1. A method for detecting distortion in an input image of a scanned book, the input image being one of a digitized image stored in a memory or a scanned image from a scanner, comprising: using a processor to divide the input image into a plurality of blocks of pixels; associate each block of pixels in the input image with a pixel in a feature image; analyze values of each pixel in the feature image to create a binary map of the feature image, wherein each pixel in the binary map corresponds to a page area or not a page area; subject the binary map to object segmentation to group binary map pixels corresponding to a page area; create a set of page objects; detect borders of the page area; and detect distortion within the page area; wherein two page objects are created and detecting distortion comprises: (a) in the feature image selectin a first column next to a left border the page area and track the values of background components of pixels in the first column from a center of a top page object to a middle of the two page objects; (b) checking whether the tracked values have a top-to-bottom decline that is greater than a minimum value, and when the top-to-bottom decline is greater than the minimum value identify the pixel location in the feature image where the to to-bottom decline starts in the first column, and when the top-to-bottom decline is not greater than the minimum value then return to (a) and select another column that is next to the first column; and mapping the pixel location in the feature image where the top-to-bottom decline starts in the first column to the input image to identify the coordinate of the top-left corner of a shadow distortion in the input image.