Microblink：成功读取一张图片

Question

我要求 Microblink 读卡器查看卡片的照片，而不是使用相机。 我已经尝试过万事达卡的纵向和横向版本。 这就是我声明主要变量的方式：

let blinkCardRecognizer = MBCBlinkCardRecognizer()
var recognizerList = [MBCRecognizer]()

lazy var recognizerCollection: MBCRecognizerCollection = {
    blinkCardRecognizer.extractCvv = false
    blinkCardRecognizer.extractIban = false
    blinkCardRecognizer.extractExpiryDate = false

    recognizerList.append(blinkCardRecognizer)
    return MBCRecognizerCollection(recognizers: recognizerList)
}()
lazy var recognizerRunner: MBCRecognizerRunner = {
    MBCRecognizerRunner(recognizerCollection: recognizerCollection)
}()

我已经宣布了这两个代表：

MBCBlinkCardOverlayViewControllerDelegate, MBCScanningRecognizerRunnerDelegate

在我得到我的 UIImage 后，我称之为 function：

func prepareToReadImage(_ theImage: UIImage?) {
    recognizerRunner.scanningRecognizerRunnerDelegate = self
    
    var image: MBCImage? = nil
    if let anImage = theImage {
        image = MBCImage(uiImage: anImage)
    }
    image?.cameraFrame = true
    image?.orientation = MBCProcessingOrientation.down
    let _serialQueue = DispatchQueue(label: "com.microblink.DirectAPI-sample-swift")
    _serialQueue.async(execute: {() -> Void in
        self.recognizerRunner.processImage(image!)
    })
}

这是我的委托回调。 每次，我的状态都是.empty ：

func recognizerRunner(_ recognizerRunner: MBCRecognizerRunner, didFinishScanningWith state: MBCRecognizerResultState) {
    if state == .valid { // values: .empty, .uncertain, .valid, .stageValid
        let result = blinkCardRecognizer.result
        
        DispatchQueue.main.async(execute: {() -> Void in
            print (result.owner)
            print (result.cardNumber)
            print (result.cardNumberPrefix)
        })
    }
}

为什么我没有收到.valid回复？ 此外，这看起来像是提取卡详细信息的正确方法吗，一次（如果以及何时）我这样做？ 谢谢！

Answer 1

这个问题与这里的问题有关吗？

如果是这样，我还可以提出以下建议：您可以添加一个调用图像选择器的函数（我使用设备相机作为源类型）：

private func openImagePicker() {
        let imagePicker = UIImagePickerController()
        imagePicker.sourceType = .camera
        imagePicker.cameraDevice = .rear

        addOverlayLabel(toImagePicker: imagePicker)
        
        // Displays a control that allows the user to choose only photos
        imagePicker.mediaTypes = [kUTTypeImage as String]
        
        // Hides the controls for moving & scaling pictures, or for trimming movies.
        imagePicker.allowsEditing = false
        
        // Shows default camera control overlay over camera preview.
        imagePicker.showsCameraControls = true
        
        // set delegate
        imagePicker.delegate = self
        present(imagePicker, animated: true) {() -> Void in }
        imagePickerController = imagePicker
    }

在func recognizerRunner RecognizerRunner 中，您可以放置 state 无效时要调用的 func，如下所示：

extension ViewController: MBCScanningRecognizerRunnerDelegate {

func recognizerRunner(_ recognizerRunner: MBCRecognizerRunner, didFinishScanningWith state: MBCRecognizerResultState) {
    DispatchQueue.main.async(execute: {() -> Void in
        if state != .valid {
            self.openImagePicker()
            return
        }
        
        print(state.rawValue)
        let result = self.blinkCardRecognizer.result

        print("Owner: \(result.owner)")
        print("Card number: \(result.cardNumber)")
        print("Card number prefix: \(result.cardNumberPrefix)")
        
    })
  }
}

如果 state 无效，这将使您有机会重新拍摄图像。

还要问，您将prepareToReadImage放在哪里？

您需要将它放在func imagePickerController中，如下所示：

extension ViewController: UIImagePickerControllerDelegate {

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
    let mediaType = info[UIImagePickerController.InfoKey.mediaType] as? String
    
    if CFStringCompare(mediaType as CFString?, kUTTypeImage, CFStringCompareFlags(rawValue: 9)) == .compareEqualTo {
        let originalImage = info[UIImagePickerController.InfoKey.originalImage] as? UIImage
        prepareToReadImage(originalImage)
    }
    
    picker.dismiss(animated: true, completion: nil)
}

func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
    serialQueue.async {
        self.recognizerRunner?.resetState()
    }

    dismiss(animated: true, completion: nil)

  }
}

最后，确保在开始扫描过程之前放置识别器的设置。

我添加了func setupRecognizerRunner ，在这里我定义了你在代码块中所做的一切：

    private func setupRecognizerRunner() {

    blinkCardRecognizer = MBCBlinkCardRecognizer()
    var recognizers = [MBCRecognizer]()
    
    blinkCardRecognizer.extractCvv = false
    blinkCardRecognizer.extractIban = false
    blinkCardRecognizer.extractExpiryDate = false
    
    recognizers.append(blinkCardRecognizer)
    let recognizerCollection = MBCRecognizerCollection(recognizers: recognizers)
    recognizerRunner = MBCRecognizerRunner(recognizerCollection: recognizerCollection)
    
    recognizerRunner?.scanningRecognizerRunnerDelegate = self
}

在加载许可证密钥方法后，我将它放在viewDidLoad()中。

Answer 2

删除以下行使我能够获得.valid响应：

image?.cameraFrame = true