flutter_twain_scanner

A Flutter plugin that enables you to develop cross-platform applications for digitizing documents from TWAIN (32-bit/64-bit), WIA, SANE, ICA and eSCL scanners. The plugin offers callable methods for both open-source TWAIN (64-bit only) and the Dynamsoft Service REST API.

Dynamsoft Service REST API

By default, the REST API's host address is set to http://127.0.0.1:18622.

Method	Endpoint	Description	Parameters	Response
GET	/DWTAPI/Scanners	Get a list of scanners	None	200 OK with scanner list
POST	/DWTAPI/ScanJobs	Creates a scan job	license, device, config	201 Created with job ID
GET	/DWTAPI/ScanJobs/:id/NextDocument	Retrieves a document image	id: Job ID	200 OK with image stream
DELETE	/DWTAPI/ScanJobs/:id	Deletes a scan job	id: Job ID	200 OK

To make Dynamsoft Service work:

1. Install Dynamsoft Service.

   • Windows: Dynamsoft-Service-Setup.msi
   • macOS: Dynamsoft-Service-Setup.pkg
   • Linux:
     • Dynamsoft-Service-Setup.deb
     • Dynamsoft-Service-Setup-arm64.deb
     • Dynamsoft-Service-Setup-mips64el.deb
     • Dynamsoft-Service-Setup.rpm

2. Request a free trial license.

Dynamsoft Service Configuration

After installing the Dynamsoft Service, navigate to http://127.0.0.1:18625/ in a web browser to configure the host and port settings. The default host IP address is set to 127.0.0.1. If you wish to make the service accessible from desktop, mobile, and web applications in your office, you can update the host setting to a LAN IP address, such as 192.168.8.72.

API Usage

Open Source TWAIN (Windows 64-bit only)

• Future<List<String>> getDataSources(): Get the list of TWAIN compatible scanners.

  List<String> scanners = await _flutterTwainScannerPlugin.getDataSources();

• Future<List<String>> scanDocument(int sourceIndex): Scan documents from a selected scanner.

  int index = _scanners.indexOf(_selectedScanner!);
  List<String> documentPaths = await _flutterTwainScannerPlugin.scanDocument(index);

Dynamsoft Service (Windows, macOS, Linux, Android, iOS and Web)

• Future<List<dynamic>> getDevices(String host, [int? scannerType]): Get the list of TWAIN, WIA, and eSCL compatible scanners.

  final DynamsoftService dynamsoftService = DynamsoftService();
  String host = 'http://127.0.0.1:18622';
  final scanners = await dynamsoftService.getDevices(host, ScannerType.TWAINSCANNER | ScannerType.TWAINX64SCANNER);

• Future<void> deleteJob(String host, String jobId): Deletes a scan job based on the provided job ID.

  await dynamsoftService.deleteJob(host, jobId);

• Future<List<String>> getImageFiles(String host, String jobId, String directory): Saves images from a scan job to a directory.

  List<Uint8List> paths =
          await dynamsoftService.getImageFiles(host, jobId, './');

• Future<List<Uint8List>> getImageStreams(String host, String jobId): Retrieves image streams from a scan job.

  List<Uint8List> paths =
          await dynamsoftService.getImageStreams(host, jobId);

• Future<String> scanDocument(String host, Map<String, dynamic> parameters): Creates a new scan job using provided parameters.

  final Map<String, dynamic> parameters = {
    'license':
        'LICENSE-KEY',
    'device': devices[index]['device'],
  };
  
  parameters['config'] = {
    'IfShowUI': false,
    'PixelType': 2,
    'Resolution': 200,
    'IfFeederEnabled': false,
    'IfDuplexEnabled': false,
  };
  
  final String jobId =
        await dynamsoftService.scanDocument(host, parameters);

  The scanner parameter configuration is based on Dynamsoft Web TWAIN documentation.