How to acquire black-white images from WIA scanner?
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If you want to acquire black-white images from WIA scanner, you should set the scan image pixel type (using
WiaDevice.ScanImagePixelType property) to the
WiaImagePixelType.BlackWhite value.
Supported scan image pixel types can be obtained using
WiaDevice.GetSupportedImagePixelTypes method.
Here is an example that demonstrates how to acquire black-white images from WIA device:
/// <summary>
/// Acquires black-white images from WIA image scanner.
/// </summary>
public void AcquireBlackWhiteImageFromWiaDevice()
{
// create WIA device manager
using (Vintasoft.WiaImageScanning.WiaDeviceManager deviceManager = new Vintasoft.WiaImageScanning.WiaDeviceManager())
{
// open WIA device manager
deviceManager.Open();
// get count of WIA devices
int deviceCount = deviceManager.Devices.Count;
if (deviceCount == 0)
{
System.Console.WriteLine("Devices are not found.");
return;
}
// select the first WIA device
Vintasoft.WiaImageScanning.WiaDevice device = deviceManager.Devices[0];
// open WIA device
device.Open();
// get names of supported scan image pixel types
Vintasoft.WiaImageScanning.WiaImagePixelType[] supportedImagePixelTypes = device.GetSupportedImagePixelTypes();
foreach (Vintasoft.WiaImageScanning.WiaImagePixelType imagePixelType in supportedImagePixelTypes)
{
if (imagePixelType == Vintasoft.WiaImageScanning.WiaImagePixelType.BlackWhite)
{
// specify that black-white images must be acquired from WIA device
device.ScanImagePixelType = imagePixelType;
break;
}
}
Vintasoft.WiaImageScanning.WiaAcquiredImage acquiredImage;
do
{
try
{
// acquire image from WIA device
acquiredImage = device.AcquireImageSync();
// if image is received
if (acquiredImage != null)
{
System.Console.WriteLine("Image is acquired.");
}
// if image is not received
else
{
System.Console.WriteLine("Scan is completed.");
break;
}
}
catch (System.Exception ex)
{
System.Console.WriteLine(string.Format("Scan is failed: {0}", ex.Message));
break;
}
}
// while image is acquired
while (acquiredImage != null);
// close WIA device
device.Close();
// close WIA device manager
deviceManager.Close();
}
System.Console.ReadLine();
}
''' <summary>
''' Acquires black-white images from WIA device.
''' </summary>
Public Sub AcquireBlackWhiteImageFromWiaDevice()
' create WIA device manager
Using deviceManager As New Vintasoft.WiaImageScanning.WiaDeviceManager()
' open WIA device manager
deviceManager.Open()
' get count of WIA devices
Dim deviceCount As Integer = deviceManager.Devices.Count
If deviceCount = 0 Then
System.Console.WriteLine("Devices are not found.")
Return
End If
' select the first WIA device
Dim device As Vintasoft.WiaImageScanning.WiaDevice = deviceManager.Devices(0)
' open WIA device
device.Open()
' get names of supported scan modes
Dim supportedScanImagePixelTypes As Vintasoft.WiaImageScanning.WiaImagePixelType() = device.GetSupportedImagePixelTypes()
For Each imagePixelType As Vintasoft.WiaImageScanning.WiaImagePixelType In supportedScanImagePixelTypes
If imagePixelType = Vintasoft.WiaImageScanning.WiaImagePixelType.BlackWhite Then
' specify that black-white images must be acquired from WIA device
device.ScanImagePixelType = imagePixelType
Exit For
End If
Next
Dim acquiredImage As Vintasoft.WiaImageScanning.WiaAcquiredImage
Do
Try
' acquire image from WIA device
acquiredImage = device.AcquireImageSync()
' if image is received
If acquiredImage IsNot Nothing Then
System.Console.WriteLine("Image is acquired.")
Else
' if image is not received
System.Console.WriteLine("Scan is completed.")
Exit Try
End If
Catch ex As System.Exception
System.Console.WriteLine(String.Format("Scan is failed: {0}", ex.Message))
Exit Try
End Try
' while image is acquired
Loop While acquiredImage IsNot Nothing
' close WIA device
device.Close()
' close WIA device manager
deviceManager.Close()
End Using
System.Console.ReadLine()
End Sub