How to convert aac/amr to pcm in Android

Question

I have several recorded sound files on an Android device which are encoded as aac (in an mp4 container). I also have some which are encoded as amr (in a 3gpp container). I wish to convert both types into raw PCM data values for the purpose of plotting the audio waveform to a Canvas.

Is there a library built into android which can do this conversion? If there is no standard way, what is the most common 3rd party library for this? The vast majority of examples I have found are encoding from PCM to other file formats, and not decoding to PCM.

Thanks.

EDIT: I would prefer not to use NDK if possible.

Answer 1

It seems using ffmpeg is the canonical solution.