A Method of the Post-Processing of Printed Formula Extraction

Abstract:

As an important step of printed formula recognition system, formula extraction locates the formula fields on the layout images of printed documents, which influences the performance of formula recognition to a great extent. However, the errors of automatic formula extraction occur inevitably because of the complexity of formulas themselves and the layouts which the formulas situated. To solve this problem, this paper designed a post-processing method to correct the errors existing in the results of formula extraction algorithm according to relative layout knowledge. First of all, the geometrical features of various layout fields were employed to correct the extraction errors. Then, the syntax rules were used to check the boundary components of different kinds of areas in layouts to identify which field it should belong to. Finally, the formula area was adjusted according to above mentioned information.

• Periodical: Applied Mechanics and Materials (Volumes 241-244)
• Pages: 2878-2881
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.241-244.2878
• Online since: December 2012
• Authors: Shi Ying Yu*, Yong Shang, Fang Yang, Xue Dong Tian
• Keywords: Error Correction, Geometrical Features, Post-Processing, Printed Formula Extraction, Syntax Features

References

[1] R. H. Anderson: Syntax-directed recognition of hand-printed two-dimensional mathematics, in: Interactive Systems for Experimental Applied Mathematics, Academic Press (1968).

DOI: 10.1016/b978-0-12-395608-8.50048-7

[2] K. F. Chan, D. B. Yeung: Mathematical expression recognition: a survey. International Journal on Document Analysis and Recognition, Vol. 3 (2000), p.3.

[3] A. Kacem, A. Belald: Automatic extraction of printed mathematical formulas using fuzzy logic and propagation of context, International Journal on Document Analysis and Recognition, Vol. 4 (2001), p.97.

DOI: 10.1007/s100320100064

[4] J. M. Jin, X. Han, Q. R. Wang: Mathematical formulas extraction. Proc. of the 7th International Conference on Document Analysis and Recognition, Scotland (2003), p.1138.

[5] R. Fatematn, T. Tokuyasu, B. Berman, et al.: Optical character recognition and parsing of typeset mathematics. Journal of Visual Communication and Image Representation, Vol. 7 (1996), p.2.

DOI: 10.1006/jvci.1996.0002

[6] H. J. Lee, J. S. Wang: Design of mathematical expression understanding system. Pattern Recognition Letters, Vol. 18 (1997), p.289.

[7] U. Garain, B. B. Chaudhuri, A. Ray Chaudhuri: Identification of embedded mathematical expressions in scanned documents. Proceedings of the 17th International Conference on Pattern Recognition, University of Cambridge, UK, Vol. 1-01 (2004), p.384.

DOI: 10.1109/icpr.2004.1334132

[8] K. Inoue R. Miyazaki, M. Suzuki: Optical recognition of printed mathematical documents. Proc. of the 3rd Asian Technology Conference in Mathematics, Tsukuba, Japan (1998) p.280.

[9] Z. W. Zhang, F. R. Kong, W. L. Liu, et al.: Extraction of mathematical expressions in printed Chinese technical documents. Journal of Chinese Information Processing, Vol. 12 (2007), p.86.

[10] Y. S. Guo, N. T. Tan, L. Huang, et al.: An identification method for mathematical expressions in scanned Chinese document. Journal of Chinese Information Processing, Vol. 22 (2008), p.83.