Vision · IOS API REFERENCE

TrackOpticalFlowRequest

class · iOS 18.0+ · SDK 27.1

final class TrackOpticalFlowRequest

This request generates an OpticalFlowObservation object that describes the directional change from image to image. The request works at the pixel level, so both images needs to have the same dimensions to successfully perform the request.

Members (13)

get · iOS 18.0+

descriptor

TypeScript

get descriptor(): RequestDescriptor

Swift declaration

final var descriptor: RequestDescriptor { get }

An enum that identifies the request and request revision.

get · iOS 18.0+

regionOfInterest

TypeScript

get regionOfInterest(): NormalizedRect

Swift declaration

final var regionOfInterest: NormalizedRect { get set }

The region of the image in which Vision will perform the request. The rectangle is normalized to the dimensions of the processed image. Its origin is specified relative to the image's lower-left corner. By default, the region of interest will be the full image.

set · iOS 18.0+

regionOfInterest

TypeScript

set regionOfInterest(value: NormalizedRect)

Swift declaration

final var regionOfInterest: NormalizedRect { get set }

method · iOS 18.0+

setComputeDevice

TypeScript

setComputeDevice(computeDevice: (_CoreML_MLComputeDevice) | null, computeStage: ComputeStage): void

Swift declaration

final func setComputeDevice(_ computeDevice: MLComputeDevice?, for computeStage: ComputeStage)

Assigns a compute device for a compute stage. If the parameter `computeDevice` is `nil`, the framework removes any explicit compute device assignment and allows the framework to select the device. Configure any compute device for a given compute stage. When performing a request, the system makes a validity check. Use `supportedComputeStageDevices` to get valid compute devices for a request’s compute stages. - Parameters: - `computeDevice: `The compute device to assign to the compute stage. - `computeStage: `The compute stage.

get · iOS 18.0+

supportedRevisions

TypeScript

static get supportedRevisions(): Array<TrackOpticalFlowRequest_Revision>

Swift declaration

static let supportedRevisions: [TrackOpticalFlowRequest.Revision]

The collection of currently-supported revisions for `TrackOpticalFlowRequest`.

get · iOS 18.0+

computationAccuracy

TypeScript

get computationAccuracy(): TrackOpticalFlowRequest_ComputationAccuracy

Swift declaration

final var computationAccuracy: TrackOpticalFlowRequest.ComputationAccuracy { get set }

set · iOS 18.0+

computationAccuracy

TypeScript

set computationAccuracy(value: TrackOpticalFlowRequest_ComputationAccuracy)

Swift declaration

final var computationAccuracy: TrackOpticalFlowRequest.ComputationAccuracy { get set }

get · iOS 18.0+

frameAnalysisSpacing

TypeScript

get frameAnalysisSpacing(): _CoreMedia_CMTime

Swift declaration

final let frameAnalysisSpacing: CMTime

The reciprocal of maximum rate at which buffers will be processed. The request will not process buffers that fall within the `frameAnalysisSpacing` since the previously performed analysis. The analysis is not done by wall time but by analysis of of the time stamps of the samplebuffers being processed.

get · iOS 18.0+

outputPixelFormatType

TypeScript

get outputPixelFormatType(): SDKHandle

Swift declaration

final var outputPixelFormatType: OSType { get set }

The desired pixel format type of the observation. The default is `kCVPixelFormatType_TwoComponent32Float`.

set · iOS 18.0+

outputPixelFormatType

TypeScript

set outputPixelFormatType(value: SDKHandle)

Swift declaration

final var outputPixelFormatType: OSType { get set }

The desired pixel format type of the observation. The default is `kCVPixelFormatType_TwoComponent32Float`.

get · iOS 18.0+

supportedOutputPixelFormatTypes

TypeScript

get supportedOutputPixelFormatTypes(): Array<SDKHandle>

Swift declaration

final var supportedOutputPixelFormatTypes: [OSType] { get }

The collection of supported pixel format types.

get · iOS 18.0+

revision

TypeScript

get revision(): TrackOpticalFlowRequest_Revision

Swift declaration

final let revision: TrackOpticalFlowRequest.Revision

The request's configured revision.

init · iOS 18.0+

init

TypeScript

static init(revision?: (TrackOpticalFlowRequest_Revision) | null, frameAnalysisSpacing?: (_CoreMedia_CMTime) | null): TrackOpticalFlowRequest

Swift declaration

init(_ revision: TrackOpticalFlowRequest.Revision? = nil, frameAnalysisSpacing: CMTime? = nil)

Skipped declarations

No declarations were skipped in this snapshot.

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