Leadtools.ImageProcessing.Color Send comments on this topic. | Back to Introduction - All Topics | Help Version 16.5.9.25
ChangeContrastCommand Class
See Also  Members   Example 



Increases or decreases the contrast of the image.

Syntax

Visual Basic (Declaration) 
Public Class ChangeContrastCommand 
   Inherits RasterCommand
   Implements IRasterCommand 
Visual Basic (Usage)Copy Code
Dim instance As ChangeContrastCommand
C# 
public class ChangeContrastCommand : RasterCommand, IRasterCommand 
C++/CLI 
public ref class ChangeContrastCommand : public RasterCommand, IRasterCommand 

Example

Runs the ChangeContrastCommand on an image and increases its contrast.

Visual BasicCopy Code
Public Sub ChangeContrastCommandExample()
   RasterCodecs.Startup()
   Dim codecs As New RasterCodecs()
   codecs.ThrowExceptionsOnInvalidImages = True

   Dim leadImage As RasterImage = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Master.jpg")

   ' Prepare the command
   Dim command As ChangeContrastCommand = New ChangeContrastCommand
   'Increase the contrast by 25 percent of the possible range.
   command.Contrast = 250

   command.Run(leadImage)
   codecs.Save(leadImage, LeadtoolsExamples.Common.ImagesPath.Path + "Result.jpg", RasterImageFormat.Jpeg, 24)

   RasterCodecs.Shutdown()
End Sub
C#Copy Code
public void ChangeContrastCommandExample() 
{ 
   // Load an image 
   RasterCodecs.Startup(); 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.ThrowExceptionsOnInvalidImages = true; 
 
   RasterImage image = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Master.jpg"); 
 
   // Prepare the command 
   ChangeContrastCommand command = new ChangeContrastCommand(); 
   //Increase the contrast  by 25 percent  of the possible range. 
   command.Contrast = 250; 
   command.Run(image); 
   codecs.Save(image, LeadtoolsExamples.Common.ImagesPath.Path + "Result.jpg", RasterImageFormat.Jpeg, 24); 
 
   RasterCodecs.Shutdown(); 
}

Remarks

  • This command supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12 and 16-bit grayscale and 48 and 64-bit color images is available only in the Document/Medical toolkits.
  • This command does not support 32-bit grayscale images.

If the image has a LUT and you want to work on the image data, set RasterImage.UseLookupTable to false. Then, after calling the method, reset the UselookupTable property to true, as follows: 


rasterImage.UseLookupTable = false;
Method(rasterImage);

rasterImage.UseLookupTable = true;
For more information, refer to Changing Brightness and Contrast.

Inheritance Hierarchy

System.Object
   Leadtools.ImageProcessing.RasterCommand
      Leadtools.ImageProcessing.Color.ChangeContrastCommand

Requirements

Target Platforms: Microsoft .NET Framework 2.0, Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also