/usr/lib/x86_64-linux-gnu/libvisp.so is in libvisp-dev 2.8.0-4.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/libvisp.so.2.8
/usr/lib/x86_64-linux-gnu/libvisp.so.2.8