Video Not Converting in Backend

Hello

I have installed all the required server software and I have tested converting videos using the command in shell and everything worked.. but when I try to upload the video in the website the videos does not convert its giving me error..

does anyone know whats wrong?

awaiting for your responses.. Thank You

Hello Again

I have found the solution..

the exec function in php.ini was disabled thats why It was not able to convert the video...