See the details on the FFmpeg downloads page on how to get a copy for your system.
Note: These instructions can be used to set up any command line executable including MPlayer and MEncoder.
You can download an official FFmpeg build from http://ffmpeg.zeranoe.com/builds/. I recommend downloading the “Static” version. Extract the executable called “ffmpeg” (“ffmpeg.exe” if filename extensions are visible) which will probably be located in the “bin” sub-directory of the archive. Move the executable to a directory that is located on the system path (if you downloaded the “Shared” version you will also need to extract the .dll files to the system path). Generally this would be C:\Windows or C:\Windows\System32.
Then open a command prompt and you should be able to execute ffmpeg:
ffmpeg version N-60215-g2a9c507
built on Jan 27 2014 22:08:33 with gcc 4.8.2 (GCC)
configuration: –disable-static –enable-shared –enable-gpl –enable-version3 …
Apple OS X
Most Unix-like systems have a pre-packaged version of FFmpeg that can be installed via the package manager. For systems that use the Advanced Packaging Tool (APT) such as Debian, Ubuntu, and Mint you can execute the following command:
sudo apt-get install ffmpeg
Systems that use the Yellowdog Updater Modified (YUM) package manager such as Red Had and Fedora can use this command:
sudo yum install ffmpeg
Optionally you can download a pre-built static binary for Linux from http://ffmpeg.org/download.html#LinuxBuilds. Unfortunately the FFmpeg project does not provide binaries for other Unix-like systems. Extract the binary file (named “ffmpeg”) from the gzipped archive and move it to a directory that is located on the system path. Generally this would be /bin, /usr/bin, or /usr/local/bin. You should then be able to execute it from a terminal/command line
If there is any error you may need to mark it as “executable”. Use the following example command to do so. Change the directory path dependent on where ffmpeg is located:
sudo chmod +x /usr/bin/ffmpeg