Table Structure Extraction from Form Documents Based on Gradient-Wavelet Scheme

  • Dihua Xi
  • Seong-Whan Lee
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1655)


Based on gradient and wavelet analyses, a novel scheme has been developed to extract table structures from skewed form document images. In this scheme, first, a skewed form document image is rotated according to the angle obtained from the gradient algorithm. Then the deskewed image is decomposed into four sub-images by divisible Multiresolution Analysis(MRA) wavelets. Afterwards, the table structure image which represents the geometric structure of the form can be obtained from the sub-images by a modified wavelet reconstruction algorithm. Meanwhile, another document image without table lines can be produced by Minkowski operation and is referred to as a table free image. Experimental results indicate that this new scheme can be applied to process the skewed form document images with promising achievements.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Dihua Xi
    • 1
  • Seong-Whan Lee
    • 1
  1. 1.Center for Artificial Vision ResearchKorea UniversitySeongbuk-ku, SeoulKorea

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