We have made a simple ffmpeg-php installer for CentOS servers running CWP.
To install FFMPEG and ffmpeg-php in your CWP, go to PHP Settings --> FFMPEG Installer.

Installation will run in a background, once you click on the installer button.
You can tail/monitor your installer log from the shell or get back in 10-20 minutes to check if the installation is completed.

FFMEPG bin path: /usr/bin/ffmpeg