一种改进的Bzier曲线细分算法  

Improved Subdivision and Refinement of Bézier Curves Algorithm

作　　者：狄效儒[1] 刘涛[1] 

机构地区：[1]西安科技大学计算机学院,陕西西安710054

出　　处：《微电子学与计算机》2009年第12期128-131,共4页Microelectronics & Computer

摘　　要：Bzier曲线(BC)在计算机辅助几何设计中有着广泛的应用.经典Bzier一个局限在于仅考虑了控制点CP的全局信息,因此BC和它的控制折线之间有很大的间距,导致形状表示中产生形状失真.文中提出一种改进的Bzier曲线细分和复合方法,该方法将原BC细分为两段,并将部分控制点向控制折线移动可变的距离,使细分后的Bzier曲线能够自由的靠近控制折线.由于合理选取新控制点列生成的函数,保证了新曲线具有CN-1连续性.在形状编码中只需要记录原Beizer控制点,再记录一个失真率μ,没有增加编码长度,因此该方法适合用于Bzier的形状表示.Bezier curves （BC） have been applied to a wide variety of computer- aided geometric design. A major limitation of the classical Bezier curve, is that only global information about its control points （CP） is considered, so there is a large gap between the curve and its control polygon, leading to distortion in shape representation. This paper presents a new method of subdivision and refinerment of Bezier Curves, which divide the origin BC into two segments, and move same of its CP towards the control polygon with a flexible parameter, therefore the divided curves can freely close to the control polygon. Because of choosing a appropriate dividing function, the new BC have C^N- 1 continuity. In the shape descriptor framework, Only the the origon CP and the rate-distortion is saved, without increasing： the number of CP. So this method can apply to the BC- based shape representation.

关 键 词：BEZIER曲线 曲线拟合 形状编码 图像处理 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]