Paper Info
Title
Wavelet transform for skew angle detection in printed Persian documents
Abstract
When a document is fed to a scanner for digitization, it suffers from some degrees of skew. This skew has a detrimental effect on character recognition. In this paper we present two novel skew estimation methods for scanned Persian documents that estimates skew angles based on the wavelet decompositions and projection profile analysis. In the first algorithm, one row of the skewed document images is selected and is decomposed by the wavelet transform and in the second algorithm the whole document image is decomposed. Then, in both algorithms the matrix containing the absolute values of the horizontal sub-band coefficients, is then rotated through a range of angles. A projection profile is computed at each angle, and the angle that maximizes the maximum projection profile is regarded as the skew angle. The first algorithm is used for limited angle but second algorithm is used for wide angles.
Year
DOI
Venue
2011
10.1117/12.896301
Proceedings of SPIE
Keywords
Field
DocType
Document analysis,Skew detection and correction,Wavelet transform,Projection profile
Pattern recognition,Continuous wavelet transform,Discrete wavelet transform,Skew,Artificial intelligence,Cascade algorithm,Stationary wavelet transform,Wavelet packet decomposition,Mathematics,Wavelet,Wavelet transform
Conference
Volume
ISSN
Citations 
8009
0277-786X
0
PageRank 
References 
Authors
0.34
5
2
Name
Order
Citations
PageRank
samira nasrollahi dizajyekan100.68
Afshin Ebrahimi2195.76