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“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 & stereo mic/line input
- Audio effects including:
- Ring modulator
- FFT passthrough using Accelerate vDSP framework
- Real-time pitch shifting and detection using STFT
- Simple variable speed delay using a ring buffer
- Recursive moving average filter with variable number of points
- Convolution example with variable filter cutoff frequency
- Stereo level meter
- Synthesizer example – sine wave with envelope generator
- iOS 5 features (from Chris Adamson) including:
- MIDI sampler audio unit
- File player audio unit
- Audio unit effects
- Runs on iPad, iPhone, and iPod-Touch
- Open source
- Music by Van Lawton
- Plus everything from MixerHost”
More info: http://zerokidz.com/audiograph/Home.html
