Struct CNAssetSpatialAudioInfo 

pub struct CNAssetSpatialAudioInfo { /* private fields */ }

Available on crate feature CNSpatialAudio only.

A helper class to inspect recordings made when Spatial Audio setting is turned on. An instance of this class contains the default audio track with Spatial Audio, metadata read from the file that can be applied during to enhance the playback experience. This class also provides tunable parameters to change the intensity & mode of the playback experience.

The goal of this class is to assist users operate on assets in which audio has been captured in multiple formats like Spatial Audio and Stereo to allow more audio customization. Users can audition playback of this asset with an immersive audio rendering effect applied by fetching an AVAudioMix containing the necessary metadata serialized in the file as well as any user supplied changes. Once the results of the audition are satisfactory, clients can create a copy of the asset with the audio effect burned in.

See also Apple’s documentation

Implementations

impl CNAssetSpatialAudioInfo

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

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

pub unsafe fn isSupported() -> bool

Indicates whether the current device supports Audio Mix.

pub unsafe fn checkIfContainsSpatialAudio_completionHandler( asset: &AVAsset, completion_handler: &DynBlock<dyn Fn(Bool)>, )

Available on crate features block2 and objc2-av-foundation only.

Check if asset meets all the requirements to operate with Spatial Audio and its accompanying effects

Parameter asset: An instance of AVAsset.

Parameter completionHandler: Completion handler to return the result

Returns: Boolean

pub unsafe fn loadFromAsset_completionHandler( asset: &AVAsset, completion_handler: &DynBlock<dyn Fn(*mut CNAssetSpatialAudioInfo, *mut NSError)>, )

Available on crate features block2 and objc2-av-foundation only.

Returns an instance of CNAssetAudioInfo for an AVAsset object asynchronously.

Parameter asset: An instance of AVAsset

Parameter completionHandler: Completion handler to return the result

Returns: An instance of CNAssetSpatialAudioInfo delivered via the completion handler or an error on failure

impl CNAssetSpatialAudioInfo

Properties.

pub unsafe fn defaultSpatialAudioTrack(&self) -> Retained<AVAssetTrack>

Available on crate feature objc2-av-foundation only.

default AVAssetTrack containing Spatial Audio

This property is not atomic.

Safety

This might not be thread-safe.

pub unsafe fn defaultEffectIntensity(&self) -> c_float

default effect intensity value as provided by the system. Supported range is [0.0-1.0]

This property is not atomic.

Safety

This might not be thread-safe.

pub unsafe fn defaultRenderingStyle(&self) -> CNSpatialAudioRenderingStyle

default rendering style as provided by the system

This property is not atomic.

Safety

This might not be thread-safe.

pub unsafe fn spatialAudioMixMetadata(&self) -> Retained<NSData>

The result of audio analysis during recording which contains metadata necessary to properly configure the Audio Mix feature during playback or editing.. Can be used with AUAudioUnit instances that support AudioUnitPropertyID kProperty_SpatialAudioMixMetadata

This property is not atomic.

Safety

This might not be thread-safe.

impl CNAssetSpatialAudioInfo

SynthesizeAVFoundationObjects.

pub unsafe fn audioMixWithEffectIntensity_renderingStyle( &self, effect_intensity: c_float, rendering_style: CNSpatialAudioRenderingStyle, ) -> Retained<AVAudioMix>

Available on crate feature objc2-av-foundation only.

returns an instance of AVAudioMix encapsulating all spatial audio related data with specified effect intensity and rendering style.

Returns an AVAudioMix containing all the necessary state to operate on the asset with Spatial Audio effects enabled

pub unsafe fn assetReaderOutputSettingsForContentType( &self, content_type: CNSpatialAudioContentType, ) -> Retained<NSDictionary<NSString, AnyObject>>

Returns a dictionary of settings and the source track that should be used to fetch LPCM samples from this track with the effect applied

Use the returned NSDictionary with the defaulSpatialAudioTrack to initialize an instance of AVAssetReaderAudioMixOutput

pub unsafe fn assetWriterInputSettingsForContentType( &self, content_type: CNSpatialAudioContentType, ) -> Retained<NSDictionary<NSString, AnyObject>>

Returns a dictionary of settings that should be used to encode LPCM samples using AVAssetWriterInput

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 AsRef<AnyObject> for CNAssetSpatialAudioInfo

fn as_ref(&self) -> &AnyObject

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

impl AsRef<CNAssetSpatialAudioInfo> for CNAssetSpatialAudioInfo

fn as_ref(&self) -> &Self

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

impl AsRef<NSObject> for CNAssetSpatialAudioInfo

fn as_ref(&self) -> &NSObject

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

impl Borrow<AnyObject> for CNAssetSpatialAudioInfo

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for CNAssetSpatialAudioInfo

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for CNAssetSpatialAudioInfo

const NAME: &'static str = "CNAssetSpatialAudioInfo"

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

type Super = NSObject

The superclass of this class.

type ThreadKind = <<CNAssetSpatialAudioInfo 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 CNAssetSpatialAudioInfo

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

Formats the value using the given formatter.

impl Deref for CNAssetSpatialAudioInfo

type Target = NSObject

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for CNAssetSpatialAudioInfo

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 CNAssetSpatialAudioInfo

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSObjectProtocol for CNAssetSpatialAudioInfo

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 CNAssetSpatialAudioInfo

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 CNAssetSpatialAudioInfo

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

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

impl DowncastTarget for CNAssetSpatialAudioInfo

impl Eq for CNAssetSpatialAudioInfo

impl Send for CNAssetSpatialAudioInfo

impl Sync for CNAssetSpatialAudioInfo