InsertPage(int,string,OcrProgressCallback) Method

Summary

Inserts the image stored in a disk file to the specified location.

Syntax

Objective-C

C++

public IOcrPage InsertPage( 
   int pageIndex, 
   string fileName, 
   OcrProgressCallback callback 
)

Overloads Function InsertPage( _ 
   ByVal pageIndex As Integer, _ 
   ByVal fileName As String, _ 
   ByVal callback As OcrProgressCallback _ 
) As IOcrPage

- (nullable LTOcrPage *)insertPageAtIndex:(NSUInteger)pageIndex 
                                     file:(NSString *)fileName 
                                    error:(NSError **)error

IOcrPage^ InsertPage(  
   int pageIndex, 
   String^ fileName, 
   OcrProgressCallback^ callback 
)

Parameters

pageIndex
The zero-based index at which fileName should be inserted.

fileName
The name of the file containing the image.

callback
Optional callback to show operation progress.

Return Value

The IOcrPage object that define the newly inserted page.

Remarks

This method will load the first page from a raster image file on disk and inserts it to the OCR document at the specified location.

To insert all or specific range of the pages of a multipage image file to the OCR document, use the InsertPages(int pageIndex, string fileName, int imageFirstPageNumber, int imageLastPageNumber, OcrProgressCallback callback) method.

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 fileName 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 LEADTOOLS OCR Module - LEAD 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.

Example

This example will load then insert in reverse order a group of image files from disk.

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Ocr; 
using Leadtools.Document.Writer; 
using Leadtools.Forms.Common; 
using Leadtools.ImageProcessing.Core; 
 
public void InsertPageFromFileExample() 
{ 
   string pdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.pdf"); 
 
   // Load the Ocr1.tif, Ocr2.tif, Ocr3.tif and Ocr4.tif to a single RasterImage object 
   RasterCodecs codecs = new RasterCodecs(); 
 
   // Create an instance of the engine 
   using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD)) 
   { 
      // 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, LEAD_VARS.OcrLEADRuntimeDir); 
 
      // Create an OCR document 
      using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument()) 
      { 
         // Loop through the images, insert them in the reverse order 
         for (int i = 0; i < 4; i++) 
         { 
            string pageFileName = Path.Combine(LEAD_VARS.ImagesDir, string.Format("Ocr{0}.tif", i + 1)); 
            ocrDocument.Pages.InsertPage(0, pageFileName, null); 
         } 
 
         // Recognize 
         ocrDocument.Pages.Recognize(0, 1, 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(); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS21\Resources\Images"; 
   public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS21\Bin\Common\OcrLEADRuntime"; 
}

Imports Leadtools 
Imports Leadtools.Codecs 
Imports Leadtools.Ocr 
Imports Leadtools.Document.Writer 
Imports Leadtools.Forms 
Imports Leadtools.ImageProcessing.Core 
 
Public Sub InsertPageFromFileExample() 
   Dim pdfFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.pdf") 
 
   ' Load the Ocr1.tif, Ocr2.tif, Ocr3.tif and Ocr4.tif to a single RasterImage object 
   Dim codecs As New RasterCodecs() 
 
   ' Create an instance of the engine 
   Using ocrEngine As IOcrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD) 
      ' 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, LEAD_VARS.OcrLEADRuntimeDir) 
 
      ' Create an OCR document 
      Using ocrDocument As IOcrDocument = ocrEngine.DocumentManager.CreateDocument() 
         ' Loop through the images, insert them in the reverse order 
         For i As Integer = 0 To 3 
            Dim pageFileName As String = Path.Combine(LEAD_VARS.ImagesDir, String.Format("Ocr{0}.tif", i + 1)) 
            ocrDocument.Pages.InsertPage(0, pageFileName, Nothing) 
         Next 
 
         ' Recognize 
         ocrDocument.Pages.Recognize(0, 1, 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() 
End Sub 
 
Public NotInheritable Class LEAD_VARS 
   Public Const ImagesDir As String = "C:\LEADTOOLS21\Resources\Images" 
   Public Const OcrLEADRuntimeDir As String = "C:\LEADTOOLS21\Bin\Common\OcrLEADRuntime" 
End Class