1. CoreAudio
Cocoaheads 2013, Maxime Bokobza

2. HexASound

3. CoreAudio

4. CoreAudio
Mixer Graph
Effect RemoteIO

5. AUGraph
AUGraphInitialize()
AUGraphNew()
AUGraphOpen()
AUGraphClose()
AUGraphStart()
AUGraphStop()
AUGraphUninitialize()

6. AudioComponentDescription
componentManufacturer
ex: kAudioUnitManufacturer_Apple
componentType
ex: kAudioUnitType_Mixer
kAudioUnitType_Effect
kAudioUnitType_Output
componentSubType
ex: kAudioUnitSubType_MultiChannelMixer
kAudioUnitSubType_Delay
kAudioUnitSubType_RemoteIO

7. AUNode
AUGraphAddNode()
AUGraphConnectNodeInput()

8. AudioUnit
AUGraphNodeInfo()
Audio Unit Properties
Audio Unit Parameters

9. Audio Unit Properties
AudioUnitSetProperty()
AudioUnitGetProperty()
PropertyID
ex:
kAudioUnitProperty_StreamFormat
kAudioUnitProperty_BypassEffect
kAudioUnitProperty_CPULoad
AudioUnitScope
ex:
kAudioUnitScope_Global
kAudioUnitScope_Output

10. Audio Unit Parameters
AudioUnitSetParameter()
AudioUnitGetParameter()
ParameterID
ex:
kBandpassParam_CenterFrequency
kMultiChannelMixerParam_Volume

11. AURenderCallbackStruct
AUGraphSetNodeInputCallback()
static OSStatus renderInput(
!void *inRefCon,
!AudioUnitRenderActionFlags *ioActionFlags,
!const AudioTimeStamp *inTimeStamp,
!UInt32 inBusNumber,
!UInt32 inNumberFrames,
!AudioBufferList *ioData)

12. Links
• http://www.dribin.org/dave/resources/
files/2010/
ipdcchi_Dribin_AudioUnits.pdf
• http://izotope.fileburst.com/guides/
iZotope_iOS_Audio_Programming_Guide.pdf
• http://www.subfurther.com/blog/
2009/04/28/an-iphone-core-audio-brain-
dump/
• http://www.slideshare.net/invalidname/
core-audio-cranks-it-up

13. Démo
http://github.com/maxbok/CoreAudioTemplate

14. One more thing

15. CoreMidi

16. Enable MIDI out
[[MIDINetworkSession
defaultSession] setEnabled:YES]
MIDIClientCreate()
MIDIOutputPortCreate()

17. Send an event
MIDIPacketListInit()
MIDIPacketListAdd()
MIDISend()

18. Disable MIDI out
[[MIDINetworkSession
defaultSession] setEnabled:NO]
MIDIClientDispose()

19. Links
•http://goodliffe.blogspot.fr/
2010/10/using-coremidi-in-
ios-example.html?m=1
•https://github.com/
petegoodliffe/PGMidi
•http://www.onicos.com/staff/
iz/formats/midi-event.html

20. Démo
http://github.com/maxbok/CoreMIDITemplate