copy step written on stackoverflow to install FFMP

Question

I'm working on project for converting youtube videos into mp3 format and found this also to install ffmpeg on wamp server Install FFMPEG on WAMP and try other links also but ffmpeg extension is not installing so I also checked it at phpinfo to confirm its installed or not but not installed and I've windows 7 64, wampserver 2.4, apache 2.4.4 and php version is 5.4.12 I don't know what am I missing, I spent my 6 hours to figure out but extension of ffmpeg is not installed yet please tell me what am I doing wrong?

Now after that I'm getting popup message twice when I start wamp server `PHP Startup: Unable to load dynamic library

c:/wamp/bin/php/php5.4.12/ext/php_ffmpeg.dll' - %1 is not a valid Win32 application.