from earlier post
"The most easy way to install ffmpeg in CentOS is with yum.
First of all, edit /etc/yum.repos.d/CentOS-Base.repo and add those lines at bottm of file:
[dag]
name=Dag RPM Repository for Centos
baseurl=http://apt.sw.be/redhat/el$releasever/en/$basearch/dag
enabled=1

Then, run command:
yum install ffmpeg"


try this page for better results:

http://dag.wieers.com/rpm/FAQ.php#B

Thanks,
Zine
http://myrealityvirtual.com