barcode_scanner_kit 1.0.1

Barcode scanner

Google's ML Barcode Scanner Flutter Plugin

A Flutter plugin to use Google's standalone ML Kit for Android and iOS.

Features

Vision

Feature	Android	iOS
Barcode Scanning	✅	✅

Requirements

iOS

• Minimum iOS Deployment Target: 10.0
• Xcode 12 or newer
• Swift 5
• ML Kit only supports 64-bit architectures (x86_64 and arm64). Check this list to see if your device has the required device capabilities.

Since ML Kit does not support 32-bit architectures (i386 and armv7) (Read mode), you need to exclude amrv7 architectures in Xcode in order to run flutter build ios or flutter build ipa.

Go to Project > Runner > Building Settings > Excluded Architectures > Any SDK > armv7

Then your Podfile should look like this:

# add this line:
$iOSVersion = '10.0'

post_install do |installer|
  # add these lines:
  installer.pods_project.build_configurations.each do |config|
    config.build_settings["EXCLUDED_ARCHS[sdk=*]"] = "armv7"
    config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = $iOSVersion
  end
  
  installer.pods_project.targets.each do |target|
    flutter_additional_ios_build_settings(target)
    
    # add these lines:
    target.build_configurations.each do |config|
      if Gem::Version.new($iOSVersion) > Gem::Version.new(config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'])
        config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = $iOSVersion
      end
    end
    
  end
end

Notice that the minimum IPHONEOS_DEPLOYMENT_TARGET is 10.0, you can set it to something newer but not older.

Android

• minSdkVersion: 21
• targetSdkVersion: 29

Usage

Add this plugin as dependency in your pubspec.yaml.

• In your project-level build.gradle file, make sure to include Google's Maven repository in both your buildscript and allprojects sections(for all api's).

  <meta-data
          android:name="com.google.mlkit.vision.DEPENDENCIES"
          android:value="ica" />
      <!-- To use multiple models: android:value="ica,model2,model3" -->
  

  Use these options:

  • ocr - Barcode Scanning

1. Create an InputImage

From path:

final inputImage = InputImage.fromFilePath(filePath);

From file:

final inputImage = InputImage.fromFile(file);

From bytes:

final inputImage = InputImage.fromBytes(bytes: bytes, inputImageData: inputImageData);

From CameraImage (if you are using the camera plugin):

final camera; // your camera instance
final WriteBuffer allBytes = WriteBuffer();
for (Plane plane in cameraImage.planes) {
  allBytes.putUint8List(plane.bytes);
}
final bytes = allBytes.done().buffer.asUint8List();

final Size imageSize = Size(cameraImage.width.toDouble(), cameraImage.height.toDouble());

final InputImageRotation imageRotation =
    InputImageRotationMethods.fromRawValue(camera.sensorOrientation) ??
        InputImageRotation.Rotation_0deg;

final InputImageFormat inputImageFormat =
    InputImageFormatMethods.fromRawValue(cameraImage.format.raw) ??
        InputImageFormat.NV21;

final planeData = cameraImage.planes.map(
  (Plane plane) {
    return InputImagePlaneMetadata(
      bytesPerRow: plane.bytesPerRow,
      height: plane.height,
      width: plane.width,
    );
  },
).toList();

final inputImageData = InputImageData(
  size: imageSize,
  imageRotation: imageRotation,
  inputImageFormat: inputImageFormat,
  planeData: planeData,
);

final inputImage = InputImage.fromBytes(bytes: bytes, inputImageData: inputImageData);

2. Create an instance of detector

// vision
final barcodeScanner = GoogleMlKit.vision.barcodeScanner();

3. Call the corresponding method

// vision
final List<Barcode> barcodes = await barcodeScanner.processImage(inputImage);

4. Extract data from response.

a. Extract barcodes.

for (Barcode barcode in barcodes) {
  final BarcodeType type = barcode.type;
  final Rect boundingBox = barcode.value.boundingBox;
  final String displayValue = barcode.value.displayValue;
  final String rawValue = barcode.value.rawValue;

  // See API reference for complete list of supported types
  switch (type) {
    case BarcodeType.wifi:
      BarcodeWifi barcodeWifi = barcode.value;
      break;
    case BarcodeValueType.url:
      BarcodeUrl barcodeUrl = barcode.value;
      break;
  }
}

5. Release resources with close().

// vision
barcodeScanner.close();

Android

To reduce the apk size read more about it in issue #26. Also look at this.

iOS

If you are using this plugin in your app and any other plugin that requires Firebase, there is a known issues you will encounter a dependency error when running pod install. To read more about it go to issue #27.

License

MIT