Word and Sentence Extraction Using Irregular Pyramid

  • Poh Kok Loo
  • Chew Lim Tan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2423)


This paper presents the result of our continued work on a further enhancement to our previous proposed algorithm. Moving beyond the extraction of word groups and based on the same irregular pyramid structure the new proposed algorithm groups the extracted words into sentences. The uniqueness of the algorithm is in its ability to process text of a wide variation in terms of size, font, orientation and layout on the same document image. No assumption is made on any specified document type. The algorithm is based on the irregular pyramid structure with the application of four fundamental concepts. The first is the inclusion of background information. The second is the concept of closeness where text information within a group is close to each other, in terms of spatial distance, as compared to other text areas. The third is the “majority win” strategy that is more suitable under the greatly varying environment than a constant threshold value. The final concept is the uniformity and continuity among words belonging to the same sentence.


Text Image Document Image Pyramid Structure Word Fragment Word Group 
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 2002

Authors and Affiliations

  • Poh Kok Loo
    • 1
  • Chew Lim Tan
    • 2
  1. 1.School of the Built Environment & DesignSingapore PolytechnicSingapore
  2. 2.School of ComputingNational University of SingaporeSingapore

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