利用AVFoundation框架比第三方框架識別二維碼更快速,并且第三方框架不支持64位,本篇文章使用AVFoundation框架來完成二維碼讀取

二維碼的讀取

1.創建一個捕捉會話

let session = AVCaptureSession()

2.設置輸入設備

let device = AVCaptureDevice.defaultDeviceWithMediaType(AVMediaTypeVideo)
guard let deviceInput = try? AVCaptureDeviceInput(device: device) else {
            print("沒有獲取到輸入設備")
            return
        }
session.addInput(deviceInput)

3.設置輸出設備和代理

let output = AVCaptureMetadataOutput()
output.setMetadataObjectsDelegate(self, queue: dispatch_get_main_queue())
session.addOutput(output)
output.metadataObjectTypes = output.availableMetadataObjectTypes

4.設置掃描范圍為掃描框內,注意,設置范圍的x,y軸是于iOS的x,y軸相反的

let rect = UIScreen.mainScreen().bounds
// containerView是掃描框控件
let containerRect = containerView.frame
output.rectOfInterest = CGRect(x: containerRect.origin.y / rect.size.height , y: containerRect.origin.x / rect.size.width, width: containerRect.size.height / rect.size.height, height: containerRect.size.width / rect.size.width)

5.添加預覽圖層并開始掃描

let previewLayer = AVCaptureVideoPreviewLayer(session: session)
previewLayer.frame = UIScreen.mainScreen().bounds
view.layer.insertSublayer(previewLayer, atIndex: 0)
self.previewLayer = previewLayer
       
session.startRunning()

6.在代理方法中獲得掃描的數據并設置將獲得的數據顯示出來

func captureOutput(captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [AnyObject]!, fromConnection connection: AVCaptureConnection!)

從相冊讀取二維碼

1.創建照片源

        if !UIImagePickerController.isSourceTypeAvailable(.PhotoLibrary) {
            print("照片庫不可用")
            return
        }
        
        // 創建選擇照片的控制器
        let ipc = UIImagePickerController()
        
        // 設置照片源
        ipc.sourceType = .PhotoLibrary
        
        // 設置代理
        ipc.delegate = self
        
        // 彈出控制器
        presentViewController(ipc, animated: true, completion: nil)

2.在代理方法中拿到照片并讀取

func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
        // 拿到圖片
        guard let image = info[UIImagePickerControllerOriginalImage] as? UIImage else {
            print("沒有獲取到照片")
            return
        }

        // 創建掃描器
        let detector = CIDetector(ofType: CIDetectorTypeQRCode, context: nil, options: nil)
        
        // 掃描結果
        guard let ciImage = CIImage(image: image) else {
            print("轉ciImage失敗")
            return
        }

        let features = detector.featuresInImage(ciImage)

        // 遍歷掃描結果
        for f in features {
            guard let feature = f as? CIQRCodeFeature else {
                continue
            }
            
            print(feature.messageString)
        }

    }

生成二維碼,并且在二維碼中心畫上頭像

override func viewDidLoad() {
        super.viewDidLoad()
        
        // 創建濾鏡
        let filter = CIFilter(name: "CIQRCodeGenerator")
        
        // 恢復默認設置
        filter?.setDefaults()
        
        // 設置數據
        let qrcodeInfo = "http://www.lxweimin.com/users/d4396e83f3b4/latest_articles"
        guard let qrcodeInfoData = qrcodeInfo.dataUsingEncoding(NSUTF8StringEncoding) else {
            return
        }
        filter?.setValue(qrcodeInfoData, forKeyPath: "inputMessage")
        
        // 獲取生成的圖片
        guard let outputImage = filter?.outputImage else {
            return
        }
        
        // 設置圖片
        let image = scaleImage(outputImage)
        
        // 在二維碼中畫上頭像
        qrcodeView.image = drawIconView(image, iconName: "111")
    }
    
    private func drawIconView(image : UIImage, iconName : String) -> UIImage {
        // 開啟圖片上下文
        UIGraphicsBeginImageContext(image.size)
        
        // 將圖片畫到上下文中
        image.drawInRect(CGRect(origin: CGPointZero, size: image.size))
        
        // 根據圖標名稱生成圖片,并且將圖片畫到上下文中
        let iconImage = UIImage(named: iconName)
        let width : CGFloat = 60
        let height : CGFloat = 60
        let x = (image.size.width - width) * 0.5
        let y = (image.size.height - height) * 0.5
        iconImage?.drawInRect(CGRect(x: x, y: y, width: width, height: height))
        
        // 獲取圖片
        let drawImage = UIGraphicsGetImageFromCurrentImageContext()
        
        // 關閉上下文
        UIGraphicsEndImageContext()
        
        return drawImage
    }
    // 放大生成的二維碼
    private func scaleImage(ciImage : CIImage) -> UIImage {
        // 創建放大的系數
        let tranform = CGAffineTransformMakeScale(10, 10)
        
        // 根據放大系數放大的圖片
        let newImage = ciImage.imageByApplyingTransform(tranform)
        
        // 返回生成好的圖片
        return UIImage(CIImage: newImage)
    }