Error while loading shared libraries: libavcodec.so.57

Hi, I am using ubuntu 14.04, when I do apt-get upgrade I get this error :

System start/stop links for /etc/init.d/kaltura-nginx already exist.
Reloading nginx configuration: /opt/kaltura/nginx/sbin/nginx: error while loading shared libraries: libavcodec.so.57: cannot open shared object file: No such file or directory


kaltura-nginx.postinst FAILED with: 2489 on line 68