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BlankPageDetectorCommand Class

Summary

Detects whether an image is a blank page. This command is available in the Document/Medical Toolkits.

Syntax

Java

Objective-C

WinRT C#

C++

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

Public Class BlankPageDetectorCommand  
   Inherits Leadtools.Imageprocessing.Leadtools.ImageProcessing.RasterCommand 
   Implements Leadtools.Imageprocessing.Leadtools.ImageProcessing.IRasterCommand

public sealed class BlankPageDetectorCommand : Leadtools.Imageprocessing.Leadtools.ImageProcessing.IRasterCommand

@interface LTBlankPageDetectorCommand : LTRasterCommand

public class BlankPageDetectorCommand extends RasterCommand

function Leadtools.ImageProcessing.Core.BlankPageDetectorCommand()

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

Remarks

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-bit or 16-bit grayscale or 48-bit or 64-bit color images (Exception: Image format not recognized).
This command supports unsigned 8-bit data images, but not signed ones.
This command does not support 32-bit grayscale images.
To load a 24-bit color image in Silverlight, set the UseWriteableBitmap property to false.

In Silverlight 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.

Example

Run the BlankPageDetectorCommand on an image and determine whether it is blank.

WinRT C#

Silverlight C#

Silverlight VB

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing.Core 
 
    
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

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Core; 
 
       
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"; 
}

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Core; 
 
       
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"); 
 
}

using Leadtools; 
using Leadtools.Examples; 
using Leadtools.Codecs; 
using Leadtools.ImageProcessing.Core; 
 
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(); 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.ImageProcessing.Core 
 
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