Starting with version 1.8.5, MakeMKV comes with libmmbd library as described at viewtopic.php?f=10&t=7008
. This library also emulates libaacs/libbdplus libraries - below are instructions how to setup libmmbd for libaacs/libbdplus emulation. Once done, any libbluray-based application, including VLC player, will be able to open protected blu-ray discs.
These instructions assume that MakeMKV was installed to default location using unmodified makefiles. If it is not the case, you'll have to modify paths to reflect your locations.
Firstly, make sure that the open-source libaacs is not installed - there can be only one libaacs in the system. On debian-based distribution execute the following command to remove stock libaacs
sudo apt-get remove libaacs0
Then, open terminal, navigate to directory where libmmbd is installed, and make a symlink to libaacs and libbdplus. The following commands are for default installation
sudo ln -s libmmbd.so.0 libaacs.so.0
sudo ln -s libmmbd.so.0 libbdplus.so.0
You're done. From now on VLC will automatically use MakeMKV for blu-ray decryption.