OcrException Class

Summary

Represents the exception that is thrown when a runtime error occurs inside the IOcrEngine

Syntax

C++/CLI

Java

Python

[SerializableAttribute()] 
public class OcrException : Exception

public class OcrException extends RuntimeException

[SerializableAttribute()] 
public ref class OcrException : public System.Exception, System.Runtime.InteropServices._Exception, System.Runtime.Serialization.ISerializable

class OcrException(Exception):

Remarks

When a runtime error occurs in the IOcrEngine, an exception of type OcrException is thrown with the engine-specific error code set in the Code member. This error code is engine-specific but a short description can be obtained using the Message property of this class or by using the IOcrEngine.GetErrorCodeString method.

Logic errors such as invalid parameters to methods or invalid operations throw standard .NET exceptions (in this case, ArgumentException and InvalidOperationException respectively Errors caused by loading invalid image files using IOcrEngine.RasterCodecsInstance will throw exceptions of type RasterException. Errors for missing features (support locked) will throw OcrSupportLockedException exceptions. Any other runtime error in the engine will throw an OcrException.

Example

This example shows how to trap various types of exceptions during OCR operations.

Java

using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Ocr; 
using Leadtools.Document.Writer; 
 
public void OcrExceptionExample() 
{ 
   try 
   { 
      // 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); 
 
         string tifFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.tif"); 
         string pdfFileName = Path.Combine(LEAD_VARS.ImagesDir, "Ocr1.pdf"); 
 
         // Create a page 
         // Create an OCR document 
         using (IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument()) 
         { 
            // Add a page to the document 
            IOcrPage ocrPage = ocrDocument.Pages.AddPage(tifFileName, null); 
 
            // Recognize the page 
            // Note, Recognize can be called without calling AutoZone or manually adding zones. The engine will 
            // check and automatically auto-zones the page 
            ocrPage.Recognize(null); 
 
            // Save the document we have as PDF 
            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(); 
      } 
   } 
   catch (OcrSupportLockedException ex) 
   { 
      Console.WriteLine("Support is locked. You need to unlock '{0}' in this engine to use this feature", ex.SupportType); 
   } 
   catch (OcrException ex) 
   { 
      Console.WriteLine("OCR Error\nCode: {0}\nMessage:{1}", ex.Code, ex.Message); 
   } 
   catch (RasterException ex) 
   { 
      Console.WriteLine("LEADTOOLS Error\nCode: {0}\nMessage:{1}", ex.Code, ex.Message); 
   } 
   catch (Exception ex) 
   { 
      Console.WriteLine("System Error\nMessage:{0}", ex.Message); 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS23\Resources\Images"; 
   public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS23\Bin\Common\OcrLEADRuntime"; 
}

 
import static org.junit.Assert.assertTrue; 
 
import java.io.File; 
import java.io.IOException; 
 
import org.junit.*; 
import org.junit.runner.JUnitCore; 
import org.junit.runner.Result; 
import org.junit.runner.notification.Failure; 
 
import leadtools.*; 
import leadtools.document.writer.DocumentFormat; 
import leadtools.ocr.*; 
 
 
public void OcrExceptionExample() { 
   final String LEAD_VARS_OCR_LEAD_RUNTIME_DIR = "C:\\LEADTOOLS23\\Bin\\Common\\OcrLEADRuntime"; 
   final String LEAD_VARS_IMAGES_DIR = "C:\\LEADTOOLS23\\Resources\\Images"; 
 
   try { 
      // Create an instance of the engine 
      OcrEngine ocrEngine = OcrEngineManager.createEngine(OcrEngineType.LEAD); 
 
      // Start the engine using default parameters 
      ocrEngine.startup(null, null, null, LEAD_VARS_OCR_LEAD_RUNTIME_DIR); 
 
      String pdfFileName = combine(LEAD_VARS_IMAGES_DIR, "pdfsegmentation.pdf"); 
      ILeadStream leadStream = LeadStreamFactory.create("C:\\LEADTOOLS23\\Resources\\Images\\Ocr1.tif"); 
 
      // Create a page 
      // Create an OCR document 
      OcrDocument ocrDocument = ocrEngine.getDocumentManager().createDocument(); 
 
      // Add a page to the document 
      OcrPage ocrPage = ocrDocument.getPages().addPage(leadStream, null); 
 
      // Recognize the page 
      // Note, Recognize can be called without calling AutoZone or manually adding 
      // zones. The engine will 
      // check and automatically auto-zones the page 
      ocrPage.recognize(null); 
 
      // Save the document we have as PDF 
      ocrDocument.save(pdfFileName, DocumentFormat.PDF, null); 
      assertTrue("File unsuccessfully saved", new File(pdfFileName).exists()); 
      System.out.printf("Command run, file saved to %s", pdfFileName); 
 
      // Shutdown the engine 
      // Note: calling Dispose will also automatically shutdown the engine if it has 
      // been started 
      ocrEngine.shutdown(); 
 
   } catch (OcrSupportLockedException ex) { 
      System.out.printf( 
         "Support is locked. You need to unlock '%s' in this engine to use this feature", 
         ex.getSupportType() 
      ); 
   } catch (OcrException ex) { 
      System.out.printf( 
         "OCR Error\nCode: %s\nMessage:%s", ex.getCode(), ex.getMessage() 
      ); 
   } catch (RasterException ex) { 
      System.out.printf( 
         "LEADTOOLS Error\nCode: %s\nMessage:%s", ex.getCode(), ex.getMessage() 
      ); 
   } catch (Exception ex) { 
      System.out.printf( 
         "System Error\nMessage:%s", ex.getMessage() 
      ); 
   } 
}