Which free software can I use to deskew scanned images
I have several PDFs made up of book pages' scans. The scans are made from two pages at a time and some of these scans are skewed, making text appear slightly tilted.
I'm looking for a tool that could allow me to do an automatic optimization by deskewing the scans without losing readability. I've found the GPL software briss to crop the scans in order to have a 1:1 page ratio instead of 2:1, but I don't have any tool to deskew the pages.
I stumbled upon unpaper, another open source tool that seems perfect for what I want to do, but that tool is Linux only and it doesn't work on PDF files directly.
Any hint is appreciated.