I have a few blu-ray discs that are a bit scratched. They play fine in my standalone player, but because of I/O errors, MakeMKV fails to back them up. I'd still like to get as good a backup copy of them as I can. From what I've read on the forum before, there isn't much interest in making MakeMKV more tolerant of read errors.
I had the idea of using ddrescue to get a "good as possible" ISO image, then (hopefully) using MakeMKV to decrypt it. On the disc I've been trying, after letting ddrescue run for a long time, the unreadable sectors add up to about 25MB (out of about 38GB), which doesn't seem too bad.
Now I want to use MakeMKV to decrypt the ISO. Of course it needs a VUK and/or VID. This is where my understanding gets foggy. Is there anything I can do to get one or other of those? Am I right that either of those will do? I couldn't find any pre-discovered VUKs for these discs. I've tried aacskeys, but the host key/certificate I have (from the aacskeys package in debian-multimedia) has been revoked by both my drives.
It seems that what I want *should* be possible just with MakeMKV. It can start the backup and decrypt most of the disc before it fails -- it's only the bad sectors that stop it working. If anyone has any suggestions about how to proceed, I'd be very grateful.