How to Read a Barcode from Camera in VB .NET
In the rapidly evolving landscape of technology, barcode scanner devices have become an integral part of various industries, ranging from retail and logistics to healthcare and manufacturing. Visual Basic .NET from Microsoft, a versatile and powerful programming language, provides developers with a robust framework for creating applications that can read barcodes directly from a camera feed. This article aims to provide a comprehensive barcode reader tutorial using a camera in Visual Basic using the IronBarcode library from Iron Software.
IronBarcode library allows you to read barcode image files and also when streamed from cameras. It also supports the reading of barcodes from a PDF document. It is able to scan a maximum of one barcode at a time. The barcode type needs to be specified at the time of reading the barcode image in the VB.NET barcode reader SDK.
How to Read a Barcode from Camera in VB .NET
- Create a new VB.NET Project in Visual Studio
- Install the IronBarcode Library and apply it to your project
- Get the barcode from the camera as an image using the AForge Library
- Decode the barcode image using IronBarcode
Prerequisites
- Visual Studio: Ensure you have Visual Studio or any other VB.NET development environment installed.
- Compatible Camera: Ensure said camera is connected to your device.
- NuGet Package Manager: Make sure you can use NuGet to manage packages in your project.
Step 1: Create a New Visual Basic .NET Project in Visual Studio
Create a new VB.NET Windows Forms application (or use an existing project) where you want to host the code to read the barcode from your camera.
In the next step, you can provide the solution and project names.
Select the .NET version and click the "Create" button.
Step 2: Install the IronBarcode Library
Open your VB.NET project and install the IronBarcode library using the NuGet Package Manager Console:
Install-Package BarCode
The NuGet package can also be installed using Visual Studio's NuGet Package Manager, as shown below.
Step 3: Reading the Barcode from the Camera
To scan the feed and capture the image from the camera, we need the AForge Library. Install it as below from the NuGet package manager.
The next step is to add the PictureBox control from the ToolBox to the forms. This is used to capture the image from the camera.
Then copy the below code to the forms application and create the VB .NET barcode reader component from IronBarcode.
Imports IronBarCode
Imports AForge.Video
Imports AForge.Video.DirectShow
Public Class Form1
Private videoDevices As FilterInfoCollection
Private videoSource As VideoCaptureDevice
' Event handler for form load
Private Sub MainForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
videoDevices = New FilterInfoCollection(FilterCategory.VideoInputDevice)
If videoDevices.Count > 0 Then
videoSource = New VideoCaptureDevice(videoDevices(0).MonikerString)
AddHandler videoSource.NewFrame, AddressOf VideoSource_NewFrame
videoSource.Start()
Else
MessageBox.Show("No video devices found.")
Close()
End If
End Sub
' Event handler for capturing and processing new frame from the video source
Private Sub VideoSource_NewFrame(sender As Object, eventArgs As NewFrameEventArgs)
pictureBoxCamera.Image = DirectCast(eventArgs.Frame.Clone(), Bitmap)
' Process each frame for barcode recognition
Dim image = DirectCast(pictureBoxCamera.Image, Bitmap)
Dim result = BarcodeReader.QuicklyReadOneBarcode(image, BarcodeEncoding.QRCode Or BarcodeEncoding.Code128)
If result IsNot Nothing Then
' Barcode found, handle the new result (e.g., display the barcode value)
Dim barcodeValue As String = result.Text
ShowBarcodeResult(barcodeValue)
End If
End Sub
' Method to display the barcode result
Private Sub ShowBarcodeResult(barcodeValue As String)
' Invoke on UI thread to update UI controls
If InvokeRequired Then
Invoke(New Action(Of String)(AddressOf ShowBarcodeResult), barcodeValue)
Else
' Display the barcode value in a MessageBox or any other UI element
MessageBox.Show("Barcode Value: " & barcodeValue, "Barcode Detected")
End If
End Sub
' Event handler for form closing
Private Sub MainForm_FormClosing(sender As Object, e As FormClosingEventArgs) Handles MyBase.FormClosing
If videoSource IsNot Nothing AndAlso videoSource.IsRunning Then
videoSource.SignalToStop()
videoSource.WaitForStop()
End If
End Sub
End Class
Imports IronBarCode
Imports AForge.Video
Imports AForge.Video.DirectShow
Public Class Form1
Private videoDevices As FilterInfoCollection
Private videoSource As VideoCaptureDevice
' Event handler for form load
Private Sub MainForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
videoDevices = New FilterInfoCollection(FilterCategory.VideoInputDevice)
If videoDevices.Count > 0 Then
videoSource = New VideoCaptureDevice(videoDevices(0).MonikerString)
AddHandler videoSource.NewFrame, AddressOf VideoSource_NewFrame
videoSource.Start()
Else
MessageBox.Show("No video devices found.")
Close()
End If
End Sub
' Event handler for capturing and processing new frame from the video source
Private Sub VideoSource_NewFrame(sender As Object, eventArgs As NewFrameEventArgs)
pictureBoxCamera.Image = DirectCast(eventArgs.Frame.Clone(), Bitmap)
' Process each frame for barcode recognition
Dim image = DirectCast(pictureBoxCamera.Image, Bitmap)
Dim result = BarcodeReader.QuicklyReadOneBarcode(image, BarcodeEncoding.QRCode Or BarcodeEncoding.Code128)
If result IsNot Nothing Then
' Barcode found, handle the new result (e.g., display the barcode value)
Dim barcodeValue As String = result.Text
ShowBarcodeResult(barcodeValue)
End If
End Sub
' Method to display the barcode result
Private Sub ShowBarcodeResult(barcodeValue As String)
' Invoke on UI thread to update UI controls
If InvokeRequired Then
Invoke(New Action(Of String)(AddressOf ShowBarcodeResult), barcodeValue)
Else
' Display the barcode value in a MessageBox or any other UI element
MessageBox.Show("Barcode Value: " & barcodeValue, "Barcode Detected")
End If
End Sub
' Event handler for form closing
Private Sub MainForm_FormClosing(sender As Object, e As FormClosingEventArgs) Handles MyBase.FormClosing
If videoSource IsNot Nothing AndAlso videoSource.IsRunning Then
videoSource.SignalToStop()
videoSource.WaitForStop()
End If
End Sub
End Class
In this sample code, we have configured it to read QR codes and Code 128 barcodes. First, we use a PictureBox to capture barcode images from a webcam or any camera device by scanning the barcode. Then we create a bitmap image, which is then provided as input to the IronBarcode BarcodeReader
class. This application reads the 2D barcode from images and decodes them. If a positive result is obtained after decoding, then the result is displayed in the message box.
Licensing (Free Trial Available)
To use IronBarcode, you need to place a license key in your appsettings.json
.
{
"IronBarcode.LicenseKey": "MYLICENSE.KEY.TRIAL"
}
Provide your email ID to get a trial license, and after submitting the email ID, the key will be delivered via email.
Conclusion
Implementing barcode reading from a camera in VB.NET is a powerful feature that can enhance various applications across different industries. By leveraging libraries like IronBarcode and integrating them into your VB.NET project, you can create efficient and reliable barcode scanning applications that meet the demands of today's technology-driven world. This guide serves as a starting point, and developers can further customize and optimize the solution based on their specific requirements, barcode types, and use cases.
Frequently Asked Questions
What is the library used in VB.NET projects for reading barcodes?
IronBarcode is a library from IronSoftware that allows developers to read barcode image files and those streamed from cameras. It is used in VB.NET projects to integrate barcode reading capabilities by decoding images captured from camera feeds.
What are the prerequisites for reading barcodes from a camera in a project?
The prerequisites include having Visual Studio or another VB.NET development environment installed, a compatible camera connected to your device, and the ability to manage packages using NuGet.
How do I start a new project for barcode reading?
Start by creating a new VB.NET Windows Forms application in Visual Studio where you can host the code to read the barcode from your camera.
How can I install the barcode library in my project?
You can install the IronBarcode library using the NuGet Package Manager Console in Visual Studio with the command: Install-Package Barcode.
What is the role of the AForge library in barcode reading from a camera?
The AForge library is used to scan the feed and capture images from the camera, which can then be processed for barcode recognition.
How does the application process the captured barcode images?
The application uses a PictureBox to capture images from the camera. These images are then processed using the IronBarcode BarcodeReader class to decode and read barcodes.
What types of barcodes can be read in the project?
The sample code provided is configured to read QR codes and Code 128 barcodes, but IronBarcode supports a wide range of barcode types.
Is there a trial available for the barcode library, and how can I obtain it?
Yes, a trial is available. You can obtain a trial license key by providing your email ID on the IronSoftware website, and the key will be delivered via email.
How can I display the result of a barcode scan in an application?
Once a barcode is detected and decoded, the result can be displayed using a MessageBox or another UI element to show the barcode value.
How does the library ensure reliable barcode scanning in applications?
IronBarcode integrates seamlessly with VB.NET applications, allowing developers to leverage its efficient barcode reading capabilities to create reliable and responsive barcode scanning solutions.