MAUI User Guide for MRZ Scanner Integration
Table of Contents
- MAUI User Guide for MRZ Scanner Integration
- Table of Contents
- Supported Machine-Readable Travel Document Types
- System Requirements
- Installation
- Build Your MRZ Scanner App
- Licensing
Supported Machine-Readable Travel Document Types
The Machine Readable Travel Documents (MRTD) standard specified by the International Civil Aviation Organization (ICAO) defines how to encode information for optical character recognition on official travel documents.
Currently, the SDK supports three types of MRTD:
Note: If you need support for other types of MRTDs, our SDK can be easily customized. Please contact support@dynamsoft.com.
ID (TD1 Size)
The MRZ (Machine Readable Zone) in TD1 format consists of 3 lines, each containing 30 characters.
ID (TD2 Size)
The MRZ (Machine Readable Zone) in TD2 format consists of 2 lines, with each line containing 36 characters.
Passport (TD3 Size)
The MRZ (Machine Readable Zone) in TD3 format consists of 2 lines, with each line containing 44 characters.
System Requirements
.Net
- .NET 7.0 and .NET 8.0.
Android
- Supported OS: Android 5.0 (API Level 21) or higher.
- Supported ABI: armeabi-v7a, arm64-v8a, x86 and x86_64.
- Development Environment: Visual Studio 2022 recommended.
- JDK: 1.8+
iOS
- Supported OS: iOS 11.0 or higher.
- Supported ABI: arm64 and x86_64.
- Development Environment: Visual Studio 2022 for Mac and Xcode 14.3+ recommended.
Installation
Visual Studio for Mac
In the NuGet Package Manager>Manage Packages for Solution of your project, search for Dynamsoft.CaptureVisionBundle.Maui and Dynamsoft.MRZ.Maui. Select it and click install.
Visual Studio for Windows
You have to Add the library via the project file and do some additional steps to complete the installation.
-
Add the library in the project file:
<Project Sdk="Microsoft.NET.Sdk"> ... <ItemGroup> ... <PackageReference Include="Dynamsoft.CaptureVisionBundle.Maui" Version="2.4.2000" /> <PackageReference Include="Dynamsoft.MRZ.Maui" Version="3.4.200" /> </ItemGroup> </Project> -
Open the Package Manager Console and run the following commands:
dotnet build
Note:
- Windows system have a limitation of 260 characters in the path. If you don’t use console to install the package, you will receive error “Could not find a part of the path ‘C:\Users\admin.nuget\packages\dynamsoft.imageprocessing.ios\2.4.200\lib\net7.0-ios16.1\Dynamsoft.ImageProcessing.iOS.resources\DynamsoftImageProcessing.xcframework\ios-arm64\dSYMs\DynamsoftImageProcessing.framework.dSYM\Contents\Resources\DWARF\DynamsoftImageProcessing’”
- The library only support Android & iOS platform. Be sure that you remove the other platforms like Windows, maccatalyst, etc.
Build Your MRZ Scanner App
Now you will learn how to create a SimpleMRZScanner using Dynamsoft Capture Vision MAUI SDK.
Note:
- You can get the similar source code of the SimpleMRZScanner app from the following link
- C#.
Set up Development Environment
If you are a beginner with MAUI, please follow the guide on the .Net MAUI official website to set up the development environment.
Initialize the Project
Visual Studio
- Open the Visual Studio and select Create a new project.
- Select .Net MAUI App and click Next.
- Name the project SimpleMRZScanner. Select a location for the project and click Next.
- Select .Net 7.0 and click Create.
Visual Studio for Mac
- Open Visual Studio and select New.
- Select Multiplatform > App > .Net MAUI App > C# and click Continue.
- Select .Net 7.0 and click Continue.
- Name the project SimpleMRZScanner and select a location, click Create.
Include the Library
Please view the installation section on how to add the library.
Initialize MauiProgram
In MauiProgram.cs, add a custom handler for the CameraView control. Specifically, it maps the CameraView type to the CameraViewHandler type.
namespace SimpleMRZScanner;
using Microsoft.Extensions.Logging;
using Dynamsoft.CameraEnhancer.Maui;
using Dynamsoft.CameraEnhancer.Maui.Handlers;
public static class MauiProgram
{
public static MauiApp CreateMauiApp()
{
var builder = MauiApp.CreateBuilder();
builder
.UseMauiApp<App>()
.ConfigureFonts(fonts =>
{
fonts.AddFont("OpenSans-Regular.ttf", "OpenSansRegular");
fonts.AddFont("OpenSans-Semibold.ttf", "OpenSansSemibold");
})
.ConfigureMauiHandlers(handlers =>
{
handlers.AddHandler(typeof(CameraView), typeof(CameraViewHandler));
});
#if DEBUG
builder.Logging.AddDebug();
#endif
return builder.Build();
}
}
License Activation
The Dynamsoft Capture Vision SDK needs a valid license to work. Please refer to the Licensing section for more info on how to obtain a license.
Go to MainPage.xaml.cs. Add the following code to activate the license:
namespace SimpleMRZScanner;
using Dynamsoft.License.Maui;
using System.Diagnostics;
public partial class MainPage : ContentPage, ILicenseVerificationListener
{
public MainPage()
{
InitializeComponent();
LicenseManager.InitLicense("DLS2eyJvcmdhbml6YXRpb25JRCI6IjIwMDAwMSJ9", this);
}
public void OnLicenseVerified(bool isSuccess, string message)
{
if (!isSuccess)
{
Debug.WriteLine(message);
}
}
}
Initialize the Capture Vision SDK
In the MainPage.xaml.cs, add the following code to initialize the Capture Vision SDK:
......
using Dynamsoft.CaptureVisionRouter.Maui;
using Dynamsoft.CameraEnhancer.Maui;
using Dynamsoft.Core.Maui;
using Dynamsoft.Utility.Maui;
public partial class MainPage : ContentPage, ILicenseVerificationListener, ICapturedResultReceiver
{
CameraEnhancer enhancer;
CaptureVisionRouter router;
public MainPage()
{
......
// Create an instance of CameraEnhancer
enhancer = new CameraEnhancer();
// Create an instance of CaptureVisionRouter
router = new CaptureVisionRouter();
// Bind the router with the created CameraEnhancer
router.SetInput(enhancer);
// Add the result receiver to receive the textline result and parsed MRZ result
router.AddResultReceiver(this);
// Add the result filter to verify the result across multiple frames
var filter = new MultiFrameResultCrossFilter();
filter.EnableResultCrossVerification(EnumCapturedResultItemType.CRIT_TEXT_LINE, true);
router.AddResultFilter(filter);
}
}
Add the CameraView control in the Main Page
In the MainPage.xaml, add a CameraView control:
<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:controls="clr-namespace:Dynamsoft.CameraEnhancer.Maui;assembly=Dynamsoft.CaptureVisionRouter.Maui"
x:Class="SimpleMRZScanner.MainPage"
Title="MainPage">
<AbsoluteLayout>
<controls:CameraView x:Name="cameraView"
AbsoluteLayout.LayoutBounds="0,0,1,1"
AbsoluteLayout.LayoutFlags="All"/>
</AbsoluteLayout>
</ContentPage>
Open the Camera and Start Reading MRZ
In this section, we are going to add code to start reading MRZ in the MainPage.xaml.cs.
......
public partial class MainPage : ContentPage, ILicenseVerificationListener, ICapturedResultReceiver, ICompletionListener
{
......
protected override void OnHandlerChanged()
{
base.OnHandlerChanged();
if (this.Handler != null)
{
enhancer.SetCameraView(cameraView);
}
}
protected override async void OnAppearing()
{
base.OnAppearing();
// Request camera permission
await Permissions.RequestAsync<Permissions.Camera>();
// Open camera
enhancer?.Open();
// Start reading MRZ
router?.StartCapturing("ReadPassportAndId", this);
}
protected override void OnDisappearing()
{
base.OnDisappearing();
// Close camera
enhancer?.Close();
// Stop reading MRZ
router?.StopCapturing();
}
// It is called when StartCapturing is successful
public void OnSuccess()
{
Debug.WriteLine("Success");
}
// It is called when StartCapturing is failed
public void OnFailure(int errorCode, string errorMessage)
{
Debug.WriteLine(errorMessage);
}
}
Open the Info.plist file under the Platforms/iOS/ folder (Open with XML Text Editor). Add the following lines to request camera permission on iOS platform:
<key>NSCameraUsageDescription</key>
<string>The sample needs to access your camera.</string>
Obtaining Recognized Text Lines and Parsed MRZ
In MainPage.xaml.cs, implement ICapturedResultReceiver to receive recognized text lines and parsed MRZ result in OnRecognizedTextLinesReceived and OnParsedResultsReceived callback function.
......
using Dynamsoft.LabelRecognizer.Maui;
using Dynamsoft.CodeParser.Maui;
public partial class MainPage : ContentPage, ILicenseVerificationListener, ICapturedResultReceiver, ICompletionListener
{
......
public void OnRecognizedTextLinesReceived(RecognizedTextLinesResult result)
{
if (result.Items == null)
{
return;
}
List<TextLineResultItem> items = result.Items;
items.ForEach(item =>
{
text += item.Text + "\n\n";
});
}
public void OnParsedResultsReceived(ParsedResult result)
{
if (result.Items == null)
return;
if (result.Items.Count() == 0)
{
if (text.Length != 0)
{
Debug.WriteLine("Error: Failed to parse the MRZ text: " + text);
}
}
else
{
Dictionary<string, ParsedField> entry = result.Items[0].ParsedFields;
string number = entry.ContainsKey("passportNumber") ? entry["passportNumber"].Value : entry.ContainsKey("documentNumber") ? entry["documentNumber"].Value : "";
string firstName = entry.ContainsKey("secondaryIdentifier") ? " " + entry["secondaryIdentifier"].Value : "";
string lastName = entry.TryGetValue("primaryIdentifier", out var identifier) ? identifier.Value ?? "" : "";
string name = lastName + firstName;
// Process the results according to your needs.
Debug.WriteLine("MRZ Result:\n" + "Number:" + number + "\nName:" + name);
}
}
}
Run the Project
Select your device and run the project.
You can get the similar source code of the SimpleMRZScanner app from the following link:
- C#.
Note: If you are running Android only on Visual Studio Windows, please manually exclude iOS and Windows platforms. Otherwise, the Visual Studio will report type or namespace not found errors.
Licensing
- A one-day trial license is available by default for every new device to try Dynamsoft Capture Vision SDK.
- You can request a 30-day trial license via the Request a Trial License link.
- Contact us to purchase a full license.
Yes
No