So I was initially just trying to rip my Star Trek The Next Generation Bluray set for my media server (my personal taste is if I have the storage to do a fall disc backup to save the menus and extras (to me that's what separates DVDs and Blurays from VHS and HD-VHS), then I make make a compressed mkv from that for the media server (currently that is 30RF for blurays and 20RF for DVD, but I hope to improve my storage on my media server so I can set those lower later) with blurays I often assume they are newer and less like to have issues so I'm more likely to wait for doing full backups. However on season 1 disc 3 of my start trek TNG the stream 00000.mts (the episode Hide and Q) and 00035.mts (an extra feature not sure which) had some sort of error, both makemkv and manually copying them failed. At this point I wanted my full disc back up now! Which obviously failed on this disc even after cleaning. I checked and my local library had a copy, so I tried it and it failed as well. However oddly it only had an error with 00001.mts, it was a long shot however I wondered if I could combine these files to make a working decrypted full disc backup. Sure enough it worked! Here are the steps I did for anyone else who's OCD like me and might need this.
- I started making an encrypted backup of the more intact bluray (the library's copy)
- Then I stopped it when it started copying the streams and I manually copied all those over
- I then replaced the stream file that error-ed out part way through copying from the library copy, with the completely intact stream file from my personal copy (in this case it was stream 00001.mts not sure which episode it was)
- Theoretically at this point you can directly open the discet.dat file in the back up folder using makemkv, this never works for me on Debian 12 so instead I did as I always do and converted the folder to an ISO using genisoimage -iso-level 4 -allow-lowercase -l -udf -V "Volume Name" -o ISOname.iso BackupFolder then mounted it with gcdemu
- Then I ran a decryption full backup on the mounted ISO from makemkv, VLC is able to load this decrypted folder with the menus all episodes/features worked and I was even able to generate another decrypted iso in-case I want to burn a replacement in the future (that's the version of the backup I kept on my raid array)