A .wav file is pretty simple, just an array of amplitudes indexed by time quanta. See if your audio files can be converted to .wav files.

Then, read the amplitudes into a C array (or a D array, even better!) and they're easy to do simple processing on.

I wrote a program a few years ago that would do this, looking for things that looked like clicks and smooth them with a cubic interpolation. It was fun to dink around with it.