aaron@theos-dhues:~/development/pandasrc$ nm /usr/lib/libavformat.* | grep av_register_protocol
         U av_register_protocol
00000020 T av_register_protocol
nm: /usr/lib/libavformat.so: no symbols
nm: /usr/lib/libavformat.so.52: no symbols
nm: /usr/lib/libavformat.so.52.64.2: no symbols