SwiftLiftKit

A Swift package for lifting subjects out of images on iOS. Uses Apple's Vision framework to generate foreground masks (iOS 17+) with a person-segmentation fallback (iOS 16+), producing images with transparent backgrounds.

• iOS 16.0+
• Swift 6.0+

Add SwiftLiftKit to your project via Swift Package Manager:

dependencies: [
    .package(url: "https://github.com/mrwinson/SwiftLiftKit.git", from: "1.0.0")
]

Or in Xcode: File > Add Package Dependencies and paste the repository URL.

import SwiftLiftKit

let cutout = try await SwiftLiftKit.liftSubject(from: someUIImage)
// cutout is a UIImage with a transparent background

import SwiftLiftKit

let cutout = try await SwiftLiftKit.captureAndLift(presenter: viewController)

If the mask fails, the original photo is returned by default. Pass preferOriginalIfNoMask: false to throw instead:

let cutout = try await SwiftLiftKit.captureAndLift(
    presenter: viewController,
    preferOriginalIfNoMask: false
)

Use SubjectLiftCameraView to present a camera and receive the cut-out:

import SwiftLiftKit

struct ContentView: View {
    @State private var showCamera = false
    @State private var result: UIImage?

    var body: some View {
        Button("Lift Subject") { showCamera = true }
            .sheet(isPresented: $showCamera) {
                SubjectLiftCameraView { image in
                    result = image
                    showCamera = false
                }
            }
    }
}

SwiftLiftKit throws SubjectLiftError:

1. The input image is normalized to upright RGBA8 sRGB.
2. On iOS 17+, VNGenerateForegroundInstanceMaskRequest isolates the foreground subject.
3. On iOS 16, VNGeneratePersonSegmentationRequest is used as a fallback (people only).
4. The mask is blended with a transparent background using Core Image.

See LICENSE for details.