BlankPageDetectorCommand Class

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

public class BlankPageDetectorCommand : Leadtools.ImageProcessing.RasterCommand, Leadtools.ImageProcessing.IRasterCommand

'Declaration
 
Public Class BlankPageDetectorCommand 
   Inherits Leadtools.ImageProcessing.RasterCommand
   Implements Leadtools.ImageProcessing.IRasterCommand

'Usage
 
Dim instance As BlankPageDetectorCommand

public sealed class BlankPageDetectorCommand : Leadtools.ImageProcessing.IRasterCommand

function Leadtools.ImageProcessing.Core.BlankPageDetectorCommand()

public ref class BlankPageDetectorCommand : public Leadtools.ImageProcessing.RasterCommand, Leadtools.ImageProcessing.IRasterCommand

For various reasons, documents being scanned can contain a significant number of blank pages. Disk storage space for the scanned items can be reduced if such pages can be removed before the documents are stored. This command detects whether a page is blank and returns an accuracy value. It can detect blank pages (despite noise, bleed-through, or lines) with high precision and speed.
This command does not support 12- or 16-bit grayscale or 48- or 64-bit color images (Exception: Image format not recognized).
This command does not support signed data images (Exception: Signed image data not supported).
This command does not support 32-bit grayscale images.
For Silverlight and Windows Phone, to load a 24-bit color images, set the Leadtools.Codecs.CodecsLoadOptions.UseWriteableBitmap property to false.

In Silverlight and Windows Phone versions of LEADTOOLS, this image processing command will fail if the image data for the RasterImage object is stored internally using a Silverlight WriteableBitmap object. For more information, refer to Image Processing Command Limitations in Silverlight.

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

Public Sub BlankPageDetectorCommandExample()
   Dim codecs As New RasterCodecs()
   codecs.ThrowExceptionsOnInvalidImages = True

   Dim leadImage As RasterImage = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Clean.tif"))

   ' Prepare the command
   Dim command As BlankPageDetectorCommand = New BlankPageDetectorCommand
     'Determine whether the image is blank.
   command.Flags = BlankPageDetectorCommandFlags.DetectNoisyPage

   command.Run(leadImage)
   MessageBox.Show(" Is Blank   : " & command.IsBlank & "\n Accuracy : " & (command.Accuracy * 1.0 / 100) & "%", "Blank Page Detection Results")


End Sub

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

public void BlankPageDetectorCommandExample()
   {
      // Load an image
      RasterCodecs codecs = new RasterCodecs();
      codecs.ThrowExceptionsOnInvalidImages = true;

      RasterImage image = codecs.Load(Path.Combine(LEAD_VARS.ImagesDir, "Clean.tif"));

      // Prepare the command
      BlankPageDetectorCommand command = new BlankPageDetectorCommand();
      //Determine whether the image is a blank page
      command.Flags = BlankPageDetectorCommandFlags.DetectNoisyPage;
      command.Run(image);

      MessageBox.Show(" Is Blank   : " + command.IsBlank + "\n Accuracy : " + (command.Accuracy * 1.0 / 100) + "%", "Blank Page Detection Results");

   }

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

function BlankPageDetectorCommandExample()
{
   var codecs = new Leadtools.Codecs.RasterCodecs();
   codecs.throwExceptionsOnInvalidImages = true;

   // Load the image
   var srcFileName = "Assets\\Clean.tif";
   return Tools.AppInstallFolder().getFileAsync(srcFileName).then(function (loadFile) {
      return codecs.loadAsync(Leadtools.LeadStreamFactory.create(loadFile));
   }).then(function (image){
      // Prepare the command
      with (Leadtools.ImageProcessing.Core) {
         var command = new BlankPageDetectorCommand();
         //Determine whether the image is a blank page
         command.flags = BlankPageDetectorCommandFlags.detectNoisyPage;
         command.run(image);

         console.error(" Is Blank   : " + command.isBlank + "\n Accuracy : " + (command.accuracy * 1.0 / 100) + "% ", "Blank Page Detection Results");
      }
   });
}

[TestMethod]
public async Task BlankPageDetectorCommandExample()
{
   // Load an image
   RasterCodecs codecs = new RasterCodecs();
   codecs.ThrowExceptionsOnInvalidImages = true;
   // Load the image
   string srcFileName = @"Assets\Clean.tif";
   StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(srcFileName);
   RasterImage image = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile));

   // Prepare the command
   BlankPageDetectorCommand command = new BlankPageDetectorCommand();
   //Determine whether the image is a blank page
   command.Flags = BlankPageDetectorCommandFlags.DetectNoisyPage;
   command.Run(image);

   Debug.WriteLine(" Is Blank   : " + command.IsBlank + "\n Accuracy : " + (command.Accuracy * 1.0 / 100) + "%", "Blank Page Detection Results");

}

public void BlankPageDetectorCommandExample(RasterImage image)
{
   // Prepare the command
   BlankPageDetectorCommand command = new BlankPageDetectorCommand();
   //Determine whether the image is a blank page
   command.Flags = BlankPageDetectorCommandFlags.DetectNoisyPage;
   command.Run(image);
   Debug.WriteLine(" Is Blank   : " + command.IsBlank + "\n Accuracy : " + (command.Accuracy * 1.0 / 100) + "%", "Blank Page Detection Results", MessageBoxButton.OK);

   image.Dispose();
}

Public Sub BlankPageDetectorCommandExample(ByVal image As RasterImage)
   ' Prepare the command
   Dim command As BlankPageDetectorCommand = New BlankPageDetectorCommand()
   'Determine whether the image is a blank page
   command.Flags = BlankPageDetectorCommandFlags.DetectNoisyPage
   command.Run(image)
   Debug.WriteLine(" Is Blank   : " & command.IsBlank + Constants.vbLf & " Accuracy : " & (command.Accuracy * 1.0 / 100) & "%", _
                   "Blank Page Detection Results", MessageBoxButton.OK)

   image.Dispose()
End Sub

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

BlankPageDetectorCommand Members
Leadtools.ImageProcessing.Core Namespace
Introduction to Image Processing With LEADTOOLS
DeskewCommand Class
DespeckleCommand Class
LineRemoveCommand Class
AutoCropCommand Class