Abstract
This paper proposes a new approach to a method to estimate a skew angle of a rotated document image. This is realized by using Speeded-Up Robust Features (SURF), and the goal is that it enables the image to be rotated back to the correct orientation. SURF detects a number of keypoints both from the reference image on which a set of standard alphabets (e.g. letter eaf through ezf in a certain font) are written, and the image of the rotated document. Two nearest features each from the reference image and the input image are compared to decide to how many degrees the feature in the input image is rotated. Finally the skew angle of the whole input image( the global skew angle) is decided by the majority of the total votes of angles that have been calculated as mentioned above.
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© 2011 Springer-Verlag Berlin Heidelberg
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Shiraishi, S., Feng, Y., Uchida, S. (2011). A New Approach for Instance-Based Skew Estimation. In: König, A., Dengel, A., Hinkelmann, K., Kise, K., Howlett, R.J., Jain, L.C. (eds) Knowledge-Based and Intelligent Information and Engineering Systems. KES 2011. Lecture Notes in Computer Science(), vol 6884. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-23866-6_21
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DOI: https://doi.org/10.1007/978-3-642-23866-6_21
Publisher Name: Springer, Berlin, Heidelberg
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