IOcrPageCharacters Interface

Summary

Represents the recognized characters collection of a page.

Syntax

Objective-C

C++/CLI

Java

Python

public interface IOcrPageCharacters : IList<IOcrZoneCharacters>, ICollection<IOcrZoneCharacters>, IEnumerable<IOcrZoneCharacters>, IEnumerable

@interface LTOcrPageCharacters : NSObject<NSFastEnumeration>

public class OcrPageCharacters implements List<OcrZoneCharacters>

public interface class IOcrPageCharacters : public System.Collections.Generic.ICollection<IOcrZoneCharacters>, System.Collections.Generic.IEnumerable<IOcrZoneCharacters>, System.Collections.Generic.IList<IOcrZoneCharacters>, System.Collections.IEnumerable

class IOcrPageCharacters(IList):

Remarks

To get the recognized characters of a page, call IOcrPage.GetRecognizedCharacters after IOcrPage.Recognize.

To update the recognized characters of a page, call IOcrPage.GetRecognizedCharacters before calling IOcrDocument.Save, IOcrDocument.SaveXml.

IOcrPageCharacters implements the standard IList<T>, ICollection<T> and IEnumerable<T> interfaces with items of type IOcrZoneCharacters. Thus each item in the IOcrPageCharacters contains a collection of the character collections of the zones.

The IOcrZoneCharacters interface contains a collection of the characters of a particular zones.

IOcrZoneCharacters also implements IList<T>, ICollection<T> and IEnumerable<T> interfaces but with items of type OcrCharacter. Each item in the IOcrZoneCharacters contains a collection of the characters of the zone.

The IOcrPageCharacters interface also contains the IOcrPageCharacters.UpdateWord method that allow to modify the OCR recognition results by updating or deleting the words before optionally saving the results to the final output document.

delete any word from For example, if you are interested in iterating through the characters of the 2nd zone in the page, you can do the following:

// Get the page characters  
IOcrPageCharacters pageCharacters = ocrPage.GetRecognizedCharacters();  
 
// Get the 2nd zone characters. Note, index is zero-based so 2nd zone is index 1  
// You can also iterate through the pageCharacters collection and find the IOcrZoneCharacters item with ZoneIndex = 1  
IOcrZoneCharacters zoneCharacters = pageCharacters.FindZoneCharacters(1);  
 
// Loop through the characters  
foreach(OcrCharacter ocrCharacter in zoneCharacters)  
{  
   // Do something with ocrCharacter 
}

Example

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Ocr; 
using Leadtools.Forms.Common; 
using Leadtools.Document.Writer; 
using Leadtools.WinForms; 
using Leadtools.Drawing; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
 
public void RecognizedCharactersExample() 
{ 
   // Create an image with some text in it 
   RasterImage image = new RasterImage(RasterMemoryFlags.Conventional, 640, 200, 24, RasterByteOrder.Bgr, RasterViewPerspective.TopLeft, null, IntPtr.Zero, 0); 
   Rectangle imageRect = new Rectangle(0, 0, image.ImageWidth, image.ImageHeight); 
 
   IntPtr hdc = RasterImagePainter.CreateLeadDC(image); 
   using (Graphics g = Graphics.FromHdc(hdc)) 
   { 
      g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; 
      g.FillRectangle(Brushes.White, imageRect); 
 
      using (Font f = new Font("Arial", 20, FontStyle.Regular)) 
         g.DrawString("Normal line", f, Brushes.Black, 0, 0); 
 
      using (Font f = new Font("Arial", 20, FontStyle.Bold)) 
         g.DrawString("Bold, italic and underline", f, Brushes.Black, 0, 40); 
 
      using (Font f = new Font("Courier New", 20, FontStyle.Regular)) 
         g.DrawString("Monospaced line", f, Brushes.Black, 0, 80); 
   } 
 
   RasterImagePainter.DeleteLeadDC(hdc); 
 
   string textFileName = Path.Combine(LEAD_VARS.ImagesDir, "MyImageWithTest.txt"); 
   string pdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "MyImageWithTest.pdf"); 
 
   // Create an instance of the engine 
   using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.LEAD)) 
   { 
      // Start the engine using default parameters 
      ocrEngine.Startup(null, null, null, LEAD_VARS.OcrLEADRuntimeDir); 
 
      // Create an OCR page 
      IOcrPage ocrPage = ocrEngine.CreatePage(image, OcrImageSharingMode.AutoDispose); 
 
      // Recognize this page 
      ocrPage.Recognize(null); 
 
      // Dump the characters into a text file 
      using (StreamWriter writer = File.CreateText(textFileName)) 
      { 
         IOcrPageCharacters ocrPageCharacters = ocrPage.GetRecognizedCharacters(); 
         foreach (IOcrZoneCharacters ocrZoneCharacters in ocrPageCharacters) 
         { 
            // Show the words found in this zone. Get the word boundaries in inches 
            ICollection<OcrWord> words = ocrZoneCharacters.GetWords(); 
            Console.WriteLine("Words:"); 
            foreach (OcrWord word in words) 
               Console.WriteLine("Word: {0}, at {1}, characters index from {2} to {3}", word.Value, word.Bounds, word.FirstCharacterIndex, word.LastCharacterIndex); 
 
            bool nextCharacterIsNewWord = true; 
 
            for (int i = 0; i < ocrZoneCharacters.Count; i++) 
            { 
               OcrCharacter ocrCharacter = ocrZoneCharacters[i]; 
 
               // Capitalize the first letter if this is a new word 
               if (nextCharacterIsNewWord) 
                  ocrCharacter.Code = Char.ToUpper(ocrCharacter.Code); 
 
               writer.WriteLine("Code: {0}, Confidence: {1}, WordIsCertain: {2}, Bounds: {3}, Position: {4}, FontSize: {5}, FontStyle: {6}", 
                  ocrCharacter.Code, 
                  ocrCharacter.Confidence, 
                  ocrCharacter.WordIsCertain, 
                  ocrCharacter.Bounds, 
                  ocrCharacter.Position, 
                  ocrCharacter.FontSize, 
                  ocrCharacter.FontStyle); 
 
               // If the character is bold, make it underline 
               if ((ocrCharacter.FontStyle & OcrCharacterFontStyle.Bold) == OcrCharacterFontStyle.Bold) 
               { 
                  ocrCharacter.FontStyle |= OcrCharacterFontStyle.Italic; 
                  ocrCharacter.FontStyle |= OcrCharacterFontStyle.Underline; 
               } 
 
               // Check if next character is the start of a new word 
               if ((ocrCharacter.Position & OcrCharacterPosition.EndOfWord) == OcrCharacterPosition.EndOfWord || 
                  (ocrCharacter.Position & OcrCharacterPosition.EndOfLine) == OcrCharacterPosition.EndOfLine) 
                  nextCharacterIsNewWord = true; 
               else 
                  nextCharacterIsNewWord = false; 
 
               ocrZoneCharacters[i] = ocrCharacter; 
            } 
         } 
 
         // Replace the characters with the modified one before we save 
         ocrPage.SetRecognizedCharacters(ocrPageCharacters); 
      } 
 
      // Create an OCR document so we can save the results 
      using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument(null, OcrCreateDocumentOptions.AutoDeleteFile)) 
      { 
         // Add the page and dispose it 
         ocrDocument.Pages.Add(ocrPage); 
         ocrPage.Dispose(); 
 
         // Show the recognition results 
         // Set the PDF options to save as PDF/A text only 
         PdfDocumentOptions pdfOptions = ocrEngine.DocumentWriterInstance.GetOptions(DocumentFormat.Pdf) as PdfDocumentOptions; 
         pdfOptions.DocumentType = PdfDocumentType.PdfA; 
         pdfOptions.ImageOverText = false; 
         ocrEngine.DocumentWriterInstance.SetOptions(DocumentFormat.Pdf, pdfOptions); 
 
         ocrDocument.Save(pdfFileName, DocumentFormat.Pdf, null); 
 
         // Open and check the result file, it should contain the following text 
         // "Normal Line" 
         // "Bold And Italic Line" 
         // "Monospaced Line" 
         // With the second line bold and underlined now 
      } 
 
      // 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:\LEADTOOLS23\Resources\Images"; 
   public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS23\Bin\Common\OcrLEADRuntime"; 
}