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'Declaration
Public Overloads Shared Function FromWmf( _ ByVal hwmf As IntPtr, _ ByVal width As Integer, _ ByVal height As Integer _ ) As RasterImage
'Usage
Dim hwmf As IntPtr Dim width As Integer Dim height As Integer Dim value As RasterImage value = RasterImageConverter.FromWmf(hwmf, width, height)
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 FromWmf(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 WMF. Freeing one will not affect the other.
The metafile can be loaded at the original dimension or scaled by using the width and height parameters.
If width == 0 and height == 0 - the metafile is loaded at the size present in the file.
If width == 0 and height > 0 - the metafile is stretched so that it has the height height (preserving the aspect ratio).
If width > 0 and height == 0 - the metafile is stretched so that it has the width width (preserving the aspect ratio).
If width > 0 and height > 0 - the 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+.
This example loads a Leadtools.RasterImage, converts it to a WMF, then converts the WMF back to a Leadtools.RasterImage.
Imports Leadtools Imports Leadtools.Codecs Imports Leadtools.Drawing Imports Leadtools.ImageProcessing Imports Leadtools.ImageProcessing.Color <DllImport("Gdi32", CharSet:=CharSet.Auto)> _ Private Shared Function DeleteMetaFile(ByVal hwmf As IntPtr) As Integer End Function <TestMethod()> _ Public Sub FromWmfExample() Dim codecs As New RasterCodecs() Dim hwmf 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 WMF hwmf = RasterImageConverter.ToWmf(image) ' Note, since we converted to an WMF we have two copies of the image in memory and "image" is still usable End Using ' Convert the WMF back to a RasterImage preserving the size Using image As RasterImage = RasterImageConverter.FromWmf(hwmf, 0, 0) ' Not since we converted from the WMF, we need to delete it ourselves DeleteMetaFile(hwmf) ' Save it to disk codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "Image1_FromWmf.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
using Leadtools; using Leadtools.Codecs; using Leadtools.Drawing; using Leadtools.ImageProcessing; using Leadtools.ImageProcessing.Color; [DllImport("Gdi32", CharSet = CharSet.Auto)] private static extern int DeleteMetaFile(IntPtr hwmf); [TestMethod] public void FromWmfExample() { RasterCodecs codecs = new RasterCodecs(); IntPtr hwmf; // Load an image using(RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"), 24, CodecsLoadByteOrder.BgrOrGray, 1, 1)) { // Convert it to WMF hwmf = RasterImageConverter.ToWmf(image); // Note, since we converted to an WMF we have two copies of the image in memory and "image" is still usable } // Convert the WMF back to a RasterImage preserving the size using(RasterImage image = RasterImageConverter.FromWmf(hwmf, 0, 0)) { // Not since we converted from the WMF, we need to delete it ourselves DeleteMetaFile(hwmf); // Save it to disk codecs.Save(image, Path.Combine(LEAD_VARS.ImagesDir, "Image1_FromWmf.bmp"), RasterImageFormat.Bmp, 24); } // Clean up codecs.Dispose(); } static class LEAD_VARS { public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images"; }