FromEmf(IntPtr,Int32,Int32) Method

Visual Basic
C#
WinRT C#
WinRT JavaScript
C++

public static RasterImage FromEmf( 
   IntPtr hemf,
   int width,
   int height
)

'Declaration
 
Public Overloads Shared Function FromEmf( _
   ByVal hemf As IntPtr, _
   ByVal width As Integer, _
   ByVal height As Integer _
) As RasterImage

'Usage
 
Dim hemf As IntPtr
Dim width As Integer
Dim height As Integer
Dim value As RasterImage
 
value = RasterImageConverter.FromEmf(hemf, width, height)

public static RasterImage FromEmf( 
   IntPtr hemf,
   int width,
   int height
)

 function Leadtools.Drawing.RasterImageConverter.FromEmf(IntPtr,Int32,Int32)( 
   hemf ,
   width ,
   height 
)

public:
static RasterImage^ FromEmf( 
   IntPtr hemf,
   int width,
   int height
)

Parameters

hemf: Handle to the EMF to be converted.
width: Amount by which to scale the enhanced metafiles original width.
height: Amount by which to scale the enhanced metafiles original height.

Return Value

The newly created Leadtools.RasterImage object.

Some metafiles do not have a background color, and hence, when the metafile is used to create a Leadtools.RasterImage object, the area not covered by the metafile objects will contain the default image background color (black). To create a raster image from a metafile like this with a specific background color, use FromEmf(hemf, width, height, backColor).

When this method is completed, there are two copies of the drawing in memory: the new Leadtools.RasterImage object and the original EMF. Freeing one will not affect the other.

The enhanced metafile can be loaded at the original dimension or scaled by using the width and height parameters.

If width == 0 and height == 0 - the enhanced metafile is loaded at the size present in the file.

If width == 0 and height > 0 - the enhanced metafile is stretched so that it has the height height (preserving the aspect ratio).

If width > 0 and height == 0 - the enhanced metafile is stretched so that it has the width width (preserving the aspect ratio).

If width > 0 and height > 0 - the enhanced metafile is stretched so that it has the width width and height height (the aspect ratio is ignored).

This method does not support signed images.

For more information refer to RasterImage and GDI/GDI+.

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

<DllImport("Gdi32", CharSet:=CharSet.Auto)> _
   Private Shared Function DeleteEnhMetaFile(ByVal hemf As IntPtr) As Integer
   End Function

   Public Sub FromEmfExample()
      Dim codecs As New RasterCodecs()

      Dim hemf As IntPtr

      ' Load an image
      Using image As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"), 24, CodecsLoadByteOrder.BgrOrGray, 1, 1)
         ' Convert it to EMF
         hemf = RasterImageConverter.ToEmf(image)

         ' Note, since we converted to an EMF we have two copies of the image in memory and "image" is still usable
      End Using

      ' Convert the EMF back to a RasterImage preserving the size
      Using image As RasterImage = RasterImageConverter.FromEmf(hemf, 0, 0)
         ' Not since we converted from the EMF, we need to delete it ourselves
         DeleteEnhMetaFile(hemf)

         ' Save it to disk
         codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "Image1_FromEmf.bmp"), RasterImageFormat.Bmp, 24)
      End Using

      ' Clean up
      codecs.Dispose()
   End Sub

Public NotInheritable Class LEAD_VARS
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class

[DllImport("Gdi32", CharSet = CharSet.Auto)]
   private static extern int DeleteEnhMetaFile(IntPtr hemf);

   public void FromEmfExample()
   {
      RasterCodecs codecs = new RasterCodecs();

      IntPtr hemf;

      // Load an image
      using(RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"), 24, CodecsLoadByteOrder.BgrOrGray, 1, 1))
      {
         // Convert it to EMF
         hemf = RasterImageConverter.ToEmf(image);

         // Note, since we converted to an EMF we have two copies of the image in memory and "image" is still usable
      }

      // Convert the EMF back to a RasterImage preserving the size
      using(RasterImage image = RasterImageConverter.FromEmf(hemf, 0, 0))
      {
         // Not since we converted from the EMF, we need to delete it ourselves
         DeleteEnhMetaFile(hemf);

         // Save it to disk
         codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "Image1_FromEmf.bmp"), RasterImageFormat.Bmp, 24);
      }

      // Clean up
      codecs.Dispose();
   }

static class LEAD_VARS
{
   public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

RasterImageConverter Class
RasterImageConverter Members
Overload List
FromEmf(hemf, width, height, backColor)
ChangeFromEmf(IntPtr,Int32,Int32) Method
ChangeFromWmf(IntPtr,Int32,Int32) Method
FromWmf
ChangeToEmf Method
ChangeToWmf Method
ToEmf
ToWmf