iOS 人脸识别(检测)

import UIKit
import ImageIO
import AVFoundation

class ScanFaceViewController: UIViewController, AVCaptureMetadataOutputObjectsDelegate {

fileprivate var session = AVCaptureSession()
fileprivate var stillImageOutput = AVCaptureStillImageOutput()
fileprivate var layer = AVCaptureVideoPreviewLayer()
fileprivate var timer: Timer?
fileprivate var label = UILabel()

override func viewDidLoad() {
super.viewDidLoad()

self.label.frame = CGRect(x: 0, y: 100, width: ScreenWidth, height: 21)
self.label.text = "等待验证"
self.label.textColor = UIColor.red
self.navigationController?.view.addSubview(self.label)

self.startSession()
}

override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
self.label.removeFromSuperview()
}

fileprivate func startSession() {
var captureDevice: AVCaptureDevice?
if let array = AVCaptureDevice.devices() {
for i in array {
let device = i as! AVCaptureDevice
if device.hasMediaType(AVMediaTypeVideo) {
if device.position == AVCaptureDevicePosition.front {
captureDevice = device
break
}
}
}
}else {
return
}
do {
let input = try AVCaptureDeviceInput.init(device: captureDevice)
let output = AVCaptureMetadataOutput()
self.session.addInput(input)
self.session.addOutput(output)

output.setMetadataObjectsDelegate(self, queue: DispatchQueue.main)
output.metadataObjectTypes = [AVMetadataObjectTypeFace]
//            output.rectOfInterest = CGRect(x: 135/ScreenHeight, y: (ScreenWidth-190)/(2*ScreenWidth), width: 240/ScreenHeight, height: 190/ScreenWidth)

self.stillImageOutput.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]
self.session.addOutput(self.stillImageOutput)

self.layer = AVCaptureVideoPreviewLayer(session: self.session)
self.layer.videoGravity = AVLayerVideoGravityResizeAspectFill
self.layer.frame = UIScreen.main.bounds

self.view.layer.addSublayer(self.layer)
self.session.startRunning()
}catch {
return
}

}

func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [Any]!, from connection: AVCaptureConnection!) {
if let meta = metadataObjects.first as? AVMetadataFaceObject {
let a = self.layer.transformedMetadataObject(for: meta) as! AVMetadataFaceObject
let faceRect = CGRect(x: a.bounds.origin.x-10, y: a.bounds.origin.y-10, width: a.bounds.size.width+20, height: a.bounds.size.height+20)
if faceRect.origin.x <= 70 && faceRect.size.width >= ScreenWidth-140 {
if self.timer == nil {
self.timer = Timer.scheduledTimer(timeInterval: 3, target: self, selector: #selector(ScanFaceViewController.isStop), userInfo: nil, repeats: false)
self.startUpdateView()
}
}
}else {
self.timer?.invalidate()
self.timer = nil
self.stopUpdateView()
}
}

fileprivate func startUpdateView() {
if self.timer != nil {
self.label.text = "验证中"
UIView.animate(withDuration: 0.2, animations: {
self.label.alpha = 0.2
}, completion: { (finish) in
UIView.animate(withDuration: 0.2, animations: {
self.label.alpha = 1
}, completion: { (finish) in
self.startUpdateView()
})
})
}
}

fileprivate func stopUpdateView() {
self.label.text = "等待验证"
self.label.alpha = 1
}

@objc fileprivate func isStop() {
self.timer?.invalidate()
self.timer = nil
self.catchImage()
self.session.stopRunning()
}

@objc fileprivate func catchImage() {
var imageConnection: AVCaptureConnection?
for c in self.stillImageOutput.connections {
let connection = c as! AVCaptureConnection
for p in connection.inputPorts {
let port = p as! AVCaptureInputPort
if port.mediaType == AVMediaTypeVideo {
imageConnection = connection
break
}
}
if let _ = imageConnection {
break
}
}
self.stillImageOutput.captureStillImageAsynchronously(from: imageConnection!, completionHandler: { (imageDataSampleBuffer, error) -> Void in
if let bu = imageDataSampleBuffer {
let imageData = AVCaptureStillImageOutput.jpegStillImageNSDataRepresentation(bu)
let facePhoto = UIImage(data: imageData!)
let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss"
self.saveImage(image: facePhoto!, saveName: "\(formatter.string(from: Date()))")
}
})
}

fileprivate func saveImage(image: UIImage, saveName: String) {
if let data = UIImageJPEGRepresentation(image, 0.8) {
let fullPath = NSHomeDirectory().appending("/Documents").appending("/\(saveName)")
NSData(data: data).write(toFile: fullPath, atomically: false)
}
}
}