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You are viewing a history document page of Dynamsoft Label Recognizer iOS v2.2.20.

LabelResultListener is the protocol to handle callback when label recognition results are output.

@protocol LabelResultListener
Method Description
labelResultCallback If ImageSource is correctly configured, the callback is triggered each time when label recognition results are output.


- (void)labelResultCallback:(NSInteger)frameId imageData:(iImageData *_Nonnull)imageData results:(NSArray<iDLRResult*>* _Nullable)results;


[in] frameId The ID of the frame.
[in] imageData The image data of frame.
[in] results Recognized label results of the frame.

Code Snippet

  • Objective-C
  • Swift
  1. @interface ViewController ()<LabelResultListener>
    @property (nonatomic, strong) DynamsoftLabelRecognizer *labelRecognizer;
    @property (nonatomic, strong) DynamsoftCameraEnhancer *cameraEnhancer;
    @property (nonatomic, strong) DCECameraView *dceView;
    - (void)configureDLR {
       // Setup Dynamsoft Camera Enhancer
       self.dceView = [[DCECameraView alloc] initWithFrame:self.view.bounds];
       self.cameraEnhancer = [[DynamsoftCameraEnhancer alloc] initWithView:self.dceView];
       [self.view addSubview:self.dceView];
       // Initialize Dynamsoft Label Recognizer
       recognizer = [[DynamsoftLabelRecognizer alloc] init];
       // Trigger setImageSource
       [self.labelRecognizer setImageSource:self.cameraEnhancer];
       [self.labelRecognizer setLabelResultListener:self];
       [self.cameraEnhancer open];
       [self.labelRecognizer startScanning];
    - (void)labelResultCallback:(NSInteger)frameId imageData:(iImageData *)imageData results:(NSArray<iDLRResult *> *)results {
       // Add your code to do with label recognition results
  2. class ViewController: BaseViewController, LabelResultListener {
       var labelRecognizer: DynamsoftLabelRecognizer!
       var cameraEnhancer: DynamsoftCameraEnhancer!
       var dceView: DCECameraView!
       func configureDLR() -> Void {
          // Setup Dynamsoft Camera Enhancer
          dceView = DCECameraView.init(frame: self.view.bounds)
          cameraEnhancer = DynamsoftCameraEnhancer.init(view: self.dceView)
          // Initialize Dynamsoft Label Recognizer
          let recognizer = DynamsoftLabelRecognizer()
          // Trigger setImageSource

       func labelResultCallback(_ frameId: Int, imageData: iImageData, results: [iDLRResult]?) {
          // Add your code to do with label recognition results

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Version 7.5.0

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