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CorrelationListCommand Class
See Also  Members   Example 
Leadtools.ImageProcessing.Core Namespace : CorrelationListCommand Class



Compares the images in a list with all the areas of the same dimensions in an image and finds those portions that match according to the measure of correlation. This method is only available in the Document/Medical toolkits.

Syntax

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

Example

Run the CorrelationListCommand on an image.

Visual BasicCopy Code
Public Sub CorrelationListCommandExample()
   ' Load an image
   RasterCodecs.Startup()
   Dim codecs As RasterCodecs = New RasterCodecs()
   codecs.ThrowExceptionsOnInvalidImages = True

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

   Dim command As CorrelationListCommand = New CorrelationListCommand()
   Dim copyRectangle As CopyRectangleCommand = New CopyRectangleCommand()

   Dim rc_cor As Rectangle = New Rectangle(327, 378, 22, 28)
   copyRectangle.Rectangle = rc_cor
   copyRectangle.Run(image)
   command.CorrelationImage = copyRectangle.DestinationImage.Clone()

   rc_cor = New Rectangle(283, 378, 22, 28)
   copyRectangle.Rectangle = rc_cor
   copyRectangle.Run(image)
   command.CorrelationImage.AddPage(copyRectangle.DestinationImage.Clone())

   Dim points(30) As Point
   Dim listIndex(30) As Integer

   command.Points = points
   command.ListIndex = listIndex
   command.Threshold = 90
   command.XStep = 1
   command.YStep = 1
   command.Run(image)

   RasterCodecs.Shutdown()
End Sub
C#Copy Code
public void CorrelationListCommandExample() 
{ 
   // Load an image 
   RasterCodecs.Startup(); 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.ThrowExceptionsOnInvalidImages = true; 
 
   RasterImage image = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Master.jpg"); 
 
   CorrelationListCommand command = new CorrelationListCommand(); 
   CopyRectangleCommand copyRectangle = new CopyRectangleCommand(); 
 
   Rectangle rc_cor = new Rectangle(327, 378, 22, 28); 
   copyRectangle.Rectangle = rc_cor; 
   copyRectangle.Run(image); 
   command.CorrelationImage = copyRectangle.DestinationImage.Clone(); 
 
   rc_cor = new Rectangle(283, 378, 22, 28); 
   copyRectangle.Rectangle = rc_cor; 
   copyRectangle.Run(image); 
   command.CorrelationImage.AddPage(copyRectangle.DestinationImage.Clone()); 
 
   command.Points = new Point[30]; 
   command.ListIndex = new int[30]; 
   command.Threshold = 90; 
   command.XStep = 1; 
   command.YStep = 1; 
   command.Run(image); 
 
   RasterCodecs.Shutdown(); 
}

Remarks

  • This method compares the images in a list with all the areas of the same dimensions in image and finds those areas that match according to the measure of correlation.
  • All the list images must have the same dimensions. The dimensions must be less than or equal to the image dimensions.
  • Correlation is a measure of association (resemblance) between two images. It varies from 0 (zero resemblance) to 100 (perfect resemblance).
  • This method updates the Points parameter with the point of origin for those areas of the image where the resemblance with an image in the list is greater than the value of Threshold. It also updates ListIndex with the index of that image.
  • For example:
    1. Select images of the objects for which you want to look and put them in a list
      For example:

    2. Select an image that contains the objects for which you are searching.
      For example:
    3. Set XStep = 1, YStep = 1 and Threshold = 90 then run the command
    4. Points array will be updated with the point of origin (top-left) for each area of the image where the correlation with an image in the list is greater than the correlation Threshold. The height and width of the rectangles are the same as for list images.
    5. The result
  • This method 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.
  • If the image has a region, this method works only on the region. If the image does not have a region, this method works on the entire image.
  • This method does not support signed data images.
  • This command does not support 32-bit grayscale images.

Inheritance Hierarchy

System.Object
   Leadtools.ImageProcessing.RasterCommand
      Leadtools.ImageProcessing.Core.CorrelationListCommand

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