Vladan Vučković, Boban Arizanovic

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In this paper, as a pre-processing part of character segmentation system, an automatic document skew correction approach, based on Hough transform, is presented. Document skew is a common pre-processing problem and diverse approaches have been proposed in the past. The importance of solving this problem lies in the fact that further character segmentation process is impossible if document image is skewed. The character segmentation algorithm extended with skew correction algorithm has been proved to be efficient since the experimental results showed that successful character segmentation percentage is higher than 85 after the skew correction. Character segmentation algorithm results for skewed and de-skewed documents are also provided using the original Nikola Tesla’s documents from the “Nikola Tesla Museum”.


Skew correction, Hough transform, character segmentation, spatial transformations, rotation, fast algorithm

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