Deskew is described as 'tool for auto-straightening or deskewing scanned text documents. Deskew detects the orientation of text lines in the image. It rotates the image so the detected lines are horizontal. It is a command line tool for Windows, Linux, and Mac' and is an app in the Photos & Graphics category. There are five alternatives to Deskew for a variety of platforms, including Windows, Linux, iPhone, BSD and iPad. The best alternative is ScanTailor Advanced, which is both free and Open Source. Other great apps like Deskew are ScanTailor Advanced (Free, Open Source), YASW (Yet Another Scan Wizard) (Free, Open Source), DocScan (Free) and Book Scan Wizard (Free, Open Source).
Scan Tailor is an interactive post-processing tool for scanned pages. It performs operations such as page splitting, deskewing, adding/removing borders, and others. You give it raw scans, and you get pages ready to be printed or assembled into a PDF or DJVU file.
Download YASW for free. Yet Another Scan Wizard. YASW (Yet Another Scan Wizard) is an application used to correct images taken with a camera or scanner. It can be used to post process the scanning of a book.
A utility to help with Book scanning using cameras as a scanner. It will automate things such as cropping, rotating, fixing keystoning, fixing the DPI, and outputing it to tiff files that can be changed into PDF's or ebooks.