我正在使用 Firebase ML-Kit 进行人脸检测，现在我想实现眨眼，但我无法检测到眨眼。我总是得到 leftEyeOpenProbability 和 rightEyeOpenProbability 1.0。我正在使用与https://github.com/firebase/quickstart-ios/tree/master/mlvision相同的以下代码
请帮助我如何实现眨眼功能。
func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {
guard let imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer) else {
print("Failed to get image buffer from sample buffer.")
return
}
let visionImage = VisionImage(buffer: sampleBuffer)
let metadata = VisionImageMetadata()
let visionOrientation = visionImageOrientation(from:imageOrientation(fromDevicePosition: .front))
metadata.orientation = visionOrientation
visionImage.metadata = metadata
let imageWidth = CGFloat(CVPixelBufferGetWidth(imageBuffer))
let imageHeight = CGFloat(CVPixelBufferGetHeight(imageBuffer))
detectFacesOnDevice(in: visionImage, width: imageWidth, height: imageHeight)
}
public func visionImageOrientation(
from imageOrientation: UIImage.Orientation
) -> VisionDetectorImageOrientation {
switch imageOrientation {
case .up:
return .topLeft
case .down:
return .bottomRight
case .left:
return .leftBottom
case .right:
return .rightTop
case .upMirrored:
return .topRight
case .downMirrored:
return .bottomLeft
case .leftMirrored:
return .leftTop
case .rightMirrored:
return .rightBottom
}
}
public func imageOrientation(
fromDevicePosition devicePosition: AVCaptureDevice.Position = .back
) -> UIImage.Orientation {
var deviceOrientation = UIDevice.current.orientation
if deviceOrientation == .faceDown || deviceOrientation == .faceUp ||
deviceOrientation == .unknown {
deviceOrientation = currentUIOrientation()
}
switch deviceOrientation {
case .portrait:
return devicePosition == .front ? .leftMirrored : .right
case .landscapeLeft:
return devicePosition == .front ? .downMirrored : .up
case .portraitUpsideDown:
return devicePosition == .front ? .rightMirrored : .left
case .landscapeRight:
return devicePosition == .front ? .upMirrored : .down
case .faceDown, .faceUp, .unknown:
return .up
}
}
private func currentUIOrientation() -> UIDeviceOrientation {
let deviceOrientation = { () -> UIDeviceOrientation in
switch UIApplication.shared.statusBarOrientation {
case .landscapeLeft:
return .landscapeRight
case .landscapeRight:
return .landscapeLeft
case .portraitUpsideDown:
return .portraitUpsideDown
case .portrait, .unknown:
return .portrait
}
}
guard Thread.isMainThread else {
var currentOrientation: UIDeviceOrientation = .portrait
DispatchQueue.main.sync {
currentOrientation = deviceOrientation()
}
return currentOrientation
}
return deviceOrientation()
}
private func detectFacesOnDevice(in image: VisionImage, width: CGFloat, height: CGFloat) {
let options = VisionFaceDetectorOptions()
options.performanceMode = .accurate
options.landmarkMode = .all
options.isTrackingEnabled = true
options.contourMode = .all
let faceDetector = vision.faceDetector(options: options)
faceDetector.process(image, completion: { features, error in
if let error = error {
print(error.localizedDescription)
return
}
guard error == nil, let features = features, !features.isEmpty else {
//self.removeDetectionAnnotations()
print("On-Device face detector returned no results.")
return
}
//self.removeDetectionAnnotations()
for face in features {
let angleY = face.headEulerAngleY
let angleZ = face.headEulerAngleZ
let smilingProbability = face.smilingProbability
let leftEyeOpenProbability = face.leftEyeOpenProbability
let rightEyeOpenProbability = face.rightEyeOpenProbability
self.infoLabel.text = "right eye open probablity-- \(rightEyeOpenProbability)"
}
})
}