iOS audio processing graph demonstration
“An audio processing graph is a Core Foundation opaque type, AUGraph, that you use to construct and manage an audio unit processing chain. A graph can leverage the capabilities of multiple audio units and multiple render callback functions, allowing you to create nearly any audio processing solution you can imagine.” – From Apple’s “Audio Unit Hosting Guide For iOS”
AudioGraph is a superset of Apple’s MixerHost application.
Features include:
* Mono and stereo mic/line input
* Audio effects including:
o Ring modulator
o FFT passthrough using the Accelerate vDSP framework.
o Real-time variable pitch shifting and detection using STFT
o Simple variable speed delay using a ring buffer
o Recursive moving average filter with variable number of points
o Convolution example with variable filter cutoff frequency
* Stereo level meter
* Synthesizer example – sine wave with an envelope generator
* iOS 5 features (from Chris Adamson) including:
o MIDI sampler audio unit
o file player audio unit
o audio unit effects
* Runs on iPad, iPhone, and iPod-Touch
* Basic audio session management including detection of input devices and available channels
* Commented source code.
* Original music by Van Lawton
* Plus everything from MixerHost
Requirements:
* A device that runs iOS 5.x
* Headphones.
Instructions:
Launch the app and press Play.
Source code, documentation, support:
http://zerokidz.com/audiograph
audiograph@zerokidz.com