Public Shared Function CountLookupTableColorsExt( _
   ByVal lookupTable() As RasterColor16, _
   ByVal type As CountLookupTableColorsType _
) As CountLookupTableColorsResult

Visual Basic (Usage)	Copy Code
Dim lookupTable() As RasterColor16 Dim type As CountLookupTableColorsType Dim value As CountLookupTableColorsResult   value = CoreUtilities.CountLookupTableColorsExt(lookupTable, type)

public static CountLookupTableColorsResult CountLookupTableColorsExt( 
   RasterColor16[] lookupTable,
   CountLookupTableColorsType type
)

public:
static CountLookupTableColorsResult CountLookupTableColorsExt( 
   array<RasterColor16>^ lookupTable,
   CountLookupTableColorsType type
) 

Parameters

lookupTable

16-bit-bit lookup table array to be filled by this method.

type

Flag that indicates whether the LookupTable contains signed or unsigned data.

Run the CountLookupTableColorsExt method to get the number of entries and start index from the image.

Visual Basic

Copy Code

Public Sub CountLookupTableColorsExtExample()    RasterCodecs.Startup()    Dim codecs As New RasterCodecs()    codecs.ThrowExceptionsOnInvalidImages = True    Dim leadImage As RasterImage = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Image2.dcm")    ' Prepare the command    Dim command As CountLookupTableColorsResult = CoreUtilities.CountLookupTableColorsExt(leadImage.GetLookupTable16, CountLookupTableColorsType.Signed)    MessageBox.Show("First Index = " + command.FirstIndex.ToString + Chr(13) + "Number Of Entries = " + command.NumberOfEntries.ToString)    RasterCodecs.Shutdown() End Sub

C#

Copy Code

public void CountLookupTableColorsExtExample()  {     // Load an image     RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();     codecs.ThrowExceptionsOnInvalidImages = true;       RasterImage image = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Image2.dcm");       // Prepare the command     CountLookupTableColorsResult command = CoreUtilities.CountLookupTableColorsExt(image.GetLookupTable16(), CountLookupTableColorsType.Signed);     MessageBox.Show("First Index = " + command.FirstIndex + "\n" +        "Number Of Entries = " + command.NumberOfEntries);       RasterCodecs.Shutdown();  }

• Suppose you have a LookupTable with 4096 colors, the first 200 colors are black and the last 30 are white, the rest of the colors between black and white are gray. This is what the method will provide :
  
  NumberOfEntries (property of CountLookupTableColorsResult) : 3868.
  
  FirstIndex (property of CountLookupTableColorsResult) : 199.
• In more detail this is:
  
  Total number of entries: 4096 (0 - 4095).
  
  First index of the end color: 4095 - 30 + 1 (+1 to add the first index of the end color to the range).
  
  Number of occurrences of the starting color: 200 (0 - 199).
  
  The last index of the start color: 199.
  
  Total number of entries: (4095 - 30 + 1) - 199 + 1.
  
• This method supports 12 and 16-bit grayscale images. Support for 12 and 16-bit grayscale images is available only in the Document/Medical toolkits.
• This method uses 16-bit lookup tables. See CountLookupTableColors for a method that uses 8-bit lookup tables.

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

Reference