DicomModalityLutAttributes Class

Summary

The DicomModalityLutAttributes is used by the methods GetModalityLutAttributes and SetModalityLut to get and set the attributes that describe the Modality LUT.

Syntax

Objective-C

C++/CLI

Java

public class DicomModalityLutAttributes

@interface LTDicomModalityLutAttributes : NSObject

public class DicomModalityLutAttributes

public ref class DicomModalityLutAttributes

Remarks

The properties of this class are based on the attributes of the "Modality LUT Module". Please see "Modality LUT Module Attributes" in the DICOM standard for more details.
The DICOM standard states that: "Either a Modality LUT Sequence containing a single Item or Rescale Slope and Intercept values shall be present, but not both." For this reason, both IsModalityLutSequence and IsRescaleSlopeIntercept cannot be set to true at the same time.
When using this class with the SetModalityLut method you must set one of the flags, either IsModalityLutSequence or IsRescaleSlopeIntercept. If you set IsModalityLutSequence, you must populate IsModalityLutSequence, LutExplanation and LutType with valid values. If you set IsRescaleSlopeIntercept, you must populate RescaleIntercept, RescaleType with valid values.
According to the DICOM standard when the number of table entries under the "LUT Data" (0028,3006) element is equal to 2^16 then the value of FirstStoredPixelValueMapped, NumberOfEntries and EntryBits. NumberOfEntries shall be 0. However, the 2 methods, GetModalityLutAttributes and SetModalityLut, do NOT have this limitation. When you call GetModalityLutAttributes, it will automatically set value in the dataset to 0 if NumberOfEntries is equal to 2^16. The same applies to SetModalityLut.

Example

using Leadtools; 
using Leadtools.Dicom; 
 
 
public void TestSetModalityLut() 
{ 
   string dicomFileName = Path.Combine(LEAD_VARS.ImagesDir, "DICOM", "image3.dcm"); 
   //Make sure to initialize the DICOM engine, this needs to be done only once  
   //In the whole application 
   DicomEngine.Startup(); 
   using (DicomDataSet ds = new DicomDataSet()) 
   { 
      //Load DICOM File 
      ds.Load(dicomFileName, DicomDataSetLoadFlags.None); 
      DicomModalityLutAttributes modalityLutAttributes = new DicomModalityLutAttributes(); 
      //No Modality LUT Sequence (0028,3000)  
      modalityLutAttributes.IsModalityLutSequence = false; 
      //Yes there is a rescale slope and intercept 
      modalityLutAttributes.IsRescaleSlopeIntercept = true; 
      modalityLutAttributes.RescaleIntercept = -128.0; 
      modalityLutAttributes.RescaleSlope = 1.0; 
      modalityLutAttributes.RescaleType = "UNSPECIFIED"; 
      // Delete the existing modality LUT,  
      // although we don't have to !  
      ds.DeleteModalityLut(); 
      //Set rescale slope and intercept 
      ds.SetModalityLut(modalityLutAttributes, null); 
      ds.Save(Path.Combine(LEAD_VARS.ImagesDir, "DICOM", "MLUT.dcm"), DicomDataSetSaveFlags.None); 
   } 
   DicomEngine.Shutdown(); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images"; 
}