flutter_ocr_sdk 0.4.0

A wrapper for Dynamsoft OCR SDK, detecting MRZ in passports, travel documents, and ID cards.

example/lib/main.dart

import 'dart:typed_data';

import 'package:file_selector/file_selector.dart';
import 'package:flutter/material.dart';
import 'dart:async';

import 'dart:io';

import 'package:flutter_ocr_sdk/flutter_ocr_sdk.dart';
import 'package:flutter_ocr_sdk/flutter_ocr_sdk_platform_interface.dart';
import 'package:flutter_ocr_sdk/mrz_line.dart';
import 'package:flutter_ocr_sdk/mrz_parser.dart';
import 'package:image_picker/image_picker.dart';

import 'package:flutter/foundation.dart' show kIsWeb;

import 'dart:ui' as ui;

Future<void> main() async {
  runApp(
    MaterialApp(
      title: 'MRZ OCR',
      home: Scaffold(
        appBar: AppBar(
          title: const Text("MRZ OCR"),
        ),
        body: MRZApp(),
      ),
    ),
  );
}

class MRZApp extends StatefulWidget {
  @override
  MobileState createState() => MobileState();
}

class MobileState extends State<MRZApp> {
  late FlutterOcrSdk _mrzDetector;
  final picker = ImagePicker();

  @override
  void initState() {
    super.initState();

    initSDK();
  }

  Future<void> initSDK() async {
    _mrzDetector = FlutterOcrSdk();
    int? ret = await _mrzDetector.init(
        "https://cdn.jsdelivr.net/npm/dynamsoft-label-recognizer@2.2.11/dist/",
        "DLS2eyJoYW5kc2hha2VDb2RlIjoiMjAwMDAxLTE2NDk4Mjk3OTI2MzUiLCJvcmdhbml6YXRpb25JRCI6IjIwMDAwMSIsInNlc3Npb25QYXNzd29yZCI6IndTcGR6Vm05WDJrcEQ5YUoifQ==");
    await _mrzDetector.loadModel();
  }

  void pictureScan(String source) async {
    XFile? photo;
    if (kIsWeb || Platform.isAndroid || Platform.isIOS) {
      if (source == 'camera') {
        photo = await picker.pickImage(source: ImageSource.camera);
      } else {
        photo = await picker.pickImage(source: ImageSource.gallery);
      }
    } else if (Platform.isWindows || Platform.isLinux) {
      const XTypeGroup typeGroup = XTypeGroup(
        label: 'images',
        extensions: <String>['jpg', 'png', 'bmp', 'tiff', 'pdf', 'gif'],
      );
      photo = await openFile(acceptedTypeGroups: <XTypeGroup>[typeGroup]);
    }

    if (photo == null) {
      if (!mounted) return;
      Navigator.pop(context);
      return;
    }

    String information = 'No results';

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

    // Uint8List fileBytes = await photo.readAsBytes();

    // ui.Image image = await decodeImageFromList(fileBytes);

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

    //   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();
    //       }
    //     }
    //   }
    // }

    if (!mounted) return;
    Navigator.pop(context);
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => DisplayPictureScreen(
            imagePath: photo!.path, mrzInformation: information),
      ),
    );
  }

  @override
  void dispose() {
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    double width = MediaQuery.of(context).size.width;
    double height = MediaQuery.of(context).size.height;
    double left = 5;
    double mrzHeight = 50;
    double mrzWidth = width - left * 2;
    return Scaffold(
      body: Stack(children: [
        Center(
          child: Column(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                MaterialButton(
                  textColor: Colors.white,
                  color: Colors.blue,
                  onPressed: () async {
                    showDialog(
                        context: context,
                        builder: (BuildContext context) {
                          return const Center(
                            child: CircularProgressIndicator(),
                          );
                        });
                    pictureScan('gallery');
                  },
                  child: const Text('Pick gallery image'),
                ),
                MaterialButton(
                  textColor: Colors.white,
                  color: Colors.blue,
                  onPressed: () async {
                    showDialog(
                        context: context,
                        builder: (BuildContext context) {
                          return const Center(
                            child: CircularProgressIndicator(),
                          );
                        });
                    pictureScan('camera');
                  },
                  child: const Text('Pick camera image'),
                ),
              ]),
        )
      ]),
    );
  }
}

Image getImage(String imagePath) {
  if (kIsWeb) {
    return Image.network(imagePath);
  } else {
    return Image.file(
      File(imagePath),
      fit: BoxFit.contain,
      height: double.infinity,
      width: double.infinity,
      alignment: Alignment.center,
    );
  }
}

// A widget that displays the picture taken by the user.
class DisplayPictureScreen extends StatelessWidget {
  final String imagePath;
  final String mrzInformation;

  const DisplayPictureScreen(
      {Key? key, required this.imagePath, required this.mrzInformation})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('MRZ OCR')),
      body: Stack(
        alignment: const Alignment(0.0, 0.0),
        children: [
          // Show full screen image: https://stackoverflow.com/questions/48716067/show-fullscreen-image-at-flutter

          getImage(imagePath),
          Container(
            decoration: const BoxDecoration(
              color: Colors.black45,
            ),
            child: Text(
              mrzInformation,
              style: const TextStyle(
                fontSize: 14,
                color: Colors.white,
              ),
            ),
          ),
        ],
      ),
    );
  }
}