Enumeration

Audio Session Property Identifiers

Property identifiers used with Audio Session Services in iOS.

Declaration

enum : unsigned int {
    ...
};

Overview

Use these property identifiers in concert with the AudioSessionGetProperty, AudioSessionSetProperty, and AudioSessionAddPropertyListener functions.

Topics

Constants

kAudioSessionProperty_PreferredHardwareSampleRate

Your preferred hardware sample rate for the audio session. A read/write Float64 value. The actual sample rate may be different and can be obtained using the kAudioSessionProperty_CurrentHardwareSampleRate property.

kAudioSessionProperty_PreferredHardwareIOBufferDuration

Your preferred hardware I/O buffer duration in seconds. Do not set this property unless you require lower I/O latency than is provided by default.

kAudioSessionProperty_AudioCategory

The category for the audio session. A read/write UInt32 value. See Audio Session Categories.

kAudioSessionProperty_AudioRouteChange

A CFDictionaryRef object containing the reason the audio route changed along with details on the previous and current audio route.

kAudioSessionProperty_CurrentHardwareSampleRate

Indicates the current hardware sample rate. A read-only Float64 value.

kAudioSessionProperty_CurrentHardwareInputNumberChannels

Indicates the current number of audio hardware input channels. A read-only UInt32 value.

kAudioSessionProperty_CurrentHardwareOutputNumberChannels

Indicates the current number of audio hardware output channels. A read-only UInt32 value.

kAudioSessionProperty_CurrentHardwareOutputVolume

Indicates the current audio output volume as Float32 value between 0.0 and 1.0. Read-only. This value is available to your app by way of a property listener callback function. See AudioSessionAddPropertyListener.

kAudioSessionProperty_CurrentHardwareInputLatency

Indicates the current hardware input latency, in seconds, as a read-only Float32 value.

kAudioSessionProperty_CurrentHardwareOutputLatency

Indicates the current hardware output latency, in seconds, as a read-only Float32 value.

kAudioSessionProperty_CurrentHardwareIOBufferDuration

Indicates the current hardware IO buffer duration, in seconds, as a read-only Float32 value.

kAudioSessionProperty_OtherAudioIsPlaying

Indicates whether or not another app (typically, the iPod app) is currently playing audio. Read-only. A non-zero UInt32 value indicates that other audio is playing.

kAudioSessionProperty_OverrideAudioRoute

Specifies whether or not to override the audio session category’s typical audio route.

kAudioSessionProperty_AudioInputAvailable

Indicates if audio input is available (a nonzero value) or not (a value of 0).

kAudioSessionProperty_ServerDied

Indicates if the audio server has died (indicated by a nonzero UInt32 value) or is still running (a value of 0).

kAudioSessionProperty_OtherMixableAudioShouldDuck

For audio session categories that allow audio mixing with other apps, specifies whether other audio should be reduced in level when your app produces sound. This property has a value of FALSE (0) by default. Set it to a nonzero value to turn on ducking.

kAudioSessionProperty_OverrideCategoryDefaultToSpeaker

Specifies whether or not to route audio to the speaker (instead of to the receiver) when no other audio route, such as a headset, is connected.

kAudioSessionProperty_OverrideCategoryEnableBluetoothInput

Allows a paired Bluetooth device to appear as an available audio input route.

kAudioSessionProperty_InterruptionType

Indicates the type of an end-interruption event.

kAudioSessionProperty_Mode

A read/write UIInt32 value that specifies the audio session mode.

kAudioSessionProperty_InputSources

A CFArrayRef object containing details on the available audio input sources in a USB audio accessory attached through the iPad camera connection kit.

kAudioSessionProperty_OutputDestinations

A CFArrayRef object containing details on the available audio output destinations in a USB audio accessory attached through the iPad camera connection kit.

kAudioSessionProperty_InputSource

A read/write CFNumberRef object that indicates the audio input source, from a USB audio accessory attached through the iPad camera connection kit, that you want to use.

kAudioSessionProperty_OutputDestination

A read/write CFNumberRef object that indicates the audio output destination, from a USB audio accessory attached through the iPad camera connection kit, that you want to use.

kAudioSessionProperty_InputGainAvailable

A read-only UInt32 value that indicates whether or not audio input gain adjustment is available, where a nonzero value means adjustment is available.

kAudioSessionProperty_InputGainScalar

A read/write Float32 value that indicates the audio input gain setting for the active input source.

kAudioSessionProperty_AudioRouteDescription

A read-only CFDictionaryRef object containing information about an audio route.