Important: This sample code may not represent best practices for current development. The project may use deprecated symbols and illustrate technologies and techniques that are no longer recommended.
Relevant replacement documents include:
Version 1.0, 2011-12-06
iOS 5.0+ AURemoteIO example to monitor audio input and play it out (duplex audio I/O)
XCode 4.0 or later, iOS SDK 5.0 or later
iOS 5.0 or later
aurioTouch2 demonstrates use of the remote i/o audio unit (AURemoteIO) for handling audio input and output. The application can display the input audio in one of the forms, a regular time domain waveform, a frequency domain waveform (computed by performing a fast fourier transform on the incoming signal), and a sonogram view (a view displaying the frequency content of a signal over time, with the color signaling relative power, the y axis being frequency and the x as time).
The code in aurioTouch2 uses the remote i/o audio unit (AURemoteIO) for input and output of audio, and OpenGL for display of the input waveform. The application also uses Audio Session Services to manage route changes (as described in Core Audio Overview).
aurioTouch2 supports iOS 5 or later.