AEAudioUnitInputModule Class Reference

Audio input module. More...

#import <AEAudioUnitInputModule.h>

Inherits AEModule.

Instance Methods
(BOOL)	- setup:
	Setup (optional)
(BOOL)	- start:
	Start the audio unit.
(void)	- stop
	Stop the audio unit.
(AudioUnit _Nullable)	- AEAudioUnitInputModuleGetAudioUnit
	Get access to audio unit.
(AudioTimeStamp)	- AEAudioUnitInputModuleGetInputTimestamp
	Get the last received input timestamp.
(AESeconds)	- AEAudioUnitInputModuleGetInputLatency
	Get the input latency.
Instance Methods inherited from AEModule
(instancetype _Nullable)	- initWithRenderer:
	Initializer.
(instancetype _Nonnull)	- NS_UNAVAILABLE
(void)	- rendererDidChangeSampleRate
	Notifies the module that the renderer's sample rate has changed.
(void)	- rendererDidChangeNumberOfChannels
	Notifies the module that the renderer's channel count has changed.

Properties
AudioUnit _Nullable	audioUnit
	The audio unit.
BOOL	running
	Whether unit is currently active.
int	numberOfInputChannels
	The current number of input channels (key-value observable)
double	inputGain
	The input gain level (as power ratio)
BOOL	latencyCompensation
	Whether to automatically perform latency compensation (default YES)
Properties inherited from AEModule
AEModuleProcessFunc _Nonnull	processFunction
	Process function.
AEModuleIsActiveFunc _Nullable	isActiveFunction
	Active test function.
AERenderer *_Nullable	renderer
	The renderer.

Detailed Description

Audio input module.

This module receives audio input from the system audio hardware, and pushes a buffer onto the stack containing the received audio. The pushed buffer has the same channel count as the currently-attached audio hardware, accessible via the "numberOfInputChannels" property.

It's recommended that you do not create an instance of this class directly; instead, use the instance returned from AEAudioUnitOutput's inputModule property, which uses the same underlying audio unit instance as the output.

Method Documentation

- (BOOL) setup:

(NSError *__autoreleasing _Nullable *_Nullable)

error

Setup (optional)

You may call this method prior to start: to set up the rendering resources. Once this is called, the audioUnit property will yield a valid audio unit instance. If you do not use this method, it will be called automatically the first time start: is called.

Note that if this module was retrieved from AEAudioUnitOutput, this will do nothing.

Parameters

error

If an error occured and this is not nil, it will be set to the error on output

Returns

YES on success, NO on failure

- (BOOL) start:

(NSError *__autoreleasing _Nullable *_Nullable)

error

Start the audio unit.

You need to start the audio unit to be able to begin getting audio input.

Parameters

error

If an error occured and this is not nil, it will be set to the error on output

Returns

YES on success, NO on failure

- (void) stop

Stop the audio unit.

- (AudioUnit _Nullable) AEAudioUnitInputModuleGetAudioUnit

(__unsafe_unretained AEAudioUnitInputModule *_Nonnull)

module

Get access to audio unit.

Available for realtime thread usage

Parameters

module

The module instance

Returns

The audio

- (AudioTimeStamp) AEAudioUnitInputModuleGetInputTimestamp

(__unsafe_unretained AEAudioUnitInputModule *_Nonnull)

module

Get the last received input timestamp.

This gives access to the most recent AudioTimeStamp associated with input audio. Use this to perform synchronization.

Parameters

module

The module instance

Returns

The most recent audio timestamp

- (AESeconds) AEAudioUnitInputModuleGetInputLatency

(__unsafe_unretained AEAudioUnitInputModule *_Nonnull)

module

Get the input latency.

This function returns the hardware input latency, in seconds. If you have disabled latency compensation, and timing is important in your app, then you should factor this value into your timing calculations.

Parameters

module

The module instance

Returns

The current input latency

Property Documentation

- (AudioUnit _Nullable) audioUnit

readnonatomicassign

The audio unit.

- (BOOL) running

readnonatomicassign

Whether unit is currently active.

- (int) numberOfInputChannels

readnonatomicassign

The current number of input channels (key-value observable)

- (double) inputGain

readwritenonatomicassign

The input gain level (as power ratio)

- (BOOL) latencyCompensation

readwritenonatomicassign

Whether to automatically perform latency compensation (default YES)

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The documentation for this class was generated from the following file:

• AEAudioUnitInputModule.h