Overloads Overridable Function ExportPages( _
   ByVal firstPageIndex As Integer, _
   ByVal lastPageIndex As Integer _
) As RasterImage

Visual Basic (Usage)	Copy Code
Dim instance As IOcrPageCollection Dim firstPageIndex As Integer Dim lastPageIndex As Integer Dim value As RasterImage   value = instance.ExportPages(firstPageIndex, lastPageIndex)

virtual RasterImage ExportPages( 
   int firstPageIndex,
   int lastPageIndex
)

virtual RasterImage ExportPages( 
   int firstPageIndex,
   int lastPageIndex
) 

Parameters

firstPageIndex

The zero-based index of the first page to export.

lastPageIndex

The zero-based index of the last page to export. A value of -1 means export up to and including the last page in the OCR document.

Return Value

This example will add a few pages to an OCR document before exporting it back and saving it to disk as a multi-page TIF file.

Visual Basic

Copy Code

Public Sub ExportPagesToRasterImageExample()    ' 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 tifFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "OcrMultiPage.tif"    RasterCodecs.Startup()    Dim codecs As New RasterCodecs()    ' 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()          ' Loop through the images, add them to the document          For i As Integer = 0 To 3             Dim pageFileName As String = Path.Combine(imagesPath, String.Format("Ocr{0}.tif", i + 1))             ocrDocument.Pages.AddPage(pageFileName, Nothing)          Next          Console.WriteLine("OCR document contains {0} pages", ocrDocument.Pages.Count)          ' Export the pages from index 1 to 3 to a RasterImage object          Dim image As RasterImage = ocrDocument.Pages.ExportPages(1, 3)          Console.WriteLine("image contains {0} pages", image.PageCount)          ' Save this image to multi-page TIF file          codecs.Save(image, tifFileName, RasterImageFormat.Tif, 1, 1, -1, 1, CodecsSavePageMode.Overwrite)       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 ExportPagesToRasterImageExample()  {     // 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 tifFileName = LeadtoolsExamples.Common.ImagesPath.Path + "OcrMultiPage.tif";       RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();       // 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())        {           // Loop through the images, add them to the document           for(int i = 0; i < 4; i++)           {              string pageFileName = Path.Combine(imagesPath, string.Format("Ocr{0}.tif", i + 1));              ocrDocument.Pages.AddPage(pageFileName, null);           }             Console.WriteLine("OCR Document contains {0} pages", ocrDocument.Pages.Count);             // Export the pages from index 1 to 3 to a RasterImage object           RasterImage image = ocrDocument.Pages.ExportPages(1, 3);             Console.WriteLine("Image contains {0} pages", image.PageCount);             // Save this image to multi-page TIF file           codecs.Save(image, tifFileName, RasterImageFormat.Tif, 1, 1, -1, 1, CodecsSavePageMode.Overwrite);        }          // 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 image data to the created RasterImage object image. Therefore, after this method returns, there is no relationship between the returned value and the IOcrPage objects inside the OCR document. The returned RasterImage object will need to be disposed.

To export a single page to a RasterImage object, use ExportPage(int pageIndex).

A short-cut to export all the pages in the OCR document to a multi-page RasterImage object is ExportPages(1, -1).

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

Reference