Contents

kAudioUnitProperty_AudioChannelLayout

A read/write AudioChannelLayout data structure valid on the audio unit input and output scopes.

Declaration

var kAudioUnitProperty_AudioChannelLayout: AudioUnitPropertyID { get }

Discussion

The channel order, within a given audio stream, for a specified audio unit element and scope. The number of channels in the layout must match the number of channels set for the scope-element. Each input and output bus in an audio unit can have one instance of this property.

Some audio units require this property. For example, the 3DMixer unit must implement this property on its output bus. If a host application attempts to clear the value of this property on a bus that requires a valid value, the audio unit will return a kAudioUnitErr_InvalidPropertyValue error.

Input and output buses can be in one of three states in regard to Audio channel layout:

  1. Implemented and set

  2. Implemented but not set

  3. Unimplemented

Requesting the value of this property when it is implemented but not set results in a kAudioUnitErr_PropertyNotInUse error.

Use the kAudioUnitProperty_AudioChannelLayout property whenever channel layout is relevant.

For related information, refer to the descriptions for the ScheduledAudioFileRegion and AudioOutputUnitStartAtTimeParams data structures.

See Also

Properties