AlphaBlendCommand Class

Summary

Combines image data from two images, using a specific opacity value.

Syntax

Objective-C

C++

Java

public class AlphaBlendCommand : RasterCommand

Public Class AlphaBlendCommand  
   Inherits RasterCommand

@interface LTAlphaBlendCommand : LTRasterCommand

public class AlphaBlendCommand extends RasterCommand

public ref class AlphaBlendCommand : public RasterCommand

Remarks

The opacity determines how much the affected image will show through the source image. For example, if the Opacity property (or the opacity parameter in the constructor) is set to 255 (completely opaque) then the source image will appear and the affected image will not show through the source image at all. If the opacity is 128 (half opacity), then the pixels for that area will consist of 50 percent from the source image and 50 percent from the affected image.
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 signed data images.
This command does not support 32-bit grayscale images.

For more information, refer to Introduction to Image Processing With LEADTOOLS.

Example

Run the AlphaBlendCommand on an image.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Effects; 
 
public void AlphaBlendCommandExample() 
{ 
   // Load an image 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.ThrowExceptionsOnInvalidImages = true; 
 
   RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Master.jpg")); 
 
   // Prepare the command 
   RasterImage SrcImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, @"ImageProcessingDemo\Image3.cmp"), 4, CodecsLoadByteOrder.Bgr, 1, 1); 
 
   AlphaBlendCommand command = new AlphaBlendCommand(); 
   //Combine SrcImage with image, with half opacity. 
   command.DestinationRectangle = new LeadRect(image.Width / 8, image.Height / 8, image.Width, image.Height); 
   command.SourceImage = SrcImage; 
   command.Opacity = 128; 
   command.Run(image); 
   codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "Result.jpg"), RasterImageFormat.Jpeg, 24); 
 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images"; 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing.Effects 
 
Public Sub AlphaBlendCommandExample() 
   Dim codecs As New RasterCodecs() 
   codecs.ThrowExceptionsOnInvalidImages = True 
 
   Dim leadImage As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Master.jpg")) 
 
   ' Prepare the command 
   Dim SrcImage As RasterImage 
   SrcImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "ImageProcessingDemo\image3.cmp"), 4, CodecsLoadByteOrder.Bgr, 1, 1) 
 
   Dim command As AlphaBlendCommand = New AlphaBlendCommand 
   'Combine SrcImage with image, with half opacity. 
   command.DestinationRectangle = New LeadRect(leadImage.Width \ 8, leadImage.Height \ 8, leadImage.Width, leadImage.Height) 
   command.SourceImage = SrcImage 
   command.Opacity = 128 
   command.Run(leadImage) 
   codecs.Save(leadImage, Path.Combine(LEAD_VARS.ImagesDir, "Result.jpg"), RasterImageFormat.Jpeg, 24) 
 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images" 
End Class

c#[Silverlight C# Example] 
using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Effects; 
using Leadtools.Examples; 
 
public void AlphaBlendCommandExample(RasterImage image, RasterImage srcImage, Stream outStream) 
{ 
   // Prepare the command 
   AlphaBlendCommand command = new AlphaBlendCommand(); 
   //Combine SrcImage with image, with half opacity. 
   command.DestinationRectangle = new LeadRect(image.Width / 8, image.Height / 8, image.Width, image.Height); 
   command.SourceImage = srcImage; 
   command.Opacity = 128; 
   command.Run(image); 
   // Save result image 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.Save(image, outStream, RasterImageFormat.Jpeg, 24); 
   image.Dispose(); 
   srcImage.Dispose(); 
} 
vb[Silverlight VB Example] 
Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing.Effects 
 
Public Sub AlphaBlendCommandExample(ByVal image As RasterImage, ByVal srcImage As RasterImage, ByVal outStream As Stream) 
   ' Prepare the command 
   Dim command As AlphaBlendCommand = New AlphaBlendCommand() 
   'Combine SrcImage with image, with half opacity. 
   command.DestinationRectangle = New LeadRect(image.Width / 8, image.Height / 8, image.Width, image.Height) 
   command.SourceImage = srcImage 
   command.Opacity = 128 
   command.Run(image) 
   ' Save result image 
   Dim codecs As RasterCodecs = New RasterCodecs() 
   codecs.Save(image, outStream, RasterImageFormat.Jpeg, 24) 
   image.Dispose() 
   srcImage.Dispose() 
End Sub