Struct AVAudioMixerNode 

pub struct AVAudioMixerNode { /* private fields */ }

Available on crate features AVAudioMixerNode and AVAudioNode only.

A node that mixes its inputs to a single output.

Mixers may have any number of inputs.

The mixer accepts input at any sample rate and efficiently combines sample rate conversions. It also accepts any channel count and will correctly upmix or downmix to the output channel count.

See also Apple’s documentation

Implementations

impl AVAudioMixerNode

pub unsafe fn init(this: Allocated<Self>) -> Retained<Self>

pub unsafe fn outputVolume(&self) -> c_float

The mixer’s output volume.

This accesses the mixer’s output volume (0.0-1.0, inclusive).

pub unsafe fn setOutputVolume(&self, output_volume: c_float)

Setter for outputVolume.

pub unsafe fn nextAvailableInputBus(&self) -> AVAudioNodeBus

Available on crate feature AVAudioTypes only.

Find an unused input bus.

This will find and return the first input bus to which no other node is connected.

impl AVAudioMixerNode

Methods declared on superclass NSObject.

pub unsafe fn new() -> Retained<Self>

Methods from Deref<Target = AVAudioNode>

pub unsafe fn reset(&self)

Clear a unit’s previous processing state.

pub unsafe fn inputFormatForBus( &self, bus: AVAudioNodeBus, ) -> Retained<AVAudioFormat>

Available on crate features AVAudioFormat and AVAudioTypes only.

Obtain an input bus’s format.

pub unsafe fn outputFormatForBus( &self, bus: AVAudioNodeBus, ) -> Retained<AVAudioFormat>

Available on crate features AVAudioFormat and AVAudioTypes only.

Obtain an output bus’s format.

pub unsafe fn nameForInputBus( &self, bus: AVAudioNodeBus, ) -> Option<Retained<NSString>>

Available on crate feature AVAudioTypes only.

Return the name of an input bus.

pub unsafe fn nameForOutputBus( &self, bus: AVAudioNodeBus, ) -> Option<Retained<NSString>>

Available on crate feature AVAudioTypes only.

Return the name of an output bus.

pub unsafe fn installTapOnBus_bufferSize_format_block( &self, bus: AVAudioNodeBus, buffer_size: AVAudioFrameCount, format: Option<&AVAudioFormat>, tap_block: AVAudioNodeTapBlock, )

Available on crate features AVAudioBuffer and AVAudioFormat and AVAudioTime and AVAudioTypes and block2 only.

Create a “tap” to record/monitor/observe the output of the node.

Parameter bus: the node output bus to which to attach the tap

Parameter bufferSize: the requested size of the incoming buffers in sample frames. Supported range is [100, 400] ms.

Parameter format: If non-nil, attempts to apply this as the format of the specified output bus. This should only be done when attaching to an output bus which is not connected to another node; an error will result otherwise. The tap and connection formats (if non-nil) on the specified bus should be identical. Otherwise, the latter operation will override any previously set format.

Parameter tapBlock: a block to be called with audio buffers

Only one tap may be installed on any bus. Taps may be safely installed and removed while the engine is running.

Note that if you have a tap installed on AVAudioOutputNode, there could be a mismatch between the tap buffer format and AVAudioOutputNode’s output format, depending on the underlying physical device. Hence, instead of tapping the AVAudioOutputNode, it is advised to tap the node connected to it.

E.g. to capture audio from input node:

AVAudioEngine *engine = [[AVAudioEngine alloc] init];
AVAudioInputNode *input = [engine inputNode];
AVAudioFormat *format = [input outputFormatForBus: 0];
[input installTapOnBus: 0 bufferSize: 8192 format: format block: ^(AVAudioPCMBuffer *buf, AVAudioTime *when) {
// ‘buf' contains audio captured from input node at time 'when'
}];
....
// start engine

Safety

tap_block must be a valid pointer.

pub unsafe fn removeTapOnBus(&self, bus: AVAudioNodeBus)

Available on crate feature AVAudioTypes only.

Destroy a tap.

Parameter bus: the node output bus whose tap is to be destroyed

pub unsafe fn engine(&self) -> Option<Retained<AVAudioEngine>>

Available on crate feature AVAudioEngine only.

The engine to which the node is attached (or nil).

pub unsafe fn numberOfInputs(&self) -> NSUInteger

The node’s number of input busses.

pub unsafe fn numberOfOutputs(&self) -> NSUInteger

The node’s number of output busses.

pub unsafe fn lastRenderTime(&self) -> Option<Retained<AVAudioTime>>

Available on crate feature AVAudioTime only.

Obtain the time for which the node most recently rendered.

Will return nil if the engine is not running or if the node is not connected to an input or output node.

pub unsafe fn AUAudioUnit(&self) -> Retained<AUAudioUnit>

Available on crate feature objc2-audio-toolbox and non-watchOS only.

An AUAudioUnit wrapping or underlying the implementation’s AudioUnit.

This provides an AUAudioUnit which either wraps or underlies the implementation’s AudioUnit, depending on how that audio unit is packaged. Applications can interact with this AUAudioUnit to control custom properties, select presets, change parameters, etc.

No operations that may conflict with state maintained by the engine should be performed directly on the audio unit. These include changing initialization state, stream formats, channel layouts or connections to other audio units.

pub unsafe fn latency(&self) -> NSTimeInterval

The processing latency of the node, in seconds.

This property reflects the delay between when an impulse in the audio stream arrives at the input vs. output of the node. This should reflect the delay due to signal processing (e.g. filters, FFT’s, etc.), not delay or reverberation which is being applied as an effect. A value of zero indicates either no latency or an unknown latency.

pub unsafe fn outputPresentationLatency(&self) -> NSTimeInterval

The maximum render pipeline latency downstream of the node, in seconds.

This describes the maximum time it will take for the audio at the output of a node to be presented. For instance, the output presentation latency of the output node in the engine is:

• zero in manual rendering mode
• the presentation latency of the device itself when rendering to an audio device (see AVAudioIONode(presentationLatency)) The output presentation latency of a node connected directly to the output node is the output node’s presentation latency plus the output node’s processing latency (see latency).

For a node which is exclusively in the input node chain (i.e. not connected to engine’s output node), this property reflects the latency for the output of this node to be presented at the output of the terminating node in the input chain.

A value of zero indicates either an unknown or no latency.

Note that this latency value can change as the engine is reconfigured (started/stopped, connections made/altered downstream of this node etc.). So it is recommended not to cache this value and fetch it whenever it’s needed.

Methods from Deref<Target = NSObject>

pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>

pub fn class(&self) -> &'static AnyClass

Dynamically find the class of this object.

Panics

May panic if the object is invalid (which may be the case for objects returned from unavailable init/new methods).

Example

Check that an instance of NSObject has the precise class NSObject.

use objc2::ClassType;
use objc2::runtime::NSObject;

let obj = NSObject::new();
assert_eq!(obj.class(), NSObject::class());

pub unsafe fn get_ivar<T>(&self, name: &str) -> &T

where T: Encode,

👎Deprecated: this is difficult to use correctly, use Ivar::load instead.

Use Ivar::load instead.

Safety

The object must have an instance variable with the given name, and it must be of type T.

See Ivar::load_ptr for details surrounding this.

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: DowncastTarget,

Attempt to downcast the object to a class of type T.

This is the reference-variant. Use Retained::downcast if you want to convert a retained object to another type.

Mutable classes

Some classes have immutable and mutable variants, such as NSString and NSMutableString.

When some Objective-C API signature says it gives you an immutable class, it generally expects you to not mutate that, even though it may technically be mutable “under the hood”.

So using this method to convert a NSString to a NSMutableString, while not unsound, is generally frowned upon unless you created the string yourself, or the API explicitly documents the string to be mutable.

See Apple’s documentation on mutability and on isKindOfClass: for more details.

Generic classes

Objective-C generics are called “lightweight generics”, and that’s because they aren’t exposed in the runtime. This makes it impossible to safely downcast to generic collections, so this is disallowed by this method.

You can, however, safely downcast to generic collections where all the type-parameters are AnyObject.

Panics

This works internally by calling isKindOfClass:. That means that the object must have the instance method of that name, and an exception will be thrown (if CoreFoundation is linked) or the process will abort if that is not the case. In the vast majority of cases, you don’t need to worry about this, since both root objects NSObject and NSProxy implement this method.

Examples

Cast an NSString back and forth from NSObject.

use objc2::rc::Retained;
use objc2_foundation::{NSObject, NSString};

let obj: Retained<NSObject> = NSString::new().into_super();
let string = obj.downcast_ref::<NSString>().unwrap();
// Or with `downcast`, if we do not need the object afterwards
let string = obj.downcast::<NSString>().unwrap();

Try (and fail) to cast an NSObject to an NSString.

use objc2_foundation::{NSObject, NSString};

let obj = NSObject::new();
assert!(obj.downcast_ref::<NSString>().is_none());

Try to cast to an array of strings.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);
// This is invalid and doesn't type check.
let arr = arr.downcast_ref::<NSArray<NSString>>();

This fails to compile, since it would require enumerating over the array to ensure that each element is of the desired type, which is a performance pitfall.

Downcast when processing each element instead.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);

for elem in arr {
    if let Some(data) = elem.downcast_ref::<NSString>() {
        // handle `data`
    }
}

Trait Implementations

impl AVAudio3DMixing for AVAudioMixerNode

unsafe fn renderingAlgorithm(&self) -> AVAudio3DMixingRenderingAlgorithm

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Type of rendering algorithm used

unsafe fn setRenderingAlgorithm( &self, rendering_algorithm: AVAudio3DMixingRenderingAlgorithm, )

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for renderingAlgorithm.

unsafe fn sourceMode(&self) -> AVAudio3DMixingSourceMode

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Controls how individual channels of an input bus are rendered

unsafe fn setSourceMode(&self, source_mode: AVAudio3DMixingSourceMode)

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for sourceMode.

unsafe fn pointSourceInHeadMode(&self) -> AVAudio3DMixingPointSourceInHeadMode

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

In-head rendering choice for AVAudio3DMixingSourceModePointSource in AVAudio3DMixingRenderingAlgorithmAuto

unsafe fn setPointSourceInHeadMode( &self, point_source_in_head_mode: AVAudio3DMixingPointSourceInHeadMode, )

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for pointSourceInHeadMode.

unsafe fn rate(&self) -> c_float

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Changes the playback rate of the input signal

unsafe fn setRate(&self, rate: c_float)

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for rate.

unsafe fn reverbBlend(&self) -> c_float

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Controls the blend of dry and reverb processed audio

unsafe fn setReverbBlend(&self, reverb_blend: c_float)

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for reverbBlend.

unsafe fn obstruction(&self) -> c_float

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Simulates filtering of the direct path of sound due to an obstacle

unsafe fn setObstruction(&self, obstruction: c_float)

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for obstruction.

unsafe fn occlusion(&self) -> c_float

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Simulates filtering of the direct and reverb paths of sound due to an obstacle

unsafe fn setOcclusion(&self, occlusion: c_float)

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for occlusion.

unsafe fn position(&self) -> AVAudio3DPoint

where Self: Sized + Message,

Available on crate features AVAudioMixing and AVAudioTypes only.

The location of the source in the 3D environment

unsafe fn setPosition(&self, position: AVAudio3DPoint)

where Self: Sized + Message,

Available on crate features AVAudioMixing and AVAudioTypes only.

Setter for position.

impl AVAudioMixing for AVAudioMixerNode

unsafe fn destinationForMixer_bus( &self, mixer: &AVAudioNode, bus: AVAudioNodeBus, ) -> Option<Retained<AVAudioMixingDestination>>

where Self: Sized + Message,

Available on crate features AVAudioNode and AVAudioTypes and AVAudioMixing only.

Returns the AVAudioMixingDestination object corresponding to specified mixer node and its input bus

unsafe fn volume(&self) -> c_float

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Set a bus’s input volume

unsafe fn setVolume(&self, volume: c_float)

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for volume.

impl AVAudioStereoMixing for AVAudioMixerNode

unsafe fn pan(&self) -> c_float

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Set a bus’s stereo pan

unsafe fn setPan(&self, pan: c_float)

where Self: Sized + Message,

Available on crate feature AVAudioMixing only.

Setter for pan.

impl AsRef<AVAudioMixerNode> for AVAudioMixerNode

fn as_ref(&self) -> &Self

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<AVAudioNode> for AVAudioMixerNode

fn as_ref(&self) -> &AVAudioNode

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<AnyObject> for AVAudioMixerNode

fn as_ref(&self) -> &AnyObject

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<NSObject> for AVAudioMixerNode

fn as_ref(&self) -> &NSObject

Converts this type into a shared reference of the (usually inferred) input type.

impl Borrow<AVAudioNode> for AVAudioMixerNode

fn borrow(&self) -> &AVAudioNode

Immutably borrows from an owned value.

impl Borrow<AnyObject> for AVAudioMixerNode

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for AVAudioMixerNode

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for AVAudioMixerNode

const NAME: &'static str = "AVAudioMixerNode"

The name of the Objective-C class that this type represents.

type Super = AVAudioNode

The superclass of this class.

type ThreadKind = <<AVAudioMixerNode as ClassType>::Super as ClassType>::ThreadKind

Whether the type can be used from any thread, or from only the main thread.

fn class() -> &'static AnyClass

Get a reference to the Objective-C class that this type represents.

fn as_super(&self) -> &Self::Super

Get an immutable reference to the superclass.

impl Debug for AVAudioMixerNode

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Deref for AVAudioMixerNode

type Target = AVAudioNode

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Hash for AVAudioMixerNode

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Message for AVAudioMixerNode

fn retain(&self) -> Retained<Self>

where Self: Sized,

Increment the reference count of the receiver.

impl NSObjectProtocol for AVAudioMixerNode

fn isEqual(&self, other: Option<&AnyObject>) -> bool

where Self: Sized + Message,

Check whether the object is equal to an arbitrary other object.

fn hash(&self) -> usize

where Self: Sized + Message,

An integer that can be used as a table address in a hash table structure.

fn isKindOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of the class, or one of its subclasses.

fn is_kind_of<T>(&self) -> bool

where T: ClassType, Self: Sized + Message,

👎Deprecated: use isKindOfClass directly, or cast your objects with AnyObject::downcast_ref

Check if the object is an instance of the class type, or one of its subclasses.

fn isMemberOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of a specific class, without checking subclasses.

fn respondsToSelector(&self, aSelector: Sel) -> bool

where Self: Sized + Message,

Check whether the object implements or inherits a method with the given selector.

fn conformsToProtocol(&self, aProtocol: &AnyProtocol) -> bool

where Self: Sized + Message,

Check whether the object conforms to a given protocol.

fn description(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object.

fn debugDescription(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object to use when debugging.

fn isProxy(&self) -> bool

where Self: Sized + Message,

Check whether the receiver is a subclass of the NSProxy root class instead of the usual NSObject.

fn retainCount(&self) -> usize

where Self: Sized + Message,

The reference count of the object.

impl PartialEq for AVAudioMixerNode

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RefEncode for AVAudioMixerNode

const ENCODING_REF: Encoding = <AVAudioNode as ::objc2::RefEncode>::ENCODING_REF

The Objective-C type-encoding for a reference of this type.

impl DowncastTarget for AVAudioMixerNode

impl Eq for AVAudioMixerNode