Please wait a minute...
Front. Inform. Technol. Electron. Eng.  2014, Vol. 15 Issue (12): 1098-1105    DOI: 10.1631/jzus.C1400076
    
UE样条曲线的升阶
Xiao-juan Duan, Guo-zhao Wang
Department of Mathematics, Zhejiang University, Hangzhou 310027, China
Degree elevation of unified and extended spline curves
Xiao-juan Duan, Guo-zhao Wang
Department of Mathematics, Zhejiang University, Hangzhou 310027, China
 全文: PDF 
摘要: 针对UE样条悬而未决的升阶问题,给出UE样条的升阶方法,并揭示此方法的几何意义。引入一种新的样条基函数-双阶UE样条基函数。在原始节点向量中逐个插入互异节点,将UE样条函数按区间逐段升阶,最终使UE样条在整个定义域内达到升阶效果,并给出这种升阶方法的几何意义。由于曲线在节点处的连续性保持不变,低阶的UE样条曲线可由高阶UE样条曲线表示。首先,引入一种新的样条基函数-双阶UE样条基函数。这种样条基在整个节点区间有两种阶数。其中,前一段节点区间的次数比后一段节点区间的次数高1次(图1)。然后,通过往节点向量中插入节点,双阶UE样条基的某特定区间次数升高1次,从而得到双阶UE样条在节点插入前后的基函数关系(图2)继而得到节点插入前后双阶UE样条函数控制顶点之间的关系。通过逐个插入互异节点,可使UE样条逐段升阶。最后,根据节点插入前后的新旧控制顶点关系,证明UE样条的升阶可以理解为其控制多边形的割角过程(图3、4)。通过在节点向量中逐个插入互异节点,解决了UE样条的升阶问题,并证明了UE样条的升阶可以解释为其控制多边形的割角过程。
关键词: 升阶UE样条双阶UE样条割角几何解释    
Abstract: Unified and extended splines (UE-splines), which unify and extend polynomial, trigonometric, and hyperbolic B-splines, inherit most properties of B-splines and have some advantages over B-splines. The interest of this paper is the degree elevation algorithm of UE-spline curves and its geometric meaning. Our main idea is to elevate the degree of UE-spline curves one knot interval by one knot interval. First, we construct a new class of basis functions, called bi-order UE-spline basis functions which are defined by the integral definition of splines. Then some important properties of bi-order UE-splines are given, especially for the transformation formulae of the basis functions before and after inserting a knot into the knot vector. Finally, we prove that the degree elevation of UE-spline curves can be interpreted as a process of corner cutting on the control polygons, just as in the manner of B-splines. This degree elevation algorithm possesses strong geometric intuition.
Key words: Degree elevation    Unified and extended splines (UE-splines)    Bi-order UE-splines    Corner cutting    Geometric explanation
收稿日期: 2014-03-06 出版日期: 2014-12-05
CLC:  TP391.7  
服务  
把本文推荐给朋友
加入引用管理器
E-mail Alert
RSS
作者相关文章  
Xiao-juan Duan
Guo-zhao Wang

引用本文:

Xiao-juan Duan, Guo-zhao Wang. Degree elevation of unified and extended spline curves. Front. Inform. Technol. Electron. Eng., 2014, 15(12): 1098-1105.

链接本文:

http://www.zjujournals.com/xueshu/fitee/CN/10.1631/jzus.C1400076        http://www.zjujournals.com/xueshu/fitee/CN/Y2014/V15/I12/1098

[1] Yan-hong Liu, Juan Cao, Zhong-gui Chen, Xiao-ming Zeng. 射线与三角Bézier曲面交点的混合裁剪算法[J]. Front. Inform. Technol. Electron. Eng., 2016, 17(10): 1018-1030.
[2] . Image meshing via hierarchical optimization[J]. Front. Inform. Technol. Electron. Eng., 2016, 17(1): 32-40.
[3] Xiao Liu, Jia-min Liu, An-xi Cao, Zhuang-le Yao. 一种新型三维不规则排样构造算法HAPE3D[J]. Front. Inform. Technol. Electron. Eng., 2015, 16(5): 380-390.
[4] Divya Udayan J, HyungSeok Kim, Jee-In Kim. 基于3D空间组件提取和排列的古建筑重建图像方法[J]. Front. Inform. Technol. Electron. Eng., 2015, 16(1): 12-27.
[5] Yong-wei Miao, Fei-xia Hu, Min-yan Chen, Zhen Liu, Hua-hao Shou. 视觉显著性引导的特征敏感形状简化[J]. Front. Inform. Technol. Electron. Eng., 2014, 15(9): 744-753.
[6] Fei-wei Qin, Lu-ye Li, Shu-ming Gao, Xiao-ling Yang, Xiang Chen. 用于三维CAD模型分类的深度学习方法[J]. Front. Inform. Technol. Electron. Eng., 2014, 15(2): 91-106.
[7] Lie-fu Ai, Jun-qing Yu, Yun-feng He, Tao Guan. High-dimensional indexing technologies for large scale content-based image retrieval: a review[J]. Front. Inform. Technol. Electron. Eng., 2013, 14(7): 505-520.
[8] Xiao-hong Tan, Rui-min Shen, Yan Wang. Personalized course generation and evolution based on genetic algorithms[J]. Front. Inform. Technol. Electron. Eng., 2012, 13(12): 909-917.
[9] Shi-yan Wang, Hui-min Yu. Convex relaxation for a 3D spatiotemporal segmentation model using the primal-dual method[J]. Front. Inform. Technol. Electron. Eng., 2012, 13(6): 428-439.
[10] Juan Cao, Guo-zhao Wang. Non-uniform B-spline curves with multiple shape parameters[J]. Front. Inform. Technol. Electron. Eng., 2011, 12(10): 800-808.
[11] Yu-lei Geng, Jin Wang, Guo-dong Lu, Zheng Liu, Gang Chen. Sketch based garment modeling on an arbitrary view of a 3D virtual human model[J]. Front. Inform. Technol. Electron. Eng., 2011, 12(3): 195-203.
[12] Chun-luan Zhou, Jun Xiao. Cartoon capture by key-frame based contour tracking[J]. Front. Inform. Technol. Electron. Eng., 2011, 12(1): 36-43.
[13] Jia Li, Han-nan Yu, Yong-hong Tian, Tie-jun Huang, Wen Gao. [J]. Frontiers of Information Technology & Electronic Engineering, 2010, 11(11): 850-859.
[14] Wan-qiang Shen, Guo-zhao Wang. Triangular domain extension of linear Bernstein-like trigonometric polynomial basis[J]. Front. Inform. Technol. Electron. Eng., 2010, 11(5): 356-364.
[15] Qian-qian Hu, Guo-jin Wang. Representing conics by low degree rational DP curves[J]. Front. Inform. Technol. Electron. Eng., 2010, 11(4): 278-289.