ToDib Method

Summary

Gets an unmanaged pointer containing a Windows device independent bitmap (DIB) version of this image.

Syntax

Objective-C

C++

public IntPtr ToDib( 
   RasterConvertToDibType type 
)

Public Function ToDib( _ 
   ByVal type As RasterConvertToDibType _ 
) As IntPtr

- (nullable LTHandle *)toDib:(LTRasterConvertToDibType)type

public: 
IntPtr ToDib(  
   RasterConvertToDibType type 
)

Parameters

type
Type of DIB to create.

Return Value

A handle to the Windows DIB.

Remarks

When this method is completed, there are two copies of the image in memory: the DIB and the original RasterImage. Freeing one will not affect the other.

This methods allocates a DIB bitmap and copies the RasterImage to the DIB.

NOTE: This method returns the data in an unmanaged buffer. The caller is responsible for freeing the DIB's IntPtr when it is no longer needed. You can use Marshal.FreeHGlobal.

A DIB consists of one of the following:

a BITMAPFILEHEADER
a BITMAPV4HEADER(introduced in Windows 95 and Windows NT 4.0)
or a BITMAPV5HEADER (introduced in Windows 2000 and Windows 98)

followed by a color table and then the bitmap data. The resulting DIB type is determined by the value of the type parameter.

The orientation of the image and color order will depend on how the image was loaded into the RasterImage.

When you no longer need the DIB, you can free it using the Windows GlobalFree function or FreeHGlobal.

For more information on DDBs and DIBs, refer to Introduction: DIBs, DDBs, and the Clipboard.

This function does not support signed images.

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Core; 
using Leadtools.ImageProcessing.Color; 
using Leadtools.Dicom; 
using Leadtools.Drawing; 
using Leadtools.Controls; 
using LeadtoolsExamples.Common; 
using Leadtools.Svg; 
 
public void ToDibExample() 
{ 
   RasterCodecs codecs = new RasterCodecs(); 
 
   IntPtr dib; 
 
   using (RasterImage image = codecs.Load(Path.Combine(ImagesPath.Path, "Image1.cmp"))) 
   { 
      dib = image.ToDib(RasterConvertToDibType.BitmapInfoHeader); 
   } 
 
   using (RasterImage image = RasterImage.FromDib(dib)) 
   { 
      codecs.Save(image, Path.Combine(ImagesPath.Path, "Image1_FromDib.bmp"), RasterImageFormat.Bmp, 0); 
   } 
 
   Marshal.FreeHGlobal(dib); 
 
   codecs.Dispose(); 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing 
Imports Leadtools.ImageProcessing.Core 
Imports Leadtools.ImageProcessing.Color 
Imports Leadtools.Controls 
Imports Leadtools.Dicom 
Imports Leadtools.Drawing 
Imports Leadtools.Svg 
 
Public Sub ToDibExample() 
   Dim codecs As RasterCodecs = New RasterCodecs() 
 
   Dim dib As IntPtr 
   Using image As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp")) 
      dib = image.ToDib(RasterConvertToDibType.BitmapInfoHeader) 
   End Using 
 
   Using image As RasterImage = RasterImage.FromDib(dib) 
      codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "Image1_FromDib.bmp"), RasterImageFormat.Bmp, 0) 
   End Using 
 
   Marshal.FreeHGlobal(dib) 
 
   codecs.Dispose() 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images" 
End Class