VintaSoft Twain .NET SDK v10.2
Threshold Property (Device)
Example 




Vintasoft.WpfTwain Namespace > Device Class : Threshold Property
Gets or sets the threshold of black-white images for current scan session.
Syntax
'Declaration
 
Public Property Threshold As Single
'Usage
 
Dim instance As Device
Dim value As Single
 
instance.Threshold = value
 
value = instance.Threshold
public float Threshold {get; set;}
public: __property float get_Threshold();
public: __property void set_Threshold( 
   float value
);
public:
property float Threshold {
   float get();
   void set (    float value);
}
Exceptions
ExceptionDescription
Thrown if device is in wrong state.
Thrown if device does not support capability.
Thrown if the .NET debugger is used and the function evaluation requires all threads to run.
Remarks
Call this property only when device is opened (State == DeviceState.Opened).

Supported values of brightness can be received by the GetSupportedThresholdValues method.
Example
This example shows how to acquire black-white images from the device.
Public Sub ScanBlackWhiteImageWithBitDepthReductionMode(ByVal device As Device)
    device.ShowUI = False
    device.DisableAfterAcquire = True
            
    device.Open()
    device.PixelType = PixelType.BW
    device.PixelFlavor = PixelFlavor.Chocolate
    device.BitDepthReductionMode = BitDepthReductionMode.Threshold
    device.Threshold = 128
    device.UnitOfMeasure = UnitOfMeasure.Inches
    device.Resolution = New Resolution(200.0F, 200.0F)
            
    device.Acquire()
End Sub
public void ScanBlackWhiteImageWithBitDepthReductionMode(Device device)
{
    device.ShowUI = false;
    device.DisableAfterAcquire = true;
            
    device.Open();
    device.PixelType = PixelType.BW;
    device.PixelFlavor = PixelFlavor.Chocolate;
    device.BitDepthReductionMode = BitDepthReductionMode.Threshold;
    device.Threshold = 128;
    device.UnitOfMeasure = UnitOfMeasure.Inches;
    device.Resolution = new Resolution(200f, 200f);
            
    device.Acquire();
}
Requirements

Target Platforms: Windows 8, Windows 7, Windows Vista, Windows XP, Windows Server 2012, Windows Server 2008, Windows Server 2003

See Also

Reference

Device Class
Device Members
GetSupportedThresholdValues Method
Open Method