CreateMaskFromRegion Method

Creates a 1-bit mask image from the region that is defined in the image.

Syntax

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

public RasterImage CreateMaskFromRegion()

'Declaration
 
Public Function CreateMaskFromRegion() As RasterImage

'Usage
 
Dim instance As RasterImage
Dim value As RasterImage
 
value = instance.CreateMaskFromRegion()

public RasterImage CreateMaskFromRegion()

 function Leadtools.RasterImage.CreateMaskFromRegion()

public:
RasterImage^ CreateMaskFromRegion();

Return Value

The newly created RasterImage which will be updated with a 1-bit, black-and-white image, where pixels from the region are white, and all others are black.

Remarks

For more information, refer to Implementing Transparency.

For more information, refer to Creating a Region.

For more information, refer to Saving A Region.

For more information, refer to Working with the Existing Region.

Example

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

Public Sub CreateMaskFromRegionExample()
      Dim codecs As RasterCodecs = New RasterCodecs()

      Dim srcFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp")
      Dim destFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1_CreateMaskFromRegion.bmp")

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

      ' Posterize the image to decrease the number of colors
      Dim posterize As PosterizeCommand = New PosterizeCommand(16)
      posterize.Run(image)

      ' Specify a pixel in the upper left of the displayed image
      Dim pt As LeadPoint = New LeadPoint(image.ImageWidth \ 8, image.ImageHeight \ 8)

      ' Adjust the point in case the view perspective is not TopLeft
      pt = image.PointToImage(RasterViewPerspective.TopLeft, pt)

      ' Get the color of the specified pixel
      Dim regionColor As RasterColor = image.GetPixelColor(pt.Y, pt.X)

      ' Create a region that includes all pixels of that color
      image.AddColorToRegion(regionColor, RasterRegionCombineMode.Set)

      Dim maskImage As RasterImage = image.CreateMaskFromRegion()

      codecs.Save(maskImage, destFileName, RasterImageFormat.Bmp, 1)

      maskImage.Dispose()
      image.Dispose()
      codecs.Dispose()
   End Sub

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

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

      string srcFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp");
      string destFileName = Path.Combine(LEAD_VARS.ImagesDir, "Image1_CreateMaskFromRegion.bmp");

      // Load the image
      RasterImage image = codecs.Load(srcFileName);

      // Posterize the image to decrease the number of colors
      PosterizeCommand posterize = new PosterizeCommand(16);
      posterize.Run(image);

      // Specify a pixel in the upper left of the displayed image
      LeadPoint pt = new LeadPoint(image.ImageWidth / 8, image.ImageHeight / 8);

      // Adjust the point in case the view perspective is not TopLeft
      pt = image.PointToImage(RasterViewPerspective.TopLeft, pt);

      // Get the color of the specified pixel
      RasterColor regionColor = image.GetPixelColor(pt.Y, pt.X);

      // Create a region that includes all pixels of that color
      image.AddColorToRegion(regionColor, RasterRegionCombineMode.Set);

      RasterImage maskImage = image.CreateMaskFromRegion();

      codecs.Save(maskImage, destFileName, RasterImageFormat.Bmp, 1);

      maskImage.Dispose();
      image.Dispose();
      codecs.Dispose();
   }

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

RasterImageExamples.prototype.CreateMaskFromRegionExample = function ( )
{
   Tools.SetLicense ( ) ;
   with (Leadtools) {
      with (Leadtools.Codecs) {
         var codecs = new RasterCodecs();

         var srcFileName = "Assets\\Image1.cmp";
         var destFileName = "Image1_CreateMaskFromRegion.bmp";
         var image;
         var maskImage;
         // Load the image
         return Tools.AppInstallFolder().getFileAsync(srcFileName).then(function (loadFile) {
            return codecs.loadAsync(LeadStreamFactory.create(loadFile))
         })
               .then(function (img) {
                  image = img;

                  // Posterize the image to decrease the number of colors
                  var posterize = new Leadtools.ImageProcessing.Color.PosterizeCommand(16);
                  posterize.run(image);

                  // Specify a pixel in the upper left of the displayed image
                  var pt = LeadPointHelper.create(image.imageWidth / 8, image.imageHeight / 8);

                  // Adjust the point in case the view perspective is not TopLeft
                  pt = image.pointToImage(RasterViewPerspective.topLeft, pt);

                  // Get the color of the specified pixel
                  var regionColor = image.getPixelColor(pt.Y, pt.X);

                  // Create a region that includes all pixels of that color
                  image.addColorToRegion(regionColor, RasterRegionCombineMode.set);

                  maskImage = image.createMaskFromRegion();

                  return Tools.AppLocalFolder().createFileAsync(destFileName)
               })
               .then(function (saveFile) {
                  var saveStream = LeadStreamFactory.create(saveFile);
                  return codecs.saveAsync(image, saveStream, RasterImageFormat.bmp, 24)
               })
               .then(function () {

                  maskImage.close();
                  image.close();
                  codecs.close();
               });
      }
   }
}

[TestMethod]
public async Task CreateMaskFromRegionExample()
{
   RasterCodecs codecs = new RasterCodecs();
   string srcFileName = @"Assets\Image1.cmp";
   string destFileName = @"Image1_CreateMaskFromRegion.bmp";

   // Load the image
   StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName);
   RasterImage image = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile));

   // Posterize the image to decrease the number of colors
   PosterizeCommand posterize = new PosterizeCommand(16);
   posterize.Run(image);

   // Specify a pixel in the upper left of the displayed image
   LeadPoint pt = LeadPointHelper.Create(image.ImageWidth / 8, image.ImageHeight / 8);

   // Adjust the point in case the view perspective is not TopLeft
   pt = image.PointToImage(RasterViewPerspective.TopLeft, pt);

   // Get the color of the specified pixel
   RasterColor regionColor = image.GetPixelColor(pt.Y, pt.X);

   // Create a region that includes all pixels of that color
   image.AddColorToRegion(regionColor, RasterRegionCombineMode.Set);

   RasterImage maskImage = image.CreateMaskFromRegion();

   StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(destFileName);
   ILeadStream saveStream = LeadStreamFactory.Create(saveFile);
   await codecs.SaveAsync(image, saveStream, RasterImageFormat.Bmp, 24);

   maskImage.Dispose();
   image.Dispose();
   codecs.Dispose();
}

public void CreateMaskFromRegionExample(RasterImage image, Stream destStream)
{
   // Posterize the image to decrease the number of colors
   PosterizeCommand posterize = new PosterizeCommand(16);
   posterize.Run(image);
   // Specify a pixel in the upper left of the displayed image
   LeadPoint pt = new LeadPoint(image.ImageWidth / 8, image.ImageHeight / 8);

   // Adjust the point in case the view perspective is not TopLeft
   pt = image.PointToImage(RasterViewPerspective.TopLeft, pt);

   // Get the color of the specified pixel
   RasterColor regionColor = image.GetPixelColor(pt.Y, pt.X);

   // Create a region that includes all pixels of that color
   image.AddColorToRegion(regionColor, RasterRegionCombineMode.Set);

   RasterImage maskImage = image.CreateMaskFromRegion();

   RasterCodecs codecs = new RasterCodecs();
   codecs.Save(maskImage, destStream, RasterImageFormat.Png, 0);

   maskImage.Dispose();
   image.Dispose();
}

Public Sub CreateMaskFromRegionExample(ByVal image As RasterImage, ByVal destStream As Stream)
   ' Posterize the image to decrease the number of colors
   Dim posterize As PosterizeCommand = New PosterizeCommand(16)
   posterize.Run(image)
   ' Specify a pixel in the upper left of the displayed image
   Dim pt As LeadPoint = New LeadPoint(image.ImageWidth / 8, image.ImageHeight / 8)

   ' Adjust the point in case the view perspective is not TopLeft
   pt = image.PointToImage(RasterViewPerspective.TopLeft, pt)

   ' Get the color of the specified pixel
   Dim regionColor As RasterColor = image.GetPixelColor(pt.Y, pt.X)

   ' Create a region that includes all pixels of that color
   image.AddColorToRegion(regionColor, RasterRegionCombineMode.Set)

   Dim maskImage As RasterImage = image.CreateMaskFromRegion()

   Dim codecs As RasterCodecs = New RasterCodecs()
   codecs.Save(maskImage, destStream, RasterImageFormat.Png, 0)

   maskImage.Dispose()
   image.Dispose()
End Sub

Requirements

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

RasterImage Class
RasterImage Members