the same problem i am also getting, i get the dll file from http://raghuram2404.blogspot.in/2012/06/install-ffmpeg-in-wamp-server-20.html and copy that in system32
as per instruction given. I restart the wamp and run phpinfo();
but not getting the ffmpeg in list
or is there other way to generate thumbnail from video upload
Are you extracted and put php_ffmpeg.dll to your php ext folder?
Try to read this link