some questions on how MakeMKV works
Posted: Sat Oct 21, 2023 10:17 pm
Hey.
I recently bought a LibreFriendly device (Pioneer BDR-XS07TUHD, FW 1.02) from @asmcom in order to play&backup my UHD BluRays on Linux.
I've been used to being able to play normal (non-UHD) BluRays directly under Linux (e.g. with mpv) as long as the key was already present in the well-known KEYDB.cfg, with libaacs doing the magic to decrypt the files on the fly).
Now I tried the same with that Pioneer device and a UHD, for which the key was already present in KEYDB.cfg (checked it via the SHA1 of that one file) but that failed.
At first I thought it might be some Linux/mpv issue, but I guess now it wasn't.
When I had tested this, I had my LibreFriendly device connected to my Linux, mounted the UHD BD and simply tried to play back via mpv bd:// .... As said, that didn't work.
Subsequently I backuped&decrypted the UHD BD on Windows using MakeMKV (the drive attached to the host running the Windows). That did work.
And when I sshfs-mounted the backuped&decrypted BluRay directory tree on my Linux, I could also play it via mpv (with and without KEYDB.cfg being present).
No I tried the following:
Attached the LibreFriendly device to the running Windows, inserted the UHD BD, started the MakeMKV programm (but didn't start any backup or conversion process), sshfs-mounted the Bluray drive to my Linux, started playback and... it worked (but only when the KEYDB.cfg was present - as expected).
So question:
1) I'd now assume, that having the key in KEYDB.cfg alone is not enough and even the LibreFrienly drive would return some garbage data (and not the real encrypted data) when reading the files from the BD.
And MakeMKV somehow patches the drive firmware (while MakeMKV) is running, then the drive gives me the right (but still encrypted) data,... but now my mpv/libaacs can decrypt it, given they have the key in KEYDB.cfg.
Does that sound right?
2) So if I want to backup *everything*... all I need to do is copy all files *as is* .... but while MakeMKV is running to have the firmware "improved". And as long as I have the key, I can later on use any tool that supports libaacs to play/convert/etc.?
This, AFAIU, is what MakeMKV does, when it makes a backup and the ckeckbox for decrypt is disabled - simply copying all files, right?
3) Alternatively I could also make a backup were the files are already decrypted (this, AFAIU, is what MakeMKV's backup does when the checkbox for decrypt is enabled, right)?
Would that also give me *everything* on the BD (i.e. no quality loss or re-encoding)... just with the difference that the files are already all decrypted?
Or would that cause already some further modifications (like to meta-data, menus, etc.)?
Just out of curiosity, when I have copied the raw/encrypted files, while MakeMKV was running and the device was in LibreMode... are there any OpenSource tools to decrypt the (copied but still encrypted) Bluray structure?
4) Actually making an MKV file (with MakeMKV).
AFAIU, this is not really needed for the purpose of archiving, is it?
As soon as I have copied all files (while the drive was actually in LibreFriendly mode, because MakeMKV was running) and either I have decrypted the files with MakeMKV or have the key in KEYDB.cfg (and the files not decrypted) ... I'm fine - even if MakeMKV would cease to exist or all my LibreDrives became unusable.
Right?
Last but not least...
5) If it's indeed as I presume, that the drive gives garbage data (and not even the encrypted data) when it's not truly in LibreFriendly mode (because MakeMKV is not running)... why does this seem to only happen with UHD? I could just perfectly fine play back non UHD-BDs, without MakeMKV running.
I mean the kernel did not even show any drive errors, but apparently the drive just returned bogus data without even telling (how cheeky).
Did that change from non-UHD to UHD BluRay?
Thanks,
Jemima
I recently bought a LibreFriendly device (Pioneer BDR-XS07TUHD, FW 1.02) from @asmcom in order to play&backup my UHD BluRays on Linux.
I've been used to being able to play normal (non-UHD) BluRays directly under Linux (e.g. with mpv) as long as the key was already present in the well-known KEYDB.cfg, with libaacs doing the magic to decrypt the files on the fly).
Now I tried the same with that Pioneer device and a UHD, for which the key was already present in KEYDB.cfg (checked it via the SHA1 of that one file) but that failed.
At first I thought it might be some Linux/mpv issue, but I guess now it wasn't.
When I had tested this, I had my LibreFriendly device connected to my Linux, mounted the UHD BD and simply tried to play back via mpv bd:// .... As said, that didn't work.
Subsequently I backuped&decrypted the UHD BD on Windows using MakeMKV (the drive attached to the host running the Windows). That did work.
And when I sshfs-mounted the backuped&decrypted BluRay directory tree on my Linux, I could also play it via mpv (with and without KEYDB.cfg being present).
No I tried the following:
Attached the LibreFriendly device to the running Windows, inserted the UHD BD, started the MakeMKV programm (but didn't start any backup or conversion process), sshfs-mounted the Bluray drive to my Linux, started playback and... it worked (but only when the KEYDB.cfg was present - as expected).
So question:
1) I'd now assume, that having the key in KEYDB.cfg alone is not enough and even the LibreFrienly drive would return some garbage data (and not the real encrypted data) when reading the files from the BD.
And MakeMKV somehow patches the drive firmware (while MakeMKV) is running, then the drive gives me the right (but still encrypted) data,... but now my mpv/libaacs can decrypt it, given they have the key in KEYDB.cfg.
Does that sound right?
2) So if I want to backup *everything*... all I need to do is copy all files *as is* .... but while MakeMKV is running to have the firmware "improved". And as long as I have the key, I can later on use any tool that supports libaacs to play/convert/etc.?
This, AFAIU, is what MakeMKV does, when it makes a backup and the ckeckbox for decrypt is disabled - simply copying all files, right?
3) Alternatively I could also make a backup were the files are already decrypted (this, AFAIU, is what MakeMKV's backup does when the checkbox for decrypt is enabled, right)?
Would that also give me *everything* on the BD (i.e. no quality loss or re-encoding)... just with the difference that the files are already all decrypted?
Or would that cause already some further modifications (like to meta-data, menus, etc.)?
Just out of curiosity, when I have copied the raw/encrypted files, while MakeMKV was running and the device was in LibreMode... are there any OpenSource tools to decrypt the (copied but still encrypted) Bluray structure?
4) Actually making an MKV file (with MakeMKV).
AFAIU, this is not really needed for the purpose of archiving, is it?
As soon as I have copied all files (while the drive was actually in LibreFriendly mode, because MakeMKV was running) and either I have decrypted the files with MakeMKV or have the key in KEYDB.cfg (and the files not decrypted) ... I'm fine - even if MakeMKV would cease to exist or all my LibreDrives became unusable.
Right?
Last but not least...
5) If it's indeed as I presume, that the drive gives garbage data (and not even the encrypted data) when it's not truly in LibreFriendly mode (because MakeMKV is not running)... why does this seem to only happen with UHD? I could just perfectly fine play back non UHD-BDs, without MakeMKV running.
I mean the kernel did not even show any drive errors, but apparently the drive just returned bogus data without even telling (how cheeky).
Did that change from non-UHD to UHD BluRay?
Thanks,
Jemima
.