Flutter MRZ SDK

A wrapper for Dynamsoft Label Recognizer v2.x with MRZ detection model. It helps developers build Flutter applications to detect machine-readable zones (MRZ) in passports, travel documents, and ID cards.

License Key

To use the SDK, you need a license key for Dynamsoft Label Recognizer. Make sure to get your trial or commercial license before using the library.

Try Flutter MRZ Detection Example

cd example
flutter run # for Android
flutter run -d chrome # for Web
flutter run -d windows # for Windows

Supported Platforms

• Android
• Web
• Windows
• Linux
• iOS

Installation

Add flutter_ocr_sdk as a dependency in your pubspec.yaml file.

dependencies:
    ...
    flutter_ocr_sdk:

Additional Step for Web

To support web functionality, include the JavaScript library of Dynamsoft Label Recognizer in your index.html file:

<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/dlr.js"></script>

API Compatibility

Methods	Android	iOS	Windows	Linux	macOS	Web
Future<int?> init(String key)	✔️	✔️	✔️	✔️	✔️	✔️
Future<int?> loadModel()	✔️	✔️	✔️	✔️	✔️	✔️
Future<List<List<MrzLine>>?> recognizeByFile(String filename)	✔️	✔️	✔️	✔️	✔️	✔️
Future<List<List<MrzLine>>?> recognizeByBuffer(Uint8List bytes, int width, int height, int stride, int format)	✔️	✔️	✔️	✔️	✔️	✔️

Usage

• Initialize the MRZ detector with a valid license key:

  FlutterOcrSdk _mrzDetector = FlutterOcrSdk();
  int? ret = await _mrzDetector.init( "DLS2eyJoYW5kc2hha2VDb2RlIjoiMjAwMDAxLTE2NDk4Mjk3OTI2MzUiLCJvcmdhbml6YXRpb25JRCI6IjIwMDAwMSIsInNlc3Npb25QYXNzd29yZCI6IndTcGR6Vm05WDJrcEQ5YUoifQ==");

• Load the MRZ detection model:

  await _mrzDetector.loadModel();

• Recognize MRZ from an image file:

  List<List<MrzLine>>? results = await _mrzDetector.recognizeByFile(photo.path);

• Recognize MRZ from an image buffer:

  ui.Image image = await decodeImageFromList(fileBytes);
  
  ByteData? byteData =
      await image.toByteData(format: ui.ImageByteFormat.rawRgba);
  
  List<List<MrzLine>>? results = await _mrzDetector.recognizeByBuffer(
        byteData.buffer.asUint8List(),
        image.width,
        image.height,
        byteData.lengthInBytes ~/ image.height,
        ImagePixelFormat.IPF_ARGB_8888.index);

• Parse MRZ information:

  String information = '';
  if (results != null && results.isNotEmpty) {
      for (List<MrzLine> area in results) {
          if (area.length == 2) {
          information =
              MRZ.parseTwoLines(area[0].text, area[1].text).toString();
          } else if (area.length == 3) {
          information = MRZ
              .parseThreeLines(area[0].text, area[1].text, area[2].text)
              .toString();
          }
      }
  }