Convert audio files

[eloan]

Hi,

 

In my app I need convert different audio files to mp3, which seems to be more complicated than I thought. To put it straight: I'm a noob at linux. PHP isn't a problem but as soon as I need to do something more advanced in linux I'm lost.

 

So my problem:

 

I want to convert .m4a to .mp3 files, which I figured out works with FAAD2 and LAME. Now this might not be the best or nicest way, but it works. So the commands i use in the shell are:

$ faad file.m4a

#this converts the file to .wav

$ lame file.wav file.mp3

#this converts the file to .mp3

 

This works fine, but as soon as I try to execute the code with PHP the problems start

shell_exec("faad file.m4a") 

just returns an empty string and executes no command

the strange thing is that when executing

shell_exec("faad")

it returns Usage:faad infile.aac....so faad seems to be found

 

When executing lame, nothing happens at all. even

shell_exec("lame")

returns an empty string

 

I installed lame and faad as root, so there might be some kind of rights problem, but I really have no clue how to solve it..

don't know if this info helps but "which lame", and "which faad" return "/usr/local/bin/lame" and "/usr/bin/faad/"

 

thanks for your help

greets from switzerland