Overloads Overridable Sub AddPages( _
   ByVal image As RasterImage, _
   ByVal imageFirstPageNumber As Integer, _
   ByVal imageLastPageNumber As Integer, _
   ByVal callback As OcrProgressCallback _
) 

Visual Basic (Usage)	Copy Code
Dim instance As IOcrPageCollection Dim image As RasterImage Dim imageFirstPageNumber As Integer Dim imageLastPageNumber As Integer Dim callback As OcrProgressCallback   instance.AddPages(image, imageFirstPageNumber, imageLastPageNumber, callback)

virtual void AddPages( 
   RasterImage image,
   int imageFirstPageNumber,
   int imageLastPageNumber,
   OcrProgressCallback callback
)

virtual void AddPages( 
   RasterImage image,
   int imageFirstPageNumber,
   int imageLastPageNumber,
   OcrProgressCallback^ callback
) 

Parameters

image

The RasterImage object containing the pages to add.

imageFirstPageNumber

1-based index of the first page in image to add.

imageLastPageNumber

1-based index of the last page in image to add. A value of -1 means add up to and including the last page in image.

callback

Optional callback to show operation progress.

This example will load multiple pages into a RasterImage object then add them to the OCR engine.

Visual Basic

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Public Sub AddMultiPageRasterImageExample()    ' Unlock the support needed for LEADTOOLS Plus OCR engine    RasterSupport.Unlock(RasterSupportType.Document, "Replace with your own key here")    RasterSupport.Unlock(RasterSupportType.OcrPlus, "Replace with your own key here")    RasterSupport.Unlock(RasterSupportType.OcrPlusPdfLeadOutput, "Replace with your own key here")    Dim imagesPath As String = LeadtoolsExamples.Common.ImagesPath.Path    Dim pdfFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "Ocr1.pdf"    ' Load the Ocr1.tif, Ocr2.tif, Ocr3.tif and Ocr4.tif to a single RasterImage object    RasterCodecs.Startup()    Dim codecs As New RasterCodecs()    Dim image As RasterImage = Nothing    For i As Integer = 0 To 3       Dim pageFileName As String = Path.Combine(imagesPath, String.Format("Ocr{0}.tif", i + 1))       Dim tempImage As RasterImage = codecs.Load(pageFileName)       If (image Is Nothing) Then          image = tempImage       Else          image.AddPage(tempImage)       End If    Next    Console.WriteLine("RasterImage has {0} pages", image.PageCount)    ' Create an instance of the engine    Using ocrEngine As IOcrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Plus, False)       ' Since we have a RasterCodecs object, re-use it in the OCR engine. Although       ' this demo will not use it, it is always a good practice       ocrEngine.Startup(codecs, Nothing, Nothing, Nothing)       ' Create an OCR document       Using ocrDocument As IOcrDocument = ocrEngine.DocumentManager.CreateDocument()          ' Add the 2nd and 3rd pages to the document          Console.WriteLine("Adding the pages from 2 to 3 to the document")          ocrDocument.Pages.AddPages(image, 2, 3, Nothing)          Console.WriteLine("OCR document has {0} pages", ocrDocument.Pages.Count)          ' We do not need the image anymore          image.Dispose()          ' 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    codecs.Dispose()    RasterCodecs.Shutdown() End Sub

C#

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public void AddMultiPageRasterImageExample()  {     // Unlock the support needed for LEADTOOLS Plus OCR engine     RasterSupport.Unlock(RasterSupportType.Document, "Replace with your own key here");     RasterSupport.Unlock(RasterSupportType.OcrPlus, "Replace with your own key here");     RasterSupport.Unlock(RasterSupportType.OcrPlusPdfLeadOutput, "Replace with your own key here");     string imagesPath = LeadtoolsExamples.Common.ImagesPath.Path;     string pdfFileName = LeadtoolsExamples.Common.ImagesPath.Path + "Ocr1.pdf";       // Load the Ocr1.tif, Ocr2.tif, Ocr3.tif and Ocr4.tif to a single RasterImage object     RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();       RasterImage image = null;     for(int i = 0; i < 4; i++)     {        string pageFileName = Path.Combine(imagesPath, string.Format("Ocr{0}.tif", i + 1));        RasterImage tempImage = codecs.Load(pageFileName);        if(image == null)           image = tempImage;        else           image.AddPage(tempImage);     }       Console.WriteLine("RasterImage has {0} pages", image.PageCount);       // Create an instance of the engine     using(IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Plus, false))     {        // Since we have a RasterCodecs object, re-use it in the OCR engine. Although        // this demo will not use it, it is always a good practice        ocrEngine.Startup(codecs, null, null, null);          // Create an OCR document        using(IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument())        {           // Add the 2nd and 3rd pages to the document           Console.WriteLine("Adding the pages from 2 to 3 to the document");           ocrDocument.Pages.AddPages(image, 2, 3, null);           Console.WriteLine("Document has {0} pages", ocrDocument.Pages.Count);             // We do not need the image anymore           image.Dispose();             // 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();     }       codecs.Dispose();     RasterCodecs.Shutdown();  }

This method copies the RasterImage object image data into the newly created IOcrPage. Therefore, after this method returns, there is no relationship between image and the IOcrPage inside the OCR document. For example, if you do not need the image object after calling this method, you should dispose it after this method returns.

This method guarantees that no changes will be made to image.

A short-cut to add all the pages of a RasterImage object to the OCR document is AddPages(image, 1, -1, callback).

To add a single page from a RasterImage object, you can use AddPage(RasterImage image, OcrProgressCallback callback).

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

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 LEADTOOLS Plus OCR engine does not support image size greater than A3 paper size (11.7 by 16.5 inches at 300 dpi). Attempting to add an image that has a size greater than A3 will result in an error. For document of size greater than the maximum allowed, you must first resize the image before adding it to the LEADTOOLS Plus OCR engine. The Professional and Advantage engines do not have a restriction on the image size.

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

Reference