LEADTOOLS OCR (Leadtools.Forms.Ocr assembly)

IOcrPageCollection Interface

Show in webframe
Example 







Members 
Represents the pages of an OCR document object.
Object Model
Syntax
'Usage
 
Dim instance As IOcrPageCollection
@interface LTOcrPageCollection : NSMutableArray
public class OcrPageCollection implements List<OcrPage>
Remarks

IOcrPageCollection holds the pages currently added into an OCR document (IOcrDocument). IOcrDocument through the IOcrDocument.Pages holds a collection of IOcrPage object. Each of these IOcrPage objects contains the raster image used to create it (the image used when the page is loaded or added) and a group of OCR zones for the page either added manually or through auto-zoning.

The IOcrPageCollection interface implements standard .NET ICollection, IList, and IEnumerable interfaces and hence, you can use the member of these interfaces to add, remove, get, set and iterate through the different pages of the OCR document.

The following list contains the major functionality of the IOcrPageCollection interface:

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.

Example
Copy Code  
Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.Forms.Ocr
Imports Leadtools.Forms
Imports Leadtools.Forms.DocumentWriters
Imports Leadtools.WinForms
Imports Leadtools.ImageProcessing.Core
Imports Leadtools.Drawing

Public Sub PageCollectionExamples()
   ' For this example, we need a multi-page TIF file.
   ' Create a muti-page TIF from Ocr1.tif, Ocr2.tif, Ocr3.tif and Ocr4.tif
   Dim imagesPath As String = LEAD_VARS.ImagesDir
   Dim tifFileName As String = Path.Combine(imagesPath, "Ocr.tif")
   If (File.Exists(tifFileName)) Then
      File.Delete(tifFileName)
   End If
   Using codecs As New RasterCodecs()
      For i As Integer = 0 To 3
         Dim pageFileName As String = Path.Combine(imagesPath, String.Format("Ocr{0}.tif", i + 1))
         Using image As RasterImage = codecs.Load(pageFileName)
            codecs.Save(image, tifFileName, RasterImageFormat.CcittGroup4, 1, 1, 1, -1, CodecsSavePageMode.Append)
         End Using
      Next
   End Using

   Dim pdfFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Ocr.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()
         ' Load all the pages of the multi-page tif file we created into the document
         ocrDocument.Pages.AddPages(tifFileName, 1, -1, Nothing)
         Console.WriteLine("{0} pages added to the document", ocrDocument.Pages.Count)

         ' Auto-zone
         ocrDocument.Pages.AutoZone(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 18\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 PageCollectionExamples()
{
   // For this example, we need a multi-page TIF file.
   // Create a muti-page TIF from Ocr1.tif, Ocr2.tif, Ocr3.tif and Ocr4.tif
   string tifFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr.tif");
   if (File.Exists(tifFileName))
      File.Delete(tifFileName);
   using (RasterCodecs codecs = new RasterCodecs())
   {
      for (int i = 0; i < 4; i++)
      {
         string pageFileName = Path.Combine(LEAD_VARS.ImagesDir, string.Format("Ocr{0}.tif", i + 1));
         using (RasterImage image = codecs.Load(pageFileName))
            codecs.Save(image, tifFileName, RasterImageFormat.CcittGroup4, 1, 1, 1, -1, CodecsSavePageMode.Append);
      }
   }

   string pdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr.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())
      {
         // Load all the pages of the multi-page tif file we created into the form
         ocrDocument.Pages.AddPages(tifFileName, 1, -1, null);
         Console.WriteLine("{0} pages added to the document", ocrDocument.Pages.Count);

         // Auto-zone
         ocrDocument.Pages.AutoZone(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 18\Bin\Common\OcrAdvantageRuntime";
}
using Leadtools;
using Leadtools.Codecs;
using Leadtools.Forms.Ocr;
using Leadtools.Forms.DocumentWriters;
using Leadtools.Forms;
using Leadtools.ImageProcessing.Core;

[TestMethod]
public async Task PageCollectionExamples()
{
   // For this example, we need a multi-page TIF file.
   string tifFileName = @"Assets\Ocr1.tif";
   string pdfFileName = "Ocr.pdf";

   // Create an instance of the engine
   IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, false);

   // Start the engine using default parameters
   ocrEngine.Startup(null, null, String.Empty, Tools.OcrEnginePath);

   // Create an OCR document
   IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument();

   // Load all the pages of the multi-page tif file we created into the form
   using (RasterCodecs codecs = new RasterCodecs())
   {
      StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(tifFileName);
      using (RasterImage image = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile)))
      {
         ocrDocument.Pages.AddPage(image, null);
         Debug.WriteLine("{0} pages added to the document", ocrDocument.Pages.Count);
      }
   }

   // Auto-zone
   ocrDocument.Pages.AutoZone(null);

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

   // Save
   StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(pdfFileName, CreationCollisionOption.ReplaceExisting);
   await ocrDocument.SaveAsync(LeadStreamFactory.Create(saveFile), DocumentFormat.Pdf, null);

   // Shutdown the engine
   ocrEngine.Shutdown();
}
Requirements

Target Platforms

See Also

Reference

IOcrPageCollection Members
Leadtools.Forms.Ocr Namespace
OcrEngineManager Class
OcrEngineType Enumeration
IOcrPage Interface
Programming with the LEADTOOLS .NET OCR
Summary of All Supported Image File Formats
Working with OCR Pages

 

 


Products | Support | Contact Us | Copyright Notices
© 2006-2014 All Rights Reserved. LEAD Technologies, Inc.

IOcrPageCollection requires an OCR module license and unlock key. For more information, refer to: Imaging Pro/Document/Medical Features