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Programming / Document Viewing / Creating an image from the highlighted region within the GdViewer

Creating an image from the highlighted region within the GdViewer

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Here we will demonstrate how to create an image from the area defined by the highlighted region located on the top of a document displayed within the GdViewer object. Highlighted regions are one of the special features of GdPicture. They can be easily used to specify areas and highlight them only using the mouse.

Copy Code 
'We assume that GdPicture has been correctly installed and unlocked.

'We assume the GdViewer object called GdViewer1 has been created and painted on the form.

Dim oGdPictureImaging As New GdPictureImaging

'Loading the image from a file.

Dim currentImageID As Integer = oGdPictureImaging.CreateGdPictureImageFromFile("C:\\Image.tif")

'Checking if the image resource has been loaded correctly.

If oGdPictureImaging.GetStat() <> GdPictureStatus.OK

   MessageBox.Show("The image can't be loaded. Error: " + oGdPictureImaging.GetStat().ToString(), "Drawing regions Example", MessageBoxButtons.OK, MessageBoxIcon.Error)

Else

   'Displaying the image in the GdViewer.

   GdViewer1.DisplayFromGdPictureImage(currentImageID)

End If

'We will keep the current image for further use, see below.



Dim selectedImageID As Integer = 0 'A new image we are going to create.

'On the Mouse UP event on the GdViewer, get a highlighted region coordinates based on the rectangle of selection of the GdViewer.

'If no rectangle of selection is painted on the GdViewer, this event will do nothing.

Public Sub Draw_Region(ByVal eventSender As System.Object, ByVal eventArgs As System.EventArgs) Handles GdViewer1.MouseUp

   'Initializing variables to hold the position of the rectangle of selection on the document.

   Dim leftArea As Integer, topArea As Integer, widthArea As Integer, heightArea As Integer

   'Checking if a rectangle of selection has been painted on the GdViewer.

   If GdViewer1.IsRect() Then

      'Getting the location of the selection on the document.

      GdViewer1.GetRectCoordinatesOnDocument(leftArea, topArea, widthArea, heightArea)

      'Creating the image from the highlighted region.

      selectedImageID = oGdPictureImaging.CreateClonedGdPictureImageArea(currentImageID, leftArea, topArea, widthArea, heightArea)

      GdViewer1.DisplayFromGdPictureImage(selectedImageID)

   End If

End Sub



'Do not forget to release and dispose both images!

oGdPictureImaging.ReleaseGdPictureImage(currentImageID);

oGdPictureImaging.ReleaseGdPictureImage(selectedImageID);

oGdPictureImaging.Dispose();
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//We assume that GdPicture has been correctly installed and unlocked.

//We assume the GdViewer object called GdViewer1 has been created and painted on the form.

GdPictureImaging oGdPictureImaging = new GdPictureImaging();

//Loading the image from a file.

int currentImageID = oGdPictureImaging.CreateGdPictureImageFromFile("C:\\Image.tif");

//Checking if the image resource has been loaded correctly.

if (oGdPictureImaging.GetStat() != GdPictureStatus.OK)

{

   MessageBox.Show("The image can't be loaded. Error: " + oGdPictureImaging.GetStat().ToString(), "Drawing regions Example", MessageBoxButtons.OK, MessageBoxIcon.Error);

}

else

{

   //Displaying the image in the GdViewer.

   GdViewer1.DisplayFromGdPictureImage(currentImageID);

}

//We will keep the current image for further use, see below.



int selectedImageID = 0; //A new image we are going to create.

//On the Mouse UP event on the GdViewer, get a highlighted region coordinates based on the rectangle of selection of the GdViewer.

//If no rectangle of selection is painted on the GdViewer, this event will do nothing.

public void Mouse_UP_Draw_Region(System.Object eventSender, System.EventArgs eventArgs)

{

   //Initializing variables to hold the position of the rectangle of selection on the document.

   int leftArea = 0;

   int topArea = 0;

   int widthArea = 0;

   int heightArea = 0;

   //Checking if a rectangle of selection has been painted on the GdViewer.

   if (GdViewer1.IsRect())

   {

      //Getting the location of the selection on the document.

      GdViewer1.GetRectCoordinatesOnDocument(ref leftArea, ref topArea, ref widthArea, ref heightArea);

      //Creating the image from the highlighted region.

      selectedImageID = oGdPictureImaging.CreateClonedGdPictureImageArea(currentImageID, leftArea, topArea, widthArea, heightArea);

      GdViewer1.DisplayFromGdPictureImage(selectedImageID);

   }

}



// Do not forget to release and dispose both images!

oGdPictureImaging.ReleaseGdPictureImage(currentImageID);

oGdPictureImaging.ReleaseGdPictureImage(selectedImageID);

oGdPictureImaging.Dispose();