of Large Size of Scenes

      Virtual City with 1,600,000 Polygons, 271 KB

      Point-Based Rendering Examples, 356 KB

      Point and Polygon Based Hybrid Rendering Scenes,

Realistic Image Synthesis

      Constraint-Based Texture Mapping, 841 KB

      Linear Light Source Shading Example, 

Digital Geometric Signal Processing

      Position Signal Filtering and Enhancement (Venus 2.70 MB, Horse 533 KB)

      Color Signal Filtering and Enhancement (Bunny 1.14 MB)

      Geometry Convolution (Bunny 1.38 MB, Mannequin 1.41 MB)

      Spectral Editing (Cat 1.11 MB)

      Geometric Signal Compression, 1.31 MB

PhD Students Advised

     Yigang Wang, Postdoctor, GMD, Germany

     Weiqun Cao,  Postdoctor, GMD, Germany

     Wenting Zheng, State Key Lab of CAD&CG, Zhejiang University

     Xinguo Liu, Microsoft Research China, Beijing

     Xiang Fang, Bell Laboratory, Shanghai

PhD students

     Qing Wang, Xiangjun Zhao, Ying Tang, Xun Wang, Huasheng Zhang, Hua Liu, Zhenlong Du

Master Students

     Yuan Wu, Mingya Dai, Dong Xu, Zanxian He, Hua Wang, Zhi He, Yunzhi Zhu, Hongwei Shan