A generic shape descriptor using Bezier curves

Bezier curves are robust tool for a wide array of applications ranging from computer-aided design to calligraphic character, outlining and object shape description. In terms of the control point generation process, existing shape descriptor techniques that employ Bezier curves do not distinguish between regions where an object's shape changes rapidly and those where the change is more gradual or flat. This can lead to an erroneous shape description, particularly where there are significantly sharp changes in shape, such as at sharp corners. This paper presents a novel shape description algorithm called a generic shape descriptor using Bezier curves (SDBC), which defines a new strategy for Bezier control point generation by integrating domain specific information about the shape of an object in a particular region. The strategy also includes an improved dynamic fixed length coding scheme for control points. The SDBC framework has been rigorously tested upon a number of arbitrary shapes, and both quantitative and qualitative analyses have confirmed its superior performance in comparison with existing algorithms.

[1]  Herbert Freeman,et al.  On the Encoding of Arbitrary Geometric Configurations , 1961, IRE Trans. Electron. Comput..

[2]  Hsi-Jian Lee,et al.  A Bezier curve-based approach to shape description for Chinese calligraphy characters , 2001, Proceedings of Sixth International Conference on Document Analysis and Recognition.

[3]  J.J.S.P. Cabral,et al.  An introduction to splines for use in computer graphics & geometric modeling: Richard H. Bartels, John C. Beatty & Brian A. Barsky, Morgan Kaufmann Publishers, Inc., Los Altos, California, 1987 , 1992 .

[4]  Luigi Cinque,et al.  Shape description using cubic polynomial Bezier curves , 1998, Pattern Recognit. Lett..

[5]  Fernando Pereira,et al.  Spatial shape error concealment for object-based image and video coding , 2004, IEEE Transactions on Image Processing.

[6]  Plerre Bézier Emploi des machines a commande numérique , 1970 .

[7]  Aggelos K. Katsaggelos,et al.  Rate-Distortion Based Video Compression: Optimal Video Frame Compression and Object Boundary Encoding , 1996 .

[8]  B. Barsky,et al.  An Introduction to Splines for Use in Computer Graphics and Geometric Modeling , 1987 .

[9]  Laurence S. Dooley,et al.  A modified distortion measurement algorithm for shape coding , 2004 .

[10]  Muhammad Sarfraz,et al.  Automatic outline capture of Arabic fonts , 2002, Inf. Sci..

[11]  Paul Douglas,et al.  Proceedings International Conference on Information Technology: Coding and Computing , 2002, Proceedings. International Conference on Information Technology: Coding and Computing.

[12]  Guojin Wang,et al.  Some estimates of the height of rational Bernstein-Bezier triangular surfaces , 2004, Geometric Modeling and Processing, 2004. Proceedings.

[13]  Aggelos K. Katsaggelos,et al.  Rate-Distortion Based Video Compression , 1997, Springer US.

[14]  Paul Dierckx,et al.  Curve and surface fitting with splines , 1994, Monographs on numerical analysis.