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GetOverlayImage Method
See Also 
Leadtools Namespace > RasterImage Class : GetOverlayImage Method



index
The index of the overlay being retrieved. This index is zero-based and should be less or equal than MaxOverlays.
mode
Determines how to retreive the image, possible values are:
Mode Description
RasterGetSetOverlayImageMode.Copy A copy of the overlay image is retrieved from the overlay list.
RasterGetSetOverlayImageMode.NoCopy The actual overlay image is retrieved. No copy is made. You should be careful when modifying the returned overlay image because you can modify/invalidate the entry in the overlay bitmap list.
RasterGetSetOverlayImageMode.Move The actual overlay image is retrieved. The image is also removed from the overlay list. This is recommended over RasterGetSetOverlayImageMode.NoCopy.
index
The index of the overlay being retrieved. This index is zero-based and should be less or equal than MaxOverlays.
mode
Determines how to retreive the image, possible values are:
Mode Description
RasterGetSetOverlayImageMode.Copy A copy of the overlay image is retrieved from the overlay list.
RasterGetSetOverlayImageMode.NoCopy The actual overlay image is retrieved. No copy is made. You should be careful when modifying the returned overlay image because you can modify/invalidate the entry in the overlay bitmap list.
RasterGetSetOverlayImageMode.Move The actual overlay image is retrieved. The image is also removed from the overlay list. This is recommended over RasterGetSetOverlayImageMode.NoCopy.
Gets the overlay image for the specified index. Supported in Silverlight, Windows Phone 7

Syntax

Visual Basic (Declaration) 
Public Function GetOverlayImage( _
   ByVal index As Integer, _
   ByVal mode As RasterGetSetOverlayImageMode _
) As RasterImage
Visual Basic (Usage)Copy Code
Dim instance As RasterImage
Dim index As Integer
Dim mode As RasterGetSetOverlayImageMode
Dim value As RasterImage
 
value = instance.GetOverlayImage(index, mode)
C# 
public RasterImage GetOverlayImage( 
   int index,
   RasterGetSetOverlayImageMode mode
)
C++/CLI 
public:
RasterImage^ GetOverlayImage( 
   int index,
   RasterGetSetOverlayImageMode mode
)

Parameters

index
The index of the overlay being retrieved. This index is zero-based and should be less or equal than MaxOverlays.
mode
Determines how to retreive the image, possible values are:
Mode Description
RasterGetSetOverlayImageMode.Copy A copy of the overlay image is retrieved from the overlay list.
RasterGetSetOverlayImageMode.NoCopy The actual overlay image is retrieved. No copy is made. You should be careful when modifying the returned overlay image because you can modify/invalidate the entry in the overlay bitmap list.
RasterGetSetOverlayImageMode.Move The actual overlay image is retrieved. The image is also removed from the overlay list. This is recommended over RasterGetSetOverlayImageMode.NoCopy.

Return Value

A RasterImage object that represents the overlay image of the specified index.

Example

Visual BasicCopy Code
Public Sub GetOverlayImageExample()
      Dim codecs As RasterCodecs = New RasterCodecs()
      ' load an image and set an overlay
      Dim image As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE2.DCM"), 0, CodecsLoadByteOrder.BgrOrGray, 1, 1)
      Dim imageOverlay1 As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "ULAY1.BMP"), 1, CodecsLoadByteOrder.Rgb, 1, 1)
      Dim imageOverlay2 As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "ULAY1.BMP"), 1, CodecsLoadByteOrder.Rgb, 1, 1)
      image.SetOverlayImage(0, imageOverlay1, RasterGetSetOverlayImageMode.Copy)
      image.SetOverlayImage(1, imageOverlay2, RasterGetSetOverlayImageMode.Copy)

      ' update the attributes of one of the overlays
      Dim attributes As RasterOverlayAttributes = image.GetOverlayAttributes(0, RasterGetSetOverlayAttributesFlags.Color Or RasterGetSetOverlayAttributesFlags.Flags Or RasterGetSetOverlayAttributesFlags.Origin Or RasterGetSetOverlayAttributesFlags.BitIndex)

      attributes.Color = New RasterColor(255, 255, 255)
      attributes.AutoPaint = True
      attributes.AutoProcess = True
      attributes.Origin = New LeadPoint(5, 5)
      attributes.BitPosition = image.BitsPerPixel - 1

      image.UpdateOverlayAttributes(0, attributes, RasterGetSetOverlayAttributesFlags.Color Or RasterGetSetOverlayAttributesFlags.Flags Or RasterGetSetOverlayAttributesFlags.Origin Or RasterGetSetOverlayAttributesFlags.BitIndex)


      Dim count As Integer = image.OverlayCount
      Dim i As Integer = 0
      Do While i < count
         Dim overlayTest As RasterImage = image.GetOverlayImage(i, RasterGetSetOverlayImageMode.NoCopy)
         Try
            Dim fileName As String = String.Format(Path.Combine(LEAD_VARS.ImagesDir, "overlay{0}_copy.bmp"), i)
            codecs.Save(overlayTest, fileName, RasterImageFormat.Bmp, 1)
         Finally
            CType(overlayTest, IDisposable).Dispose()
         End Try
         i += 1
      Loop

      image.Dispose()
      imageOverlay1.Dispose()
      imageOverlay2.Dispose()
      codecs.Dispose()
   End Sub

Public NotInheritable Class LEAD_VARS
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class
C#Copy Code
public void GetOverlayImageExample()
   {
      RasterCodecs codecs = new RasterCodecs();
      // load an image and set an overlay
      RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "IMAGE2.DCM"), 0, CodecsLoadByteOrder.BgrOrGray, 1, 1);
      RasterImage imageOverlay1 = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "ULAY1.BMP"), 1, CodecsLoadByteOrder.Rgb, 1, 1);
      RasterImage imageOverlay2 = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "ULAY1.BMP"), 1, CodecsLoadByteOrder.Rgb, 1, 1);
      image.SetOverlayImage(0, imageOverlay1, RasterGetSetOverlayImageMode.Copy);
      image.SetOverlayImage(1, imageOverlay2, RasterGetSetOverlayImageMode.Copy);

      // update the attributes of one of the overlays
      RasterOverlayAttributes attributes = image.GetOverlayAttributes(0,
         RasterGetSetOverlayAttributesFlags.Color |
         RasterGetSetOverlayAttributesFlags.Flags |
         RasterGetSetOverlayAttributesFlags.Origin |
         RasterGetSetOverlayAttributesFlags.BitIndex);

      attributes.Color = new RasterColor(255, 255, 255);
      attributes.AutoPaint = true;
      attributes.AutoProcess = true;
      attributes.Origin = new LeadPoint(5, 5);
      attributes.BitPosition = image.BitsPerPixel - 1;

      image.UpdateOverlayAttributes(
         0,
         attributes,
         RasterGetSetOverlayAttributesFlags.Color |
         RasterGetSetOverlayAttributesFlags.Flags |
         RasterGetSetOverlayAttributesFlags.Origin |
         RasterGetSetOverlayAttributesFlags.BitIndex);


      int count = image.OverlayCount;
      for(int i = 0; i < count; i++)
      {
         using(RasterImage overlayTest = image.GetOverlayImage(i, RasterGetSetOverlayImageMode.NoCopy))
         {               
            string fileName = string.Format(Path.Combine(LEAD_VARS.ImagesDir,"overlay{0}_copy.bmp"), i);
            codecs.Save(overlayTest, fileName, RasterImageFormat.Bmp, 1);
         }
      }

      image.Dispose();
      imageOverlay1.Dispose();
      imageOverlay2.Dispose();
      codecs.Dispose();
   }

static class LEAD_VARS
{
   public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}
SilverlightCSharpCopy Code
public void GetOverlayImageExample(RasterImage image, RasterImage imageOverlay1, RasterImage imageOverlay2, Stream destStream1, Stream destStream2)
{
   // for this sample:
   //  image         == 24-bit image (image1.cmp)
   //  imageOverlay1 == 1-bit image (ulay1.bmp)
   //  imageOverlay2 == 1-bit image (ulay2.bmp)
   image.SetOverlayImage(0, imageOverlay1, RasterGetSetOverlayImageMode.Copy);
   image.SetOverlayImage(1, imageOverlay2, RasterGetSetOverlayImageMode.Copy);
   // update the attributes of one of the overlays
   RasterOverlayAttributes attributes = image.GetOverlayAttributes(0,
      RasterGetSetOverlayAttributesFlags.Color |
      RasterGetSetOverlayAttributesFlags.Flags |
      RasterGetSetOverlayAttributesFlags.Origin |
      RasterGetSetOverlayAttributesFlags.BitIndex);

   attributes.Color = new RasterColor(255, 255, 255);
   attributes.AutoPaint = true;
   attributes.AutoProcess = true;
   attributes.Origin = new LeadPoint(5, 5);
   attributes.BitPosition = image.BitsPerPixel - 1;

   image.UpdateOverlayAttributes(
      0,
      attributes,
      RasterGetSetOverlayAttributesFlags.Color |
      RasterGetSetOverlayAttributesFlags.Flags |
      RasterGetSetOverlayAttributesFlags.Origin |
      RasterGetSetOverlayAttributesFlags.BitIndex);

   RasterCodecs codecs = new RasterCodecs();
   int count = image.OverlayCount;
   Debug.Assert(count == 2);

   RasterImage overlayTest = image.GetOverlayImage(0, RasterGetSetOverlayImageMode.NoCopy);
   codecs.Save(overlayTest, destStream1, RasterImageFormat.Png, 1);
   overlayTest = image.GetOverlayImage(0, RasterGetSetOverlayImageMode.NoCopy);
   codecs.Save(overlayTest, destStream2, RasterImageFormat.Png, 1);

   image.Dispose();
   overlayTest.Dispose();
   imageOverlay1.Dispose();
   imageOverlay2.Dispose();
}
SilverlightVBCopy Code
Public Sub GetOverlayImageExample(ByVal image As RasterImage, ByVal imageOverlay1 As RasterImage, ByVal imageOverlay2 As RasterImage, ByVal destStream1 As Stream, ByVal destStream2 As Stream)
   ' for this sample:
   '  image         == 24-bit image (image1.cmp)
   '  imageOverlay1 == 1-bit image (ulay1.bmp)
   '  imageOverlay2 == 1-bit image (ulay2.bmp)
   image.SetOverlayImage(0, imageOverlay1, RasterGetSetOverlayImageMode.Copy)
   image.SetOverlayImage(1, imageOverlay2, RasterGetSetOverlayImageMode.Copy)
   ' update the attributes of one of the overlays
   Dim attributes As RasterOverlayAttributes = image.GetOverlayAttributes(0, RasterGetSetOverlayAttributesFlags.Color Or RasterGetSetOverlayAttributesFlags.Flags Or RasterGetSetOverlayAttributesFlags.Origin Or RasterGetSetOverlayAttributesFlags.BitIndex)

   attributes.Color = New RasterColor(255, 255, 255)
   attributes.AutoPaint = True
   attributes.AutoProcess = True
   attributes.Origin = New LeadPoint(5, 5)
   attributes.BitPosition = image.BitsPerPixel - 1

   image.UpdateOverlayAttributes(0, attributes, RasterGetSetOverlayAttributesFlags.Color Or RasterGetSetOverlayAttributesFlags.Flags Or RasterGetSetOverlayAttributesFlags.Origin Or RasterGetSetOverlayAttributesFlags.BitIndex)

   Dim codecs As RasterCodecs = New RasterCodecs()
   Dim count As Integer = image.OverlayCount
   Debug.Assert(count = 2)

   Dim overlayTest As RasterImage = image.GetOverlayImage(0, RasterGetSetOverlayImageMode.NoCopy)
   codecs.Save(overlayTest, destStream1, RasterImageFormat.Png, 1)
   overlayTest = image.GetOverlayImage(0, RasterGetSetOverlayImageMode.NoCopy)
   codecs.Save(overlayTest, destStream2, RasterImageFormat.Png, 1)

   image.Dispose()
   overlayTest.Dispose()
   imageOverlay1.Dispose()
   imageOverlay2.Dispose()
End Sub

Remarks

This method is available in the (Document/Medical only) Toolkits.

This method can be used to get a copy of the overlay image (RasterGetSetOverlayImageMode.Copy) or to get the image without making a copy (RasterGetSetOverlayImageMode.NoCopy or RasterGetSetOverlayImageMode.Move).

The quickest way to get the overlay image is to avoid making a copy. For more information on using RasterGetSetOverlayImageMode.NoCopy, refer to the "Remarks" section of SetOverlayImage.

For more information, refer to Overlay Overview.

Requirements

Target Platforms: Silverlight, Windows XP, Windows Server 2003 family, Windows Server 2008 family, Windows Vista, Windows 7, MAC OS/X (Intel Only), Windows Phone 7

See Also