Entropy Based Skew Correction of Document Images

  • K. R. Arvind
  • Jayant Kumar
  • A. G. Ramakrishnan
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4815)

Abstract

The document images that are fed into an Optical Character Recognition system, might be skewed. This could be due to improper feeding of the document into the scanner or may be due to a faulty scanner. In this paper, we propose a skew detection and correction method for document images. We make use of the inherent randomness in the Horizontal Projection profiles of a text block image, as the skew of the image varies. The proposed algorithm has proved to be very robust and time efficient. The entire process takes less than a second on a 2.4 GHz Pentium IV PC.

Keywords

Document Image Block Image Horizontal Projection Text Block Entropy Calculation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. 1.
    Zhu, X., Yin, X.: A New Textual/Non- textual Classifier for Document Skew Correction. In: Proceedings of the 16th International Conference on Pattern Recognition (ICPR 2002) (2002)Google Scholar
  2. 2.
    Le, D.S., Thoma, G.R., Wechsler, H.: Automatic page orientation and skew angle detection or binary document images. Pattern Recognition 27Google Scholar
  3. 3.
    Avanindra, Chaudhuri, S.: Robust Detection of Skew in Document Images. IEEE Trans on Image Processing 6, 344–349 (1997)CrossRefGoogle Scholar
  4. 4.
    Avila, B.T., Lins, R.D.: A Fast Orientation and Skew Detection Algorithm for Monochromatic Document Images. In: Proceedings of the 2005 ACM symposium on Document engineering (2005)Google Scholar
  5. 5.
    Morita, M.E., Bortolozzi, F., Facon, J., Sabourin, R.: Morphological approach of handwritten word skew correction. In: Proceedings of International Symposium on Computer Graphics, Image Processing and Vision (SIBGRAPI 1998)Google Scholar
  6. 6.
    Arvind, K.R., Pati, P.B., Ramakrishnan, A.G.: Automatic text block seperation in document images. In: Proceedings of 4th International Conference on Intelligent Sensing and Information Processing (ICSIP 2006) (2006)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • K. R. Arvind
    • 1
  • Jayant Kumar
    • 1
  • A. G. Ramakrishnan
    • 1
  1. 1.MILE Lab, Electrical Engineering, Indian Institute of Science, Bangalore, 560012India

Personalised recommendations