Issue No. 02 - February (1997 vol. 19)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/34.574803
<p><b>Abstract</b>—Skew angle detection of scanned documents containing most popular Indian scripts (<it>Devnagari and Bangla</it>) is considered. Most characters in these scripts have horizontal lines at the top, called <it>head lines</it>. The character head lines mostly join one another in a word and the word appears as a single component. In the proposed method the components are at first labeled. The <it>upper envelope</it> of a component is found by columnwise scanning from an imaginary line above the component. Portions of upper envelope satisfying the properties of <it>digital straight line</it> are detected. They are clustered as belonging to single text lines. Estimates from individual clusters are combined to get the skew angle. Apart from accuracy and efficiency, an advantage of the method is that character segmentation and zone detection can be readily done from head line information, which is useful in Optical Character Recognition approaches of these scripts.</p>
Document processing, skew detection, optical character recognition (OCR), document structure analysis, digital library.
U. Pal and B. Chaudhuri, "Skew Angle Detection of Digitized Indian Script Documents," in IEEE Transactions on Pattern Analysis & Machine Intelligence, vol. 19, no. , pp. 182-186, 1997.