Skew detection is one of the important part of any document image processing or character recognition system. The successful skew detection and correction may leads to success of document image processing or character recognition system. The skew is may be of scanned document image or of handwritten data. This paper gives the survey of various skew detection techniques used for Devanagari script as well as other scripts. The methods which are used mostly for skew detection like Hough transform, Fourier transform, projection profile, principle component analysis, nearest-neighbor clustering and cross-correlation are described in this paper.

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Devanagari Script Pre-processing Skew Detection Skew Correction