I have a collection of DVDs and CDs that I’ve been meaning to archive. However, most of them must be scratched because whenever I try to read them, they get an I/O error in a random spot of one of the 1gb files. I heard that you can do some magic with ddrescue and possibly even read them in reverse, but don’t know the limitations of that when it comes to USB DVD readers. How can I copy these reliably?