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SetAlphaValuesCommand Class
See Also  Members   Example 
Leadtools.ImageProcessing Namespace : SetAlphaValuesCommand Class



Fills the image alpha values, while preserving the other image components.

Syntax

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

Example

This example will load an image, convert it to 32-bit/pixel and then set the alpha values to half the maximum allowed

Visual Basic Copy Code
Public Sub SetAlphaValuesCommandExample()
 RasterCodecs.Startup()
 Dim codecs As RasterCodecs = New RasterCodecs()

 Dim srcFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "Image1.cmp"
 Dim destFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "SetAlphaValuesCommand.bmp"

 ' Load the source image from disk
 Dim image As RasterImage = codecs.Load(srcFileName)

 ' Convert the image to 32-bits/pixel
 Dim colorResolution As ColorResolutionCommand = New ColorResolutionCommand(ColorResolutionCommandMode.InPlace, 32, RasterByteOrder.Bgr, RasterDitheringMethod.None, ColorResolutionCommandPaletteFlags.None, Nothing)
 colorResolution.Run(image)
 Debug.Assert(image.BitsPerPixel = 32)

 ' Set the alpha values
 Dim setAlphaValues As SetAlphaValuesCommand = New SetAlphaValuesCommand()
 setAlphaValues.Alpha = 128
 setAlphaValues.Run(image)

 ' Save the image back to disk
 codecs.Save(image, destFileName, RasterImageFormat.Bmp, 32)

 ' Clean Up
 image.Dispose()
 RasterCodecs.Shutdown()
      End Sub
C# Copy Code
public void SetAlphaValuesCommandExample() 
{ 
   RasterCodecs.Startup(); 
   RasterCodecs codecs = new RasterCodecs(); 
 
   string srcFileName = LeadtoolsExamples.Common.ImagesPath.Path + "Image1.cmp"; 
   string destFileName = LeadtoolsExamples.Common.ImagesPath.Path + "SetAlphaValuesCommand.bmp"; 
 
   // Load the source image from disk 
   RasterImage image = codecs.Load(srcFileName); 
 
   // Convert the image to 32-bits/pixel 
   ColorResolutionCommand colorResolution = new ColorResolutionCommand( 
      ColorResolutionCommandMode.InPlace, 
      32, 
      RasterByteOrder.Bgr, 
      RasterDitheringMethod.None, 
      ColorResolutionCommandPaletteFlags.None, 
      null); 
   colorResolution.Run(image); 
   Debug.Assert(image.BitsPerPixel == 32); 
 
   // Set the alpha values 
   SetAlphaValuesCommand setAlphaValues = new SetAlphaValuesCommand(); 
   setAlphaValues.Alpha = 128; 
   setAlphaValues.Run(image); 
 
   // Save the image back to disk 
   codecs.Save(image, destFileName, RasterImageFormat.Bmp, 32); 
 
   // Clean Up 
   image.Dispose(); 
   RasterCodecs.Shutdown(); 
}

Remarks

This command only works with images that are 32 or 64-bit bits per pixel.

Inheritance Hierarchy

System.Object
   Leadtools.ImageProcessing.RasterCommand
      Leadtools.ImageProcessing.SetAlphaValuesCommand

Requirements

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

See Also