I'm using Vision framework (DetectFaceLandmarksRequest) with the same code and the same test image to detect face landmarks. On iOS 18 everything works as expected: detected face landmarks align with the face correctly.
But when I run the same code on devices with iOS 26, the landmark coordinates are outside the [0,1] range, which indicates they are out of face bounds.
Fun fact: the old VNDetectFaceLandmarksRequest API works very well without encountering this issue
How I get face landmarks:
private let faceRectangleRequest = DetectFaceRectanglesRequest(.revision3)
private var faceLandmarksRequest = DetectFaceLandmarksRequest(.revision3)
func detectFaces(in ciImage: CIImage) async throws -> FaceTrackingResult {
let faces = try await faceRectangleRequest.perform(on: ciImage)
faceLandmarksRequest.inputFaceObservations = faces
let landmarksResults = try await faceLandmarksRequest.perform(on: ciImage)
...
}
How I show face landmarks in SwiftUI View:
private func convert(
point: NormalizedPoint,
faceBoundingBox: NormalizedRect,
imageSize: CGSize
) -> CGPoint {
let point = point.toImageCoordinates(
from: faceBoundingBox,
imageSize: imageSize,
origin: .upperLeft
)
return point
}
At the same time, it works as expected and gives me the correct results:
region is FaceObservation.Landmarks2D.Region
let points: [CGPoint] = region.pointsInImageCoordinates(
imageSize,
origin: .upperLeft
)
After that, I found that the landmarks are normalized relative to the unalignedBoundingBox. However, I can’t access it in code. Still, using these values for the bounding box works correctly.
Things I've already tried:
Same image input
Tested multiple devices on iOS 26.2 -> always wrong.
Tested multiple devices on iOS 18.7.1 -> always correct.
Environment:
macOS 26.2
Xcode 26.2 (17C52)
Real devices, not simulator
Face Landmarks iOS 18
Face Landmarks iOS 26
