[CentOS] ffmpeg

Hi ALL

I am trying to install

rpm -ivh ffmpeg-0.4.9-0.3.20051207.2.el4.rf.i386.rpm
warning: ffmpeg-0.4.9-0.3.20051207.2.el4.rf.i386.rpm: V3 DSA
signature: NOKEY, key ID 6b8d79e6
error: Failed dependencies:
        libImlib2.so.1 is needed by ffmpeg-0.4.9-0.3.20051207.2.el4.rf.i386
        libfaad.so.0 is needed by ffmpeg-0.4.9-0.3.20051207.2.el4.rf.i386
        libpostproc.so.0.0.1 is needed by
ffmpeg-0.4.9-0.3.20051207.2.el4.rf.i386

where do i get packages for the above failed Failed dependencies, How
to determine the package which contains this dependencies

Thanks and Regards

Kaushal