Deskew is a 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.
Deskew is a tool for batch deskewing (auto-straightening) scanned text documents. Deskewing is a term used for fixing the scans to get the lines of text straight. That means rotating the image of the scanned page to compensate for the misalignment of the paper in the scanner.
Deskew uses Hough transform to detect “text lines” in the image and their orientation. As an output, you get an image rotated so that the detected lines are horizontal.
At the moment, Deskew is a command line tool for Windows, Linux, and Mac. As at November 2016, it is at version 1.20, with development still continuing. Source code is at Bitbucket as "App-Deskew". It is maintained by the developer, Marek Mauder.