A fast orientation and skew detection algorithm for monochromatic document images

ABSTRACT

Very often in the digitization process, documents are either not placed with the correct orientation or are rotated of small angles in relation to the original image axis. These factors make more difficult the visualization of images by human users, increase the complexity of any sort of automatic image recognition, degrade the performance of OCR tools, increase the space needed for image storage, etc. This paper presents a fast algorithm for orientation and skew detection for complex monochromatic document images, which is capable of detecting any document rotation at a high precision.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.4 IMAGE PROCESSING AND COMPUTER VISION

Additional Classification:
  I. Computing Methodologies
  I.4 IMAGE PROCESSING AND COMPUTER VISION
      I.4.3 Enhancement
          Subjects: Filtering

General Terms:
Algorithms, Design, Experimentation

Keywords:
monochromatic document image, orientation and skew detection