AddPage(Uri,OcrProgressCallback) Method

IOcrPage AddPage( 
   Uri uri,
   OcrProgressCallback callback
)

'Declaration
 

Overloads Function AddPage( _
   ByVal uri As Uri, _
   ByVal callback As OcrProgressCallback _
) As IOcrPage

'Usage
 

Dim instance As IOcrPageCollection
Dim uri As Uri
Dim callback As OcrProgressCallback
Dim value As IOcrPage
 
value = instance.AddPage(uri, callback)

IOcrPage AddPage( 
   Uri uri,
   OcrProgressCallback callback
)

function Leadtools.Forms.Ocr.IOcrPageCollection.AddPage(Uri,OcrProgressCallback)( 
   uri ,
   callback 
)

IOcrPage^ AddPage( 
   Uri^ uri,
   OcrProgressCallback^ callback
) 

Parameters

uri

A URI containing the path to the image.

callback

Optional callback to show operation progress.

Return Value

This method will load the first page from a raster image stored in a URI and adds it to the OCR document.

The URI can point to a file in a remote HTTP server, UNC or FTP.

To add all or specific range of the pages of a multi-page image file stored in a URI to the OCR document, use the AddPages(Uri uri, int imageFirstPageNumber, int imageLastPageNumber, OcrProgressCallback callback) method.

This method will add the page to the end of the collection if you already have pages in this IOcrPageCollection.

If you passed a RasterCodecs object to the IOcrEngine.Startup, then this method will use the same RasterCodecs object to load the raster image file. If you did not pass a RasterCodecs object, the engine will create an instance the first time one of the add or export page methods is called.

The image file in uri can be any of the file formats supported by LEADTOOLS. For more information, refer to Summary of All Supported Image File Formats.

You can use the OcrProgressCallback to show the operation progress or to abort it. For more information and an example, refer to OcrProgressCallback.

The LEADTOOLS OCR engine supports pages of dots per inch (DPI) values of 150 and greater. If you try to add a page with a DPI of less than 150 then the engine might be able to recognize any data from this page.

Note: The value of the "Recognition.ShareOriginalImage" (only supported by the Advantage OCR engine) setting is not used when calling this method. The engine loads the image(s) and sets them in the pages internally. The original image reference can be obtained from the page using IOcrPage.GetRasterImage(OcrPageType.Original). Sharing the original image minimizes the memory used during OCR operations.

This member only works with memory-based documents and will throw an exception otherwise. For more information, refer to IOcrDocumentManager.CreateDocument and Programming with the LEADTOOLS .NET OCR.

This example will add a raster image stored in an HTTP location to an OCR document.

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

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Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.Forms.Ocr
Imports Leadtools.Forms.DocumentWriters
Imports Leadtools.Forms
Imports Leadtools.ImageProcessing.Core

<TestMethod>
Public Sub AddPageFromUriExample()
   ' Change this URI to the location of the image you want to load
   Dim uri As New Uri(Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.tif"))
   Dim pdfFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.pdf")
   ' Create an instance of the engine
   Using ocrEngine As IOcrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, False)
      ' Start the engine using default parameters
      ocrEngine.Startup(Nothing, Nothing, Nothing, LEAD_VARS.OcrAdvantageRuntimeDir)

      ' Create an OCR document
      Using ocrDocument As IOcrDocument = ocrEngine.DocumentManager.CreateDocument()
         ' Add the image
         ocrDocument.Pages.AddPage(uri, Nothing)

         ' Recognize
         ocrDocument.Pages.Recognize(Nothing)

         ' Save
         ocrDocument.Save(pdfFileName, DocumentFormat.Pdf, Nothing)
      End Using

      ' Shutdown the engine
      ' Note: calling Dispose will also automatically shutdown the engine if it has been started
      ocrEngine.Shutdown()
   End Using
End Sub

Public NotInheritable Class LEAD_VARS
Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
Public Const OcrAdvantageRuntimeDir As String = "C:\LEADTOOLS 19\Bin\Common\OcrAdvantageRuntime"
End Class

using Leadtools;
using Leadtools.Codecs;
using Leadtools.Forms.Ocr;
using Leadtools.Forms.DocumentWriters;
using Leadtools.Forms;
using Leadtools.ImageProcessing.Core;

public void AddPageFromUriExample()
{
   // Change this URI to the location of the image you want to load
   Uri uri = new Uri(@"http://localhost/MyImages/Ocr1.tif");
   string pdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.pdf");
   // Create an instance of the engine
   using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, false))
   {
      // Start the engine using default parameters
      ocrEngine.Startup(null, null, null, LEAD_VARS.OcrAdvantageRuntimeDir);

      // Create an OCR document
      using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument())
      {
         // Add the image
         ocrDocument.Pages.AddPage(uri, null);

         // Recognize
         ocrDocument.Pages.Recognize(null);

         // Save
         ocrDocument.Save(pdfFileName, DocumentFormat.Pdf, null);
      }

      // Shutdown the engine
      // Note: calling Dispose will also automatically shutdown the engine if it has been started
      ocrEngine.Shutdown();
   }
}

static class LEAD_VARS
{
public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
public const string OcrAdvantageRuntimeDir = @"C:\LEADTOOLS 19\Bin\Common\OcrAdvantageRuntime";
}

Target Platforms

Reference

IOcrPageCollection Interface
IOcrPageCollection Members
Overload List
OcrEngineManager Class
OcrEngineType Enumeration
IOcrPage Interface
Programming with the LEADTOOLS .NET OCR
Summary of All Supported Image File Formats