iOS 人脸识别(检测)

约定不等于承诺〃 2022-09-22 13:55 287阅读 0赞

**本文用的是系统自带的人脸识别功能，跟扫二维码条形码是一样的，但是系统只能识别出这是人的脸，至于高级的判断这张脸是谁的，需要更高级的第三方库了。**

**这里是检测到有人脸，然后三秒后自动拍照并存储到本地。**

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)
            }
        }
    }

用的是Swift3.0写的，如果没更新到最新的Swift，会报错