React Native module to auto scan documents (Android only)

Live document detection library. Returns either a URI of the captured image, allowing you to easily store it or use it as you wish !

Features:

• Live detection
• Perspective correction and image crop
• Flash

Get started

npm install --save react-native-documentscanner-android

In MainApplication.java, add this Line import com.documentscanner.DocumentScannerPackage; at the top of file,

@Override
protected  List<ReactPackage> getPackages() {
  return Arrays.<ReactPackage>asList(
    new  MainReactPackage(),
    new  DocumentScannerPackage() <--- this  line,
    ...
  );
}

IMPORTANT - Go to folder app/settings.gradle and add

include ':react-native-documentscanner-android'
project(':react-native-documentscanner-android').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-documentscanner-android/android')

Add this (don't forget)

include ':openCVLibrary310'
project(':openCVLibrary310').projectDir = new File(rootProject.projectDir,'../node_modules/react-native-documentscanner-android/android/openCVLibrary310')

In android/app/src/main/AndroidManifest.xml

Change manifest header to avoid "Manifest merger error". After you add xmlns:tools="http://schemas.android.com/tools" should look like this:

<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.<yourAppName>" xmlns:tools="http://schemas.android.com/tools">

Add tools:replace="android:allowBackup" in <application tag. It should look like this:

<application tools:replace="android:allowBackup" android:name=".MainApplication" android:label="@string/app_name" android:icon="@mipmap/ic_launcher" android:allowBackup="false" android:theme="@style/AppTheme">

Add Camera permissions request:

<uses-permission android:name="android.permission.CAMERA" />

Add this to android/app/build.gradle (dependencies section)

implementation project(':react-native-documentscanner-android')

Usage

import DocumentScanner from 'react-native-documentscanner-android';

class YourComponent extends Component {
  render() {
    return (
      <View>
        <DocumentScanner
          onPictureTaken={data => {
            console.log(data.path);
          }}
          enableTorch={false}
          detectionCountBeforeCapture={5}
        />
      </View>
    );
  }
}

Properties

Props	Default	Type	Description
manualOnly	false	bool	if true, auto-detect is disabled
enableTorch	false	bool	Allows to active or deactivate flash during document detection
detectionCountBeforeCapture	15	number	Number of correct rectangle to detect before capture document
brightness	10	number	This property only work to enhance document at the save moment
contrast	1	number	This property only work to enhance document at the save moment
noGrayScale	false	bool	Currently this module saves pictures only in gray scale, this property adds the option to disable gray scale

Manual capture

• Get the component ref

<DocumentScanner ref={(ref) => this.scanner = ref} />

• Then

this.scanner.capture();

Returned Image

Prop	Params	Type	Description
onPictureTaken	data	object	Returns an image in a object { path: ('imageUri')}
onProcessing	data	object	Returns an object `{processing: (true

The images are saved in Documents folder.

Todo

• Pass overlay color dynamically
• Pass contrast and brightness to preview
• Use front cam
• Use base64

Contributors are welcome !!

Inspired in android project

• https://github.com/ctodobom/OpenNoteScanner
• https://github.com/Michaelvilleneuve/react-native-document-scanner