One more step

Hello,
The doc above is very helpful and very inclusive.
One little thing I would add is you need to make sure that /usr/local/lib is listed in /etc/ld.so.conf in order to avoid getting this error
( ffmpeg: error while loading shared libraries: libavdevice.so.52: cannot open shared object file: No such file or directory )

All you need to do is
vi /etc/ld.so.conf

paste
/usr/local/lib

save,

then do

ldconfig