Pattern skeletonization using run-length-wise processing for intersection distortion problem

Abstract Existing skeletonization methods are largely pixel-wise methods which present problems at line pattern intersection regions. Challenged by the problems, we have developed a run-length-wise method in vectorizing line pattern intersections and solving intersection distortion problem in skeletonization. We experimented the method with handwritten Chinese character and numeral character skeletonization to find points of convergence and divergence and to link them into meaningful sets of data. Using these sets of data we construct windows around intersection regions and replace distorted intersection with straight line intersection. Thus we overcome the distortion problem and at the same time retain the smooth property of pixel-wise thinning.

[1]  George S. Malindzak,et al.  An algorithm for line intersection identification , 1981, Pattern Recognit..

[2]  Ching Y. Suen,et al.  An alternate smoothing and stripping algorithm for thinning digital binary patterns , 1986 .

[3]  Theodosios Pavlidis,et al.  An asynchronous thinning algorithm , 1982, Comput. Graph. Image Process..

[4]  Azriel Rosenfeld,et al.  Some Parallel Thinning Algorithms for Digital Pictures , 1971, JACM.

[5]  Nabil Jean Naccache,et al.  SPTA: A proposed algorithm for thinning binary patterns , 1984, IEEE Transactions on Systems, Man, and Cybernetics.

[6]  Theo Pavlidis,et al.  A vectorizer and feature extractor for document recognition , 1986 .

[7]  Thomas Ottmann,et al.  Algorithms for Reporting and Counting Geometric Intersections , 1979, IEEE Transactions on Computers.

[8]  Patrick Shen-Pei Wang,et al.  A Fast and Flexible Thinning Algorithm , 1989, IEEE Trans. Computers.

[9]  Wen Xu,et al.  CGT: A fast thinning algorithm implemented on a sequential computer , 1987, IEEE Transactions on Systems, Man, and Cybernetics.

[10]  Lawrence O'Gorman,et al.  K × K Thinning , 1990, Comput. Vis. Graph. Image Process..

[11]  B. Ripley,et al.  Pattern Recognition , 1968, Nature.

[12]  Yung-Sheng Chen,et al.  A modified fast parallel algorithm for thinning digital patterns , 1988, Pattern Recognit. Lett..

[13]  Chin-Chuan Han,et al.  Skeleton generation of engineering drawings via contour matching , 1994, Pattern Recognit..

[14]  Zicheng Guo,et al.  Parallel thinning with two-subiteration algorithms , 1989, Commun. ACM.

[15]  Ching Y. Suen.  Thinning Methodologies for Pattern Recognition , 1994 .

[16]  Ching Y. Suen,et al.  A fast parallel algorithm for thinning digital patterns , 1984, CACM.

[17]  Javier Jiménez,et al.  Some experiments in image vectorization , 1982 .

[18]  KUO-CHIN FAN,et al.  Skeletonization of binary images with nonuniform width via block decomposition and contour vector matching , 1998, Pattern Recognit..

[19]  C. J. Hilditch,et al.  Linear Skeletons From Square Cupboards , 1969 .

[20]  Kuo-Chin Fan,et al.  Recognition of handwritten Chinese characters by modified relaxation methods , 1994, Image Vis. Comput..

[21]  Bei Li,et al.  A knowledge-based thinning algorithm , 1991, Pattern Recognit..

[22]  Edward S. Deutsch,et al.  Thinning algorithms on rectangular, hexagonal, and triangular arrays , 1972, Commun. ACM.

[23]  Ze-Nian Li,et al.  An X-Crossing Preserving Skeletonization Algorithm , 1993, Int. J. Pattern Recognit. Artif. Intell..

[24]  Michael Ian Shamos,et al.  Geometric intersection problems , 1976, 17th Annual Symposium on Foundations of Computer Science (sfcs 1976).

[25]  T. Pavlidis.  A thinning algorithm for discrete binary images , 1980 .

[26]  Jun S. Huang,et al.  Stroke segmentation by bernstein-bezier curve fitting , 1990, Pattern Recognit..

[27]  R. M. Brown,et al.  Handprinted symbol recognition system , 1988, Pattern Recognit..

[28]  Toshihiro Suzuki,et al.  Structural Description of Line Images by the Cross Section Sequence Graph , 1993, Int. J. Pattern Recognit. Artif. Intell..

[29]  J. Sklansky,et al.  Skeleton generation fromx, y boundary sequences , 1981 .

[30]  Hong Yan,et al.  Structural primitive extraction and coding for handwritten numeral recognition , 1998, Pattern Recognit..

[31]  Ruowei Zhou,et al.  A novel single-pass thinning algorithm and an effective set of performance criteria , 1995, Pattern Recognit. Lett..

[32]  Chungnan Lee,et al.  A Chinese-character-stroke-extraction algorithm based on contour information , 1998, Pattern Recognit..

[33]  Patrick Shen-Pei Wang,et al.  A New Parallel Thinning Methodology , 1994, Int. J. Pattern Recognit. Artif. Intell..