CorrelationCommand Class

Summary

This command compares the correlation image(or part of the correlation image) with all the areas of the same dimensions in the image to be searched (the Run method image) and finds those portions that match according to the measure of correlation. This command is available in the Document/Medical Toolkits.

Syntax

Objective-C

C++

Java

public class CorrelationCommand : RasterCommand

Public Class CorrelationCommand  
   Inherits RasterCommand

@interface LTCorrelationCommand : LTRasterCommand

public class CorrelationCommand extends RasterCommand

public ref class CorrelationCommand : public RasterCommand

Remarks

This command compares the correlation image (or part of the correlation image) with all the areas of the same dimensions in the image to be searched and finds those portions that match according to the measure of correlation. Correlation is a measure of association (resemblance) between two images. It varies from 0 (zero resemblance) to 100 (perfect resemblance). This command updates the Points property (or the points parameter of the Constructor) with the point of origin for those areas of the image to be searched where the resemblance with the correlation image (or part of the correlation image) is greater than the threshold. The correlation image dimensions must be less than or equal to the dimensions of the image to be searched.
For example:
1. Select an image of the object for which you want to look. Put it in the CorrelationImage property (or the correlationImage parameter of the constructor). For example:
2. Select an image that contains the image you wish to search and put it in the affected image. For example:
3. Call CorrelationCommand.
4. The command will update the Points array property (or the points parameter of the Constructor) with the point of origin (top-left) for each area of the image to be searched where the correlation with the correlation image is greater than the correlation threshold. The height and width of the rectangles are the same as for the correlation image.
5. The result is:
This command supports 12 and 16-bit grayscale and 48 and 64-bit color images. Support for 12-bit and 16-bit grayscale and 48-bit and 64-bit color images is available only in the Document/Medical toolkits.
This command does not support 32-bit grayscale images.
All images must be signed or unsigned.

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

Example

Run the CorrelationCommand on an image and applies the correlation filter.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Core; 
 
public void CorrelationCommandExample() 
{ 
   // Load an image 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.ThrowExceptionsOnInvalidImages = true; 
 
   RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "clean.tif")); 
 
   // Prepare the command 
   RasterImage DstImage = image.Clone(); 
   CorrelationCommand command = new CorrelationCommand(); 
   command.CorrelationImage = DstImage; 
   command.Threshold = 70; 
   command.XStep = 1; 
   command.YStep = 1; 
   command.Points = new LeadPoint[90]; 
   //Apply the correlation filter. 
   command.Run(image); 
 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS21\Resources\Images"; 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing.Core 
 
Public Sub CorrelationCommandExample() 
   Dim codecs As New RasterCodecs() 
   codecs.ThrowExceptionsOnInvalidImages = True 
 
   Dim leadImage As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "clean.tif")) 
 
   ' Prepare the command 
   Dim points() As LeadPoint 
   ReDim points(89) 
 
   Dim DstImage As RasterImage = leadImage.Clone() 
   Dim command As CorrelationCommand = New CorrelationCommand 
   command.CorrelationImage = DstImage 
   command.Threshold = 70 
   command.XStep = 1 
   command.YStep = 1 
   command.Points = points 
   'Apply the correlation filter. 
   command.Run(leadImage) 
 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\LEADTOOLS21\Resources\Images" 
End Class