MinimumToZeroCommand Class

Summary

Converts grayscale signed image to an unsigned one by shifting all the negative value of the image data, so the minimum negative value will be zero.

Syntax

Objective-C

C++

Java

public class MinimumToZeroCommand : RasterCommand

Public Class MinimumToZeroCommand  
   Inherits RasterCommand

@interface LTMinimumToZeroCommand : LTRasterCommand

public class MinimumToZeroCommand extends RasterCommand

public ref class MinimumToZeroCommand : public RasterCommand

Remarks

This command is similar to ConvertSignedToUnsignedCommand. This command automatically determines the value to be shift in order to convert the image to unsigned image. This command is used usually before the command ZeroToNegativeCommand. This command updates the Signed property of the RasterImage. This command also updates the MinValue and MaxValue properties of the RasterImage. This command does not support 8-bit images. 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 supports signed data images. This command does not support 32-bit grayscale images.

Example

This command will apply MultiscaleEnhancementCommand on a signed image, but since the MultiscaleEnhancementCommand does not support signed images, we will convert the image to an unsigned image, apply the effect, and then convert it back to a signed image.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Core; 
 
public void MinimumToZeroCommandExample() 
{ 
   // Load an image 
   RasterCodecs codecs = new RasterCodecs(); 
   codecs.ThrowExceptionsOnInvalidImages = true; 
 
   RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE2.dcm")); 
 
   // Prepare the command 
   // Convert the image to unsigned image by shifting the negative values to become positive. 
   MinimumToZeroCommand MinToZCommand = new MinimumToZeroCommand(); 
   MinToZCommand.Run(image); 
 
   // Apply multiscale enhancement 
   MultiscaleEnhancementCommand MultiScaleCommand = new MultiscaleEnhancementCommand(2000, 4, -1, 0, 0, MultiscaleEnhancementCommandType.Gaussian, MultiscaleEnhancementCommandFlags.EdgeEnhancement); 
 
   // Convert the image back to signed by shifting the same amount in the negative side. 
   ZeroToNegativeCommand command = new ZeroToNegativeCommand(); 
   command.MinimumInput = -32767; 
   command.MaximumInput = 32766; 
   command.MinimumOutput = 0; 
   command.MaximumOutput = 65535; 
   command.ShiftAmount = MinToZCommand.ShiftAmount; 
   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 MinimumToZeroCommandExample() 
   Dim codecs As New RasterCodecs() 
   codecs.ThrowExceptionsOnInvalidImages = True 
 
   Dim leadImage As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE2.dcm")) 
 
   ' Prepare the command 
   ' Convert the image to unsigned image by shifting the negative values to become positive. 
   Dim MinToZCommand As MinimumToZeroCommand = New MinimumToZeroCommand 
   MinToZCommand.Run(leadImage) 
 
   ' Apply multiscale enhancement 
   Dim MultiScaleCommand As MultiscaleEnhancementCommand = New MultiscaleEnhancementCommand(2000, 4, -1, 0, 0, MultiscaleEnhancementCommandType.Gaussian, MultiscaleEnhancementCommandFlags.EdgeEnhancement) 
 
   ' Convert the image back to signed by shifting the same amount in the negative side. 
   Dim command As ZeroToNegativeCommand = New ZeroToNegativeCommand 
   command.MinimumInput = -32767 
   command.MaximumInput = 32766 
   command.MinimumOutput = 0 
   command.MaximumOutput = 65535 
   command.ShiftAmount = MinToZCommand.ShiftAmount 
   command.Run(leadImage) 
 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\LEADTOOLS21\Resources\Images" 
End Class