Leadtools.ImageProcessing.Color Send comments on this topic. | Back to Introduction - All Topics | Help Version 15.12.10
LightControlCommand Class
See Also  Members   Example 




Lightens or darkens all or part of an image by remapping the pixel values.

Syntax

Visual Basic (Declaration) 
Public Class LightControlCommand 
   Inherits RasterCommand
   Implements IRasterCommand 
Visual Basic (Usage)Copy Code
Dim instance As LightControlCommand
C# 
public class LightControlCommand : RasterCommand, IRasterCommand 
Managed Extensions for C++ 
public __gc class LightControlCommand : public RasterCommand, IRasterCommand 
C++/CLI 
public ref class LightControlCommand : public RasterCommand, IRasterCommand 

Example

Visual BasicCopy Code
ImageProcessing.Color.LightControlCommand
   Public Sub LightControlCommandExample()
      RasterCodecs.Startup()
      Dim codecs As New RasterCodecs()
      codecs.ThrowExceptionsOnInvalidImages = True

      Dim leadImage As RasterImage = codecs.Load("C:\Program Files\LEAD Technologies\LEADTOOLS 15\Images\Master.jpg")

      ' Prepare the command
      Dim LowerAverage() As Integer
      ReDim LowerAverage(2)
      Dim Average() As Integer
      ReDim Average(2)
      Dim UpperAverage() As Integer
      ReDim UpperAverage(2)
      LowerAverage(0) = 100 'for blue, gray or yuv
      LowerAverage(1) = 120 'for green
      LowerAverage(2) = 80 'for red
      Average(0) = 150 'for blue, gray or yuv
      Average(1) = 140 'for green
      Average(2) = 128 'for red
      UpperAverage(0) = 190 'for blue, gray or yuv
      UpperAverage(1) = 200 'for green
      UpperAverage(2) = 220 'for red
      Dim command As LightControlCommand = New LightControlCommand(LowerAverage, Average, UpperAverage, LightControlCommandType.Yuv)
      ' change the lightness of the image.
      command.Run(leadImage)
      codecs.Save(leadImage, "C:\Program Files\LEAD Technologies\LEADTOOLS 15\Images\Result.jpg", RasterImageFormat.Jpeg, 24)

      RasterCodecs.Shutdown()
   End Sub
C#Copy Code
ImageProcessing.Color.LightControlCommand 
      public void LightControlCommandExample() 
      { 
         // Load an image 
         RasterCodecs.Startup(); 
         RasterCodecs codecs = new RasterCodecs(); 
         codecs.ThrowExceptionsOnInvalidImages = true; 
 
         RasterImage image = codecs.Load(@"C:\Program Files\LEAD Technologies\LEADTOOLS 15\Images\Master.jpg"); 
 
         // Prepare the command 
         int[] LowerAverage = new int[3]; 
         int[] Average  = new int[3]; 
         int[] UpperAverage = new int[3]; 
         LowerAverage[0] = 100;  //for blue, gray or yuv 
         LowerAverage[1] = 120;  //for green 
         LowerAverage[2] = 80;   //for red 
         Average[0] = 150;       //for blue, gray or yuv 
         Average[1] = 140;       //for green 
         Average[2] = 128;       //for red 
         UpperAverage[0] = 190;  //for blue, gray or yuv 
         UpperAverage[1] = 200;  //for green 
         UpperAverage[2] = 220;  //for red  
         LightControlCommand command = new LightControlCommand(LowerAverage, Average, UpperAverage, LightControlCommandType.Yuv); 
         // change the lightness of the image. 
         command.Run(image); 
         codecs.Save(image, @"C:\Program Files\LEAD Technologies\LEADTOOLS 15\Images\Result.jpg", RasterImageFormat.Jpeg, 24); 
 
         RasterCodecs.Shutdown(); 
      }

Remarks

  • This class remaps the pixel values of the image across the full range of available pixel values, in order to achieve the values passed in LowerAverage, Average and UpperAverage. For example, call this method for a grayscale image, with Average containing 150, LowerAverage containing 100 and UpperAverage containing 190. The pixels of the image will be remapped so that the new average pixel value for the entire image will be 150, the new average value for those pixels with a value between 0 and the average value for the entire image will be 100, and the new average value for those pixels with a value between the average value for the entire image and the maximum pixel value in the image will be 190.
  • This class 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 class does not support signed data images.
  • For an example, see the following figure:

  • The following figure shows the same image, after the effect has been applied:

  • To obtain this effect, the following settings were used with the method: LowerAverage = 100
    Average = 255
    UpperAverage = 255
    Type = LightControlCommandType.Yuv
  • This command does not support 32-bit grayscale images.
For more information, refer to Changing Brightness and Contrast.
For more information, refer to Correcting Colors.

Inheritance Hierarchy

System.Object
   Leadtools.ImageProcessing.RasterCommand
      Leadtools.ImageProcessing.Color.LightControlCommand

Requirements

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

See Also