The idea is: if the original audio stream in the file is already compressed (most of the time it is), then you do not need to recompress it – and do not need libmp3lame or any other audio codec! To achieve the “ffmpeg direct stream copy” functionality, you can add one of the two options:
-vcodec copy will direct-stream-copy video (no re-compression),
-acodec copy will direct-stream-copy audio (no re-compression).

In other words, ffmpeg option -acodec copy should just copy the original audio from input file to output file without alteration, and will not require any audio codecs support.

Sample command line could be (in the example, a 1-minute fragment of the input file is just copied into the output file):

ffmpeg -t 00:01:00 -i movie.avi -vcodec copy -acodec copy preview.avi

This tip is based on the information initially obtained from the ffmpeg-user mailing list archive for June of 2005.

Step-by-step:

• Download the compiled ffmpeg with libmp3lame support (direct download links: older version ffmpeg.with.lame and newer version ffmpeg.2007-10-28.with-libmp3lame-support).
• Rename the downloaded executable file to "ffmpeg" (no extension), upload it to the directory on your server (in this example /home/myusername/).
• Download libmp3lame.so.0.
• Upload libmp3lame.so.0 to the same directory where you placed ffmpeg in.
• Create a php file with the following code (remember to change the paths to your own, where you actually uploaded binaries in previous steps):
  PLAIN TEXT
  PHP:

  1. <?php
  2. exec("export LD_LIBRARY_PATH=/home/myusername/");
  3. echo passthru("/home/myusername/ffmpeg -formats");
  4. ?>

• If you access that PHP file with your browser, you should be able to see a list of formats which are supported by ffmpeg, and if you find "EA libmp3lame" somewhere in the output, then it means you now can Encode Audio in libmp3lame!
• If that doesn't work for you: LD_LIBRARY_PATH can be a protected variable in PHP (you can check for this by searching for the "safe_mode_protected_env_vars" value in phpinfo() output). The workaround here can be to write your commands to a file from php, then chmod that file with 0755 permissions (rwx-rx-rx), and run the file through exec(). In this way, PHP is not changing the LD_LIBRARY_PATH, but telling the server to run a file, which tells the server to change it. This method worked for the original author of these instructions.

For passing arguments to the PHP wrapper script - check out PHP's $argv variable (more on this here). If you decided to use shell-script as a wrapper for "export LD_LIBRARY_PATH", then using $1, $2 etc will allow you to pass parameters to the shell script, e.g. in the example below

you could pass "input file" as first argument, "parameters" as second and "output file" as third to make such a wrapper script work.

As Gabe pointed out in my post with compiled ffmpeg Linux binaries, there is a relatively simple method of adding libmp3lame.so.0 file to your shared hosting so that ffmpeg executable will see the library:

You can upload libmp4lame.so as well to the shared hosting site and when you call ffmpeg, call something to set an environment variable right before the call to ffmpeg i.e. in php I’d do exec(”export LD_LIBRARY_PATH=/path/to/lib/with/lame; /path/to/ffmpeg [ffmpegargs]”); That way you can use the uploaded lame. I hope that helps someone as I have been unable to find any info on how to use an uploaded lame. I’ve tried it and it works on godaddy.

Hope this helps.

Update: here's libmp3lame.so.0.0.0 (from slackware 2.4.x, lame-3.97). I have no idea if it'll work in your (shared hosting) environment; it is provided AS IS, use at your own risk etc. I can only state that the archived binary file at the moment of upload was indeed libmp3lame.so.0.0.0 from my elderly Slackware with 2.4.x kernel.