1. A document skew detection method, comprising: binarizing a document to provide a binarized document, performing a connected component analysis to remove noise and non-text elements from the binarized document; then splitting the binarized document into a first segment and a second segment, estimating a coarse skew angle for the first and second segments by performing a first pixel projection to determine a coarse Arabic horizontal line based on a maximum concentration of pixels in the pixel projection of a sharp writing line of Arabic script of the binarized document, and, estimating a fine skew angle within the coarse skew angle for the first and second segments by performing a second pixel projection to determine a fine Arabic horizontal line based on a maximum concentration of pixels in the pixel projection of the sharp writing line of Arabic script of the binarized document, and averaging the fine skew angle for the first and the second segments to determine a final skew angle.