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)


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.


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.


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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

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