import UIKit
import CoreImage // 引入CoreImage
class ViewController: UIViewController {
 @IBOutlet weak var personPic: UIImageView!

 override func viewDidLoad() {
 super.viewDidLoad()

 personPic.image = UIImage(named: "face-1")
 // 調用detect
 detect()

 }
 //MARK: - 識別面部
 func detect() {
 // 創(chuàng)建personciImage變量保存從故事板中的UIImageView提取圖像并將其轉換為CIImage，使用Core Image時需要用CIImage
 guard let personciImage = CIImage(image: personPic.image!) else {
  return
 }
 // 創(chuàng)建accuracy變量并設為CIDetectorAccuracyHigh，可以在CIDetectorAccuracyHigh(較強的處理能力)與CIDetectorAccuracyLow(較弱的處理能力)中選擇，因為想讓準確度高一些在這里選擇CIDetectorAccuracyHigh
 let accuracy = [CIDetectorAccuracy: CIDetectorAccuracyHigh]
 // 這里定義了一個屬于CIDetector類的faceDetector變量，并輸入之前創(chuàng)建的accuracy變量
 let faceDetector = CIDetector(ofType: CIDetectorTypeFace, context: nil, options: accuracy)
 // 調用faceDetector的featuresInImage方法，識別器會找到所給圖像中的人臉，最后返回一個人臉數組
 let faces = faceDetector?.features(in: personciImage)
 // 循環(huán)faces數組里的所有face，并將識別到的人臉強轉為CIFaceFeature類型
 for face in faces as! [CIFaceFeature] {

  print("Found bounds are \(face.bounds)")
  // 創(chuàng)建名為faceBox的UIView，frame設為返回的faces.first的frame，繪制一個矩形框來標識識別到的人臉
  let faceBox = UIView(frame: face.bounds)
  // 設置faceBox的邊框寬度為3
  faceBox.layer.borderWidth = 3
  // 設置邊框顏色為紅色
  faceBox.layer.borderColor = UIColor.red.cgColor
  // 將背景色設為clear，意味著這個視圖沒有可見的背景
  faceBox.backgroundColor = UIColor.clear
  // 最后，把這個視圖添加到personPic imageView上
  personPic.addSubview(faceBox)
  // API不僅可以幫助你識別人臉，也可識別臉上的左右眼，我們不在圖像中標識出眼睛，只是給你展示一下CIFaceFeature的相關屬性
  if face.hasLeftEyePosition {
  print("Left eye bounds are \(face.leftEyePosition)")
  }

  if face.hasRightEyePosition {
  print("Right eye bounds are \(face.rightEyePosition)")
  }
 }
 }
}

Found bounds are (314.0, 243.0, 196.0, 196.0)

func detect1() {

 guard let personciImage = CIImage(image: personPic.image!) else { return }
 let accuracy = [CIDetectorAccuracy: CIDetectorAccuracyHigh]
 let faceDetector = CIDetector(ofType: CIDetectorTypeFace, context: nil, options: accuracy)
 let faces = faceDetector?.features(in: personciImage)

 // 轉換坐標系
 let ciImageSize = personciImage.extent.size
 var transform = CGAffineTransform(scaleX: 1, y: -1)
 transform = transform.translatedBy(x: 0, y: -ciImageSize.height)

 for face in faces as! [CIFaceFeature] {
 print("Found bounds are \(face.bounds)") 
 // 應用變換轉換坐標
 var faceViewBounds = face.bounds.applying(transform)
 // 在圖像視圖中計算矩形的實際位置和大小
 let viewSize = personPic.bounds.size
 let scale = min(viewSize.width / ciImageSize.width, viewSize.height / ciImageSize.height)
 let offsetX = (viewSize.width - ciImageSize.width * scale) / 2
 let offsetY = (viewSize.height - ciImageSize.height * scale) / 2

 faceViewBounds = faceViewBounds.applying(CGAffineTransform(scaleX: scale, y: scale))
 faceViewBounds.origin.x += offsetX
 faceViewBounds.origin.y += offsetY

 let faceBox = UIView(frame: faceViewBounds)
 faceBox.layer.borderWidth = 3
 faceBox.layer.borderColor = UIColor.red.cgColor
 faceBox.backgroundColor = UIColor.clear
 personPic.addSubview(faceBox)

 if face.hasLeftEyePosition {
  print("Left eye bounds are \(face.leftEyePosition)")
 }

 if face.hasRightEyePosition {
  print("Right eye bounds are \(face.rightEyePosition)")
 }
 }
}

class CameraViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
 @IBOutlet var imageView: UIImageView!
 let imagePicker = UIImagePickerController()

 override func viewDidLoad() {
  super.viewDidLoad()
  imagePicker.delegate = self
 }

 @IBAction func takePhoto(_ sender: AnyObject) {

  if !UIImagePickerController.isSourceTypeAvailable(.camera) {
   return
  }

  imagePicker.allowsEditing = false
  imagePicker.sourceType = .camera

  present(imagePicker, animated: true, completion: nil)
 }

 func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {

  if let pickedImage = info[UIImagePickerControllerOriginalImage] as? UIImage {
   imageView.contentMode = .scaleAspectFit
   imageView.image = pickedImage
  }

  dismiss(animated: true, completion: nil)
  self.detect()
 }

 func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
  dismiss(animated: true, completion: nil)
 }
}

func detect() {
 let imageOptions = NSDictionary(object: NSNumber(value: 5) as NSNumber, forKey: CIDetectorImageOrientation as NSString)
 let personciImage = CIImage(cgImage: imageView.image!.cgImage!)
 let accuracy = [CIDetectorAccuracy: CIDetectorAccuracyHigh]
 let faceDetector = CIDetector(ofType: CIDetectorTypeFace, context: nil, options: accuracy)
 let faces = faceDetector?.features(in: personciImage, options: imageOptions as? [String : AnyObject])

 if let face = faces?.first as? CIFaceFeature {
  print("found bounds are \(face.bounds)")

  let alert = UIAlertController(title: "提示", message: "檢測到了人臉", preferredStyle: UIAlertControllerStyle.alert)
  alert.addAction(UIAlertAction(title: "確定", style: UIAlertActionStyle.default, handler: nil))
  self.present(alert, animated: true, completion: nil)

  if face.hasSmile {
   print("face is smiling");
  }

  if face.hasLeftEyePosition {
   print("左眼的位置: \(face.leftEyePosition)")
  }

  if face.hasRightEyePosition {
   print("右眼的位置: \(face.rightEyePosition)")
  }
 } else {
  let alert = UIAlertController(title: "提示", message: "未檢測到人臉", preferredStyle: UIAlertControllerStyle.alert)
  alert.addAction(UIAlertAction(title: "確定", style: UIAlertActionStyle.default, handler: nil))
  self.present(alert, animated: true, completion: nil)
 }
}

if (face.hasMouthPosition) {
 print("mouth detected")
}