What is the algorithm to convert an mp3 file to a wav file?

Question

What is the algorithm to convert an mp3 file to a wav file?

Answer 1

It's non-trivial to say the least. You could get an overview of the algorithm here:

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.26.5956&rep=rep1&type=pdf

But I would suggest using a library for your programming needs, for example:

http://www.ffmpeg.org/

Answer 2

As for the mp3 file, I can offer you mpg123 .net wrapper that is extremely easy to use - you will get the sample for reading the mp3, extracting PCM information from it (this is main part of WAV file - PCM data for the sound).

Please, go here:

http://sourceforge.net/projects/mpg123net/

and download sample code from here:

http://sourceforge.net/projects/mpg123net/files/

Ping me if you need more info/help on the subject.

As aac files are concerned, there is faad project here:

http://www.audiocoding.com/faad2.html

that enables you to do the same with the aac file. If you need .net wrapper, I'm about to put it on sourceforge also.