ffmpeg: error while loading shared libraries: libavdevice.so.53
ffmpeg正常安装后执行ffmpeg时出现如下错误：
ffmpeg: error while loading shared libraries: libavdevice.so.53: cannot open shared object file: No such file or directory
解决办法：
vi /etc/ld.so.conf
加入：/usr/local/lib
执行ldconfig
