Question

I want to apply post-processing to audio from an iPhone user’s music library (i.e. the iPod app). This could happen in a number of ways:

• Piping the media player’s output through an Audio Unit.
• Writing a custom audio output device, and having the media player send audio to it.
• Getting direct access to the files in the user’s music library.

Are any of these things possible? I know all of them would be on the desktop, but what about the iPhone?

Answer 1

I’ve written some sample code that does just this, which is based on some code from Chris Adamson.