Hi,
I have install ffmpeg.dll in my xampp. i change php.ini file also
extension=ffmpeg.dll and i put avcodec.dll,avformat.dll this file to windows/system32/
but still coming error.
Warning: dl() [function.dl]: Not supported in multithreaded Web servers - use extension=ffmpeg.dll in your php.ini in C:\xampp\htdocs\mp\uploadvideopro.php on line 16
Can't load extension C:\php5/ffmpeg.dll

Try removing the offending code on line 16... should have a dl() command there which is banned on your server.