ApplyLinearVoiLookupTableCommand Class

This command is available in the Document and Medical Imaging toolkits.

• This class sets up the window-leveling options for paint or paint and image processing methods for a specific image through a linear transformation described by the window center and width. In the DICOM world, this remapping of the Lookup Table is referred to as "applying a linear VOI LookupTable (LookupTable)".
• The DICOM standard states:
• "Window Center and Window Width specify a linear conversion from stored pixel values (after any Modality LookupTable or Rescale Slope and Intercept specified in the IOD have been applied) to values to be displayed. Window Center contains the input value that is the center of the window. Window Width contains the width of the window." Refer to "VOI LookupTable (LookupTable) Module Attributes" in the DICOM standard for more details.
• This class does not change the image data; it only updates the entries inside the image LookupTable.
• It is best to always set the VoiLookupTableCommandFlags.UpdateMinMax flag.
• In the DICOM world you must set the VoiLookupTableCommandFlags.ReverseOrder flag if the photometric interpretation of the image is "MONOCHROME1", where the minimum grayscale value is intended to be displayed as white after any VOI gray scale transformations have been performed.
• This class supports 12 and 16-bit grayscale. Support for 12 and 16-bit grayscale is available only in the Document/Medical toolkits.
• This command does not support 32-bit grayscale images.

In Silverlight versions of LEADTOOLS, this image processing command will fail if the image data for the RasterImage object is stored internally using a Silverlight WriteableBitmap object. For more information, refer to Image Processing Command Limitations in Silverlight.

Run the ApplyLinearVoiLookupTableCommand on an image.

• C#
• Visual Basic
• WinRT C#
• WinRT JavaScript
• Silverlight C#
• Silverlight VB

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Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.ImageProcessing.Core

   
Public Sub ApplyLinearVoiLookupTableCommandExample()
   Dim codecs As New RasterCodecs()
   codecs.ThrowExceptionsOnInvalidImages = True
   Dim leadImage As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE2.dcm"))

   ' Prepare the command
   Dim command As ApplyLinearVoiLookupTableCommand = New ApplyLinearVoiLookupTableCommand
   command.Flags = VoiLookupTableCommandFlags.None
   command.Center = 330.0
   command.Width = 600.0
   ' Apply "Abdomen T1" window-level , high bit is assumed 
   ' to be "11" and low bit "0. 
   command.Run(leadImage)

End Sub

Public NotInheritable Class LEAD_VARS
Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class

using Leadtools;
using Leadtools.Codecs;
using Leadtools.ImageProcessing.Core;

      
public void ApplyLinearVoiLookupTableCommandExample()
{
   // Load an image
   RasterCodecs codecs = new RasterCodecs();
   codecs.ThrowExceptionsOnInvalidImages = true;
   RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE2.dcm"));

   // Prepare the command
   ApplyLinearVoiLookupTableCommand command = new ApplyLinearVoiLookupTableCommand();
   command.Flags  = VoiLookupTableCommandFlags.None;
   command.Center = 330.0;
   command.Width  = 600.0;
   // Apply "Abdomen T1" window-level , high bit is assumed 
   // to be "11" and low bit "0. 
   command.Run(image);

}

static class LEAD_VARS
{
public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}

function ApplyLinearVoiLookupTableCommandExample()
{
   var codecs = new Leadtools.Codecs.RasterCodecs();
   codecs.throwExceptionsOnInvalidImages = true;

   // Load the image
   var srcFileName = "Assets\\Image2.dcm";
   return Tools.AppInstallFolder().getFileAsync(srcFileName).then(function (loadFile) {
      return codecs.loadAsync(Leadtools.LeadStreamFactory.create(loadFile));
   }).then(function (image){
      // Prepare the command
      with (Leadtools.ImageProcessing.Core) {
         // Prepare the command
         var command = new ApplyLinearVoiLookupTableCommand();
         command.flags  = VoiLookupTableCommandFlags.none;
         command.center = 330.0;
         command.width  = 600.0;
         // Apply "Abdomen T1" window-level , high bit is assumed 
         // to be "11" and low bit "0. 
         command.run(image);
      }
   });
}

using Leadtools;
using Leadtools.Codecs;
using Leadtools.ImageProcessing.Core;

      
public async Task ApplyLinearVoiLookupTableCommandExample()
{
   // Load an image
   RasterCodecs codecs = new RasterCodecs();
   codecs.ThrowExceptionsOnInvalidImages = true;
   // Load the image
   string srcFileName = @"Assets\IMAGE2.dcm";
   StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName);
   RasterImage image = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile));

   // Prepare the command
   ApplyLinearVoiLookupTableCommand command = new ApplyLinearVoiLookupTableCommand();
   command.Flags  = VoiLookupTableCommandFlags.None;
   command.Center = 330.0;
   command.Width  = 600.0;
   // Apply "Abdomen T1" window-level , high bit is assumed 
   // to be "11" and low bit "0. 
   command.Run(image);

}

using Leadtools;
using Leadtools.Examples;
using Leadtools.Codecs;
using Leadtools.ImageProcessing.Core;

public void ApplyLinearVoiLookupTableCommandExample(RasterImage image, Stream outStream)
{
   // Prepare the command
   ApplyLinearVoiLookupTableCommand command = new ApplyLinearVoiLookupTableCommand();
   command.Flags = VoiLookupTableCommandFlags.None;
   command.Center = 330.0;
   command.Width = 600.0;
   // Apply "Abdomen T1" window-level , high bit is assumed 
   // to be "11" and low bit "0. 
   command.Run(image);
   // Save result image
   RasterCodecs codecs = new RasterCodecs();
   codecs.Save(image, outStream, RasterImageFormat.Jpeg, 24);
   image.Dispose();
}

Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.ImageProcessing.Core

Public Sub ApplyLinearVoiLookupTableCommandExample(ByVal image As RasterImage, ByVal outStream As Stream)
   ' Prepare the command
   Dim command As ApplyLinearVoiLookupTableCommand = New ApplyLinearVoiLookupTableCommand()
   command.Flags = VoiLookupTableCommandFlags.None
   command.Center = 330.0
   command.Width = 600.0
   ' Apply "Abdomen T1" window-level , high bit is assumed 
   ' to be "11" and low bit "0. 
   command.Run(image)
   ' Save result image
   Dim codecs As RasterCodecs = New RasterCodecs()
   codecs.Save(image, outStream, RasterImageFormat.Jpeg, 24)
   image.Dispose()
End Sub

Target Platforms

Reference

ApplyLinearVoiLookupTableCommand Members
Leadtools.ImageProcessing.Core Namespace
Changing Brightness and Contrast
ApplyVoiLookupTableCommand Class
Leadtools.ImageProcessing.Color.RemapIntensityCommand
ApplyModalityLookupTableCommand Class
ApplyLinearModalityLookupTableCommand Class
Leadtools.ImageProcessing.Color.AdjustTintCommand
Leadtools.ImageProcessing.Color.GammaCorrectExtendedCommand