[FFmpeg-user] FFMPEG SOURCE BUILD QUESTION

[maujhsn]

Can anybody explain why this command doesn't install this program which I
downloaded from source?

tar -xjvf <filename>.tar.bz2 In my case: ffmpeg-linux64-20121206.tar.bz2

It resides in ubuntu at ubuntu:~/Downloads/ffmpeg-linux64-20121206$

WHY DO I GET THIS OUTPUT TO A SIMPLE FFMPEG COMMAND IF THE WHOLE PACKAGE
RESIDES IN THIS PATH?: ubuntu at ubuntu:~/Downloads/ffmpeg-linux64-20121206$
ffmpeg -vn -i desk2E.mkv -ac 2 -ab 128k -ar 44100 output.wav
The program 'ffmpeg' is currently not installed.  You can install it by
typing:
sudo apt-get install ffmpeg

THANKS IN ADVANCE

MJ