Suppose you had your collection of DVDs which you lawfully bought in the marketplace.
Suppose you wanted to see them when you are running in the gym, on your iPad. You need to transcode them, i. e. make the conversion into another format (in my case .mp4).
Surprisingly, this simple problem is not that tractable, unless you commit money to some expensive proprietary software solution. The issue is the Content Scramble System, a lawful encryption system that scrambles the contents of the DVD and messes up the reading of them.
A simple transcoder – an utility that transitions a format into a different one – may fail if the encryption is not taken care of. And this is exactly what happens with a simple minded usage of the marvellous free & open source transcoder Handbrake
Handbrake needs the crucial library that inverts the scramble, libdvdcss.
Here is then the solution with respect to Handbrake 0.10.5.0 (64 bits) on Windows:
Download libdvdcss-2.dll from
http://download.videolan.org/libdvdcss/1.2.11/win32/libdvdcss-2.dll (32 bit version) or http://download.videolan.org/libdvdcss/1.2.11/win64/libdvdcss-2.dll (64 bit version).
Then, move the libdvdcss-2.dll into your Handbrake install directory (usually C:\Program Files\Handbrake\).