I’ve installed PiTiVi, a linux based video editor, but the editor doesnt come with the codecs (for viewing/playing multimedia VLC is great and comes with its own internal codecs).  To load all the codecs do the following:

1)  First add  RPM Fusion  in the list of repositories that YUM will use to search for installers:

sudo yum localinstall –nogpgcheck http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm

2) Next install the codecs.

sudo yum install gstreamer-plugins-good gstreamer-plugins-bad gstreamer-plugins-bad-free gstreamer-plugins-bad-nonfree gstreamer-plugins-ugly gstreamer-ffmpeg xvidcore xine-lib-extras-freeworld

3) Restart the multi-media app and it should work.