Struct VNTextObservation

#[repr(C)]
pub struct VNTextObservation { /* private fields */ }

Available on crate feature VNObservation only.

VNTextObservation Describes a text area detected by the VNRequestNameDetectTextRectangles request.

See also Apple’s documentation

Implementations

impl VNTextObservation

pub unsafe fn characterBoxes( &self, ) -> Option<Retained<NSArray<VNRectangleObservation>>>

Array of individual character bounding boxes found within the observation’s boundingBox.

If the associated request indicated that it is interested in character boxes by setting the VNDetectTextRectanglesRequest reportCharacterBoxes property to true, this property will be non-nil (but may still be empty, depending on the detection results).

impl VNTextObservation

Methods declared on superclass VNRectangleObservation.

pub unsafe fn rectangleObservationWithRequestRevision_topLeft_bottomLeft_bottomRight_topRight( request_revision: NSUInteger, top_left: CGPoint, bottom_left: CGPoint, bottom_right: CGPoint, top_right: CGPoint, ) -> Retained<Self>

👎Deprecated

Available on crate feature objc2-core-foundation only.

Create a synthesized VNRectangleObservation.

Note: The clockwise parameter ordered +[VNRectangleObservation rectangleObservationWithRequestRevision:topLeft:topRight:bottomRight:bottomLeft:] is the preferred initializer.

Parameter requestRevision: The revision of the VNDetectRectanglesRequest that the observation is to be treated as originating from.

Parameter topLeft: The top-left corner of the rectangle in normalized coordinate space.

Parameter bottomLeft: The bottom-left corner of the rectangle in normalized coordinate space.

Parameter bottomRight: The bottom-right corner of the rectangle in normalized coordinate space.

Parameter topRight: The top-right corner of the rectangle in normalized coordinate space.

pub unsafe fn rectangleObservationWithRequestRevision_topLeft_topRight_bottomRight_bottomLeft( request_revision: NSUInteger, top_left: CGPoint, top_right: CGPoint, bottom_right: CGPoint, bottom_left: CGPoint, ) -> Retained<Self>

Available on crate feature objc2-core-foundation only.

Create a synthesized VNRectangleObservation.

Parameter requestRevision: The revision of the VNDetectRectanglesRequest that the observation is to be treated as originating from.

Parameter topLeft: The top-left corner of the rectangle in normalized coordinate space.

Parameter topRight: The top-right corner of the rectangle in normalized coordinate space.

Parameter bottomRight: The bottom-right corner of the rectangle in normalized coordinate space.

Parameter bottomLeft: The bottom-left corner of the rectangle in normalized coordinate space.

impl VNTextObservation

Methods declared on superclass VNDetectedObjectObservation.

pub unsafe fn observationWithBoundingBox(bounding_box: CGRect) -> Retained<Self>

Available on crate feature objc2-core-foundation only.

create a new VNDetectedObjectObservation with a normalized bounding box and a confidence of 1.0.

pub unsafe fn observationWithRequestRevision_boundingBox( request_revision: NSUInteger, bounding_box: CGRect, ) -> Retained<Self>

Available on crate feature objc2-core-foundation only.

impl VNTextObservation

Methods declared on superclass NSObject.

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

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

Methods from Deref<Target = VNRectangleObservation>

pub unsafe fn topLeft(&self) -> CGPoint

Available on crate feature objc2-core-foundation only.

pub unsafe fn topRight(&self) -> CGPoint

Available on crate feature objc2-core-foundation only.

pub unsafe fn bottomLeft(&self) -> CGPoint

Available on crate feature objc2-core-foundation only.

pub unsafe fn bottomRight(&self) -> CGPoint

Available on crate feature objc2-core-foundation only.

Methods from Deref<Target = VNDetectedObjectObservation>

pub unsafe fn boundingBox(&self) -> CGRect

Available on crate feature objc2-core-foundation only.

The bounding box of the detected object. The coordinates are normalized to the dimensions of the processed image, with the origin at the image’s lower-left corner.

pub unsafe fn globalSegmentationMask( &self, ) -> Option<Retained<VNPixelBufferObservation>>

The resulting CVPixelBuffer from requests that generate a segmentation mask for the entire image.

Methods from Deref<Target = VNObservation>

pub unsafe fn uuid(&self) -> Retained<NSUUID>

The unique identifier assigned to an observation.

pub unsafe fn confidence(&self) -> VNConfidence

Available on crate feature VNTypes only.

The level of confidence normalized to [0, 1] where 1 is most confident. The only exception is results coming from VNCoreMLRequest, where confidence values are forwarded as is from relevant CoreML models

Confidence can always be returned as 1.0 if confidence is not supported or has no meaning

pub unsafe fn timeRange(&self) -> CMTimeRange

Available on crate feature objc2-core-media only.

The duration of the observation reporting when first detected and how long it is valid.

The duration of the observation when used with a sequence of buffers. If a request does not support a timeRange or the timeRange is not known, the start time and duration will be set to 0.

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 VNTextObservation

fn as_ref(&self) -> &AnyObject

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

impl AsRef<NSObject> for VNTextObservation

fn as_ref(&self) -> &NSObject

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

impl AsRef<VNDetectedObjectObservation> for VNTextObservation

fn as_ref(&self) -> &VNDetectedObjectObservation

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

impl AsRef<VNObservation> for VNTextObservation

fn as_ref(&self) -> &VNObservation

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

impl AsRef<VNRectangleObservation> for VNTextObservation

fn as_ref(&self) -> &VNRectangleObservation

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

impl AsRef<VNTextObservation> for VNTextObservation

fn as_ref(&self) -> &Self

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

impl Borrow<AnyObject> for VNTextObservation

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for VNTextObservation

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl Borrow<VNDetectedObjectObservation> for VNTextObservation

fn borrow(&self) -> &VNDetectedObjectObservation

Immutably borrows from an owned value.

impl Borrow<VNObservation> for VNTextObservation

fn borrow(&self) -> &VNObservation

Immutably borrows from an owned value.

impl Borrow<VNRectangleObservation> for VNTextObservation

fn borrow(&self) -> &VNRectangleObservation

Immutably borrows from an owned value.

impl ClassType for VNTextObservation

const NAME: &'static str = "VNTextObservation"

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

type Super = VNRectangleObservation

The superclass of this class.

type ThreadKind = <<VNTextObservation 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 CopyingHelper for VNTextObservation

type Result = VNTextObservation

The immutable counterpart of the type, or Self if the type has no immutable counterpart.

impl Debug for VNTextObservation

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

Formats the value using the given formatter.

impl Deref for VNTextObservation

type Target = VNRectangleObservation

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for VNTextObservation

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 VNTextObservation

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSCopying for VNTextObservation

fn copy(&self) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

unsafe fn copyWithZone(&self, zone: *mut NSZone) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

impl NSObjectProtocol for VNTextObservation

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 NSSecureCoding for VNTextObservation

unsafe fn supportsSecureCoding() -> bool

where Self: Sized + ClassType,

impl PartialEq for VNTextObservation

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 VNTextObservation

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

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

impl VNRequestRevisionProviding for VNTextObservation

unsafe fn requestRevision(&self) -> NSUInteger

where Self: Sized + Message,

Available on crate feature VNRequestRevisionProviding only.

The revision of the VNRequest subclass that was used to generate the object that implements this protocol.

impl DowncastTarget for VNTextObservation

impl Eq for VNTextObservation

impl NSCoding for VNTextObservation