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ColorResolutionCommand Class
See Also  Members   Example 
Leadtools.ImageProcessing Namespace : ColorResolutionCommand Class



Converts an image from any bits-per-pixel to any bits-per-pixel.

Object Model


Syntax

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

Example

This example will run the ColorResolutionCommand on an image to convert it to 8 and 4 bits/pixel.

Visual Basic Copy Code
Public Sub ColorResolutionCommandExample()
 RasterCodecs.Startup()
 Dim codecs As RasterCodecs = New RasterCodecs()

 Dim srcFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "Image1.cmp"
 Dim destFileName1 As String = LeadtoolsExamples.Common.ImagesPath.Path + "Image1_colorres8.bmp"
 Dim destFileName2 As String = LeadtoolsExamples.Common.ImagesPath.Path + "Image1_colorres4.bmp"

 ' Load the source image from disk
 Dim image As RasterImage = codecs.Load(srcFileName)

 ' First color-res it to 8 bits per pixel using the Netscape palette into a seperate image
 Dim cmd As ColorResolutionCommand = New ColorResolutionCommand()
 cmd.Mode = ColorResolutionCommandMode.CreateDestinationImage
 cmd.BitsPerPixel = 8
 cmd.Order = RasterByteOrder.Rgb
 cmd.DitheringMethod = RasterDitheringMethod.None
 cmd.PaletteFlags = ColorResolutionCommandPaletteFlags.UsePalette
 cmd.SetPalette(RasterPalette.Netscape())
 cmd.Run(image)

 Dim destImage As RasterImage = cmd.DestinationImage
 Debug.Assert(destImage.BitsPerPixel = 8)

 ' Save it to disk
 codecs.Save(destImage, destFileName1, RasterImageFormat.Bmp, 8)
 destImage.Dispose()

 ' Now color-res the image in-place to 4-bits per pixel using the Optimized palette
 cmd.Mode = ColorResolutionCommandMode.InPlace
 cmd.BitsPerPixel = 4
 cmd.Order = RasterByteOrder.Rgb
 cmd.DitheringMethod = RasterDitheringMethod.None
 cmd.PaletteFlags = ColorResolutionCommandPaletteFlags.Optimized
 cmd.Run(image)
 Debug.Assert(image.BitsPerPixel = 4)

 ' Save it to disk
 codecs.Save(image, destFileName2, RasterImageFormat.Bmp, 4)
 destImage.Dispose()

 ' Clean Up
 image.Dispose()
 RasterCodecs.Shutdown()
      End Sub
C# Copy Code
public void ColorResolutionCommandExample() 
{ 
   RasterCodecs.Startup(); 
   RasterCodecs codecs = new RasterCodecs(); 
 
   string srcFileName = LeadtoolsExamples.Common.ImagesPath.Path + "Image1.cmp"; 
   string destFileName1 = LeadtoolsExamples.Common.ImagesPath.Path + "Image1_colorres8.bmp"; 
   string destFileName2 = LeadtoolsExamples.Common.ImagesPath.Path + "Image1_colorres4.bmp"; 
 
   // Load the source image from disk 
   RasterImage image = codecs.Load(srcFileName); 
 
   // First color-res it to 8 bits per pixel  using the Netscape palette into a seperate image 
   ColorResolutionCommand cmd = new ColorResolutionCommand(); 
   cmd.Mode = ColorResolutionCommandMode.CreateDestinationImage; 
   cmd.BitsPerPixel = 8; 
   cmd.Order = RasterByteOrder.Rgb; 
   cmd.DitheringMethod = RasterDitheringMethod.None; 
   cmd.PaletteFlags = ColorResolutionCommandPaletteFlags.UsePalette; 
   cmd.SetPalette(RasterPalette.Netscape()); 
   cmd.Run(image); 
 
   RasterImage destImage = cmd.DestinationImage; 
   Debug.Assert(destImage.BitsPerPixel == 8); 
 
   // Save it to disk 
   codecs.Save(destImage, destFileName1, RasterImageFormat.Bmp, 8); 
   destImage.Dispose(); 
 
   // Now color-res the image in-place to 4-bits per pixel using the Optimized palette 
   cmd.Mode = ColorResolutionCommandMode.InPlace; 
   cmd.BitsPerPixel = 4; 
   cmd.Order = RasterByteOrder.Rgb; 
   cmd.DitheringMethod = RasterDitheringMethod.None; 
   cmd.PaletteFlags = ColorResolutionCommandPaletteFlags.Optimized; 
   cmd.Run(image); 
   Debug.Assert(image.BitsPerPixel == 4); 
 
   // Save it to disk 
   codecs.Save(image, destFileName2, RasterImageFormat.Bmp, 4); 
   destImage.Dispose(); 
 
   // Clean Up 
   image.Dispose(); 
   RasterCodecs.Shutdown(); 
}

Remarks

This class provides flexibility in specifying the output destination and in specifying the palette to use.

For general information about dithering, refer to Color Resolution and Dithering and Dithering Methods.

You can convert the image in place or create a new converted image.

In specifying a palette, you can use simple palette options, or you can specify a palette that is tailored to your needs. The tailored palette can be any size that you specify. It can include specific colors, reserved blank entries, and open entries that this method fills with optimized colors.

If you use the same tailored palette more than once, you can improve performance by creating a table, using RasterUserMatchTable.

NOTE: Using this class to change the color order of a 24-bit or 32-bit image (i.e. RGB to BGR) will have no effect on the image when painting or saving (to a file). If you want to change the visual appearance, you can simply swap the color order using the RasterImage.Order property.

When converting to 32 and 64-bit images, you can control whether to initialize the alpha channel values to all 0's or 1's through the InitAlpha property.

This class does not support signed data images. An exception will be thrown if a signed data image is passed to this class.

For more information, refer to Introduction to Image Processing With LEADTOOLS.

For more information, refer to Introduction - Palette Handling.

Inheritance Hierarchy

System.Object
   Leadtools.ImageProcessing.RasterCommand
      Leadtools.ImageProcessing.ColorResolutionCommand

Requirements

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

See Also