Skew Angle Estimation and Correction for Noisy Document Images
- 1.3k Downloads
Document skew commonly occurs during document scanning; it should be avoided because it dramatically reduces the accuracy of the OCR. Noise removal is an important procedure before on going further processing. This paper describes an approach towards noise removal, skew detection and correction for text in scanned documents. Preprocessing is a stage, comprising number of adjustments in order to obtain the noise reduced results, and then the skew angle is estimated. Instead of deriving a skew angle from the text lines, the proposed method uses various types of visual content of image skews, and HDT algorithm is used to select the useful image region dynamically. A bootstrap estimator is finally employed to combine various cues on local image blocks. Once the skew angle is being estimated it has to be rotated in the opposite direction in order to correct the skew angle.
KeywordsBagging estimator Visual content Preprocessing
Unable to display preview. Download preview PDF.
- 2.Yuan, B., Lim, C.: Skew Estimation for Scanned Documents from Noises. Centre for Remote Imaging. Sensing and Processing Department of Computer Science, School of Computing National University of Singapore, Models Image Process. 41(6), 234–243 (2005)Google Scholar
- 3.Faisal, S.H., Daniel, K.V., Thomas, B.M.: Response to Projection Methods Require Black Border Removal. Pattern Recognition. Lett. 28(7), 155–162 (2009)Google Scholar
- 4.Gaofeng, M.G., Nanning, Z.A., Zhang, Y., Song, Y.: Circular Noises Removal from Scanned Document Images. Institute of Artificial Intelligence and Robotics, Xi’an Jiaotong University, China (2007)Google Scholar
- 7.Martin, Pattichis: Characterization of Scanning Noise and Quantization on Texture Feature Analysis. In: Computer, University of New Mexico, Albuquerque, vol. 25(7), pp. 10–22 (2004)Google Scholar
- 8.Mudit, A.L., David Dorman, D.C.: Clutter Noise Removal in Binary Document Images. In: 10th International Conference on Document Analysis and Recognition, Computer, vol. 25(7), pp. 110–212 (2009)Google Scholar
- 9.Sarfraz, M., Zidouri, A., Shahab, S.A.: Novel Approach for Skew Estimation of Document Images. In: OCR SystemGoogle Scholar