Overloads Overridable Sub Startup( _
   ByVal rasterCodecs As RasterCodecs, _
   ByVal documentWriter As DocumentWriter, _
   ByVal workDirectory As String, _
   ByVal startupParameters As String _
) 

Visual Basic (Usage)	Copy Code
Dim instance As IOcrEngine Dim rasterCodecs As RasterCodecs Dim documentWriter As DocumentWriter Dim workDirectory As String Dim startupParameters As String   instance.Startup(rasterCodecs, documentWriter, workDirectory, startupParameters)

virtual void Startup( 
   RasterCodecs rasterCodecs,
   DocumentWriter documentWriter,
   string workDirectory,
   string startupParameters
)

virtual void Startup( 
   RasterCodecs rasterCodecs,
   DocumentWriter documentWriter,
   String^ workDirectory,
   String^ startupParameters
) 

Parameters

rasterCodecs

Optional instance of a RasterCodecs object to be used when loading image files from disk inside the engine. You can pass your own initialized instance of RasterCodecs to be used. The same object will then be used internally by the OCR engine when loading raster image files. Otherwise, pass null (Nothing in Visual Basic) and the IOcrEngine will create and use its own version of RasterCodecs when needed.

documentWriter

Optional instance of a DocumentWriter object to be used when saving OCR documents to disk inside the engine. You can pass your own initialized instance of DocumentWriter to be used. The same object will then be used internally by the OCR engine when saving OCR documents to disk. Otherwise, pass null (Nothing in Visual Basic) and the IOcrEngine will create and use its own version of DocumentWriter when needed.

workDirectory

Optional path to a directory to be used when the engine saves temporary files. The IOcrEngine object will create various temporary files during recognition and document saving processes. It will use the path passed in workDirectory as the location where these temporary files will be created. You can pass null (Nothing in Visual Basic) to let the engine select the temporary directory of the current logged in user (TEMP).

In either case, the value of working directory of the current started IOcrEngine can be obtained through the WorkDirectory property.

The engine automatically deletes any temporary files created. However, if an unexpected error occurs (for example, an unhandled exception), some temporary files may still reside in the work directory after the application exits. A typical application may use a custom directory inside the application path and manually deletes any files that may reside there before calling Startup in case the previous instance of the application exited abnormally.

If the value of the workDirectory parameter is not null (Nothing in Visual Basic), then it must refer to a valid directory that exists in the system and the process that created the engine must have enough access rights to read, write and delete files from this directory.

startupParameters

Optional startup parameter. The value of this parameter depends on the type of this IOcrEngine as follows:

Engine	startupParameters
OcrEngineType.Advantage	The path to the folder containing the OCR engine files. By default, during setup the LEADTOOLS OCR Module setup installs the OCR engine files to "Installation Path\Bin\Common\OcrAdvantageRuntime" where Installation Path is the root folder where the LEADTOOLS for .NET Class Library is installed (for example, C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 16.5). If you pass null (Nothing in Visual Basic) to startupParameters, then the LEADTOOLS OCR engine will look for these extra files in the default installation folder specified above. When you are ready to package your application, you might want to change the location where the LEADTOOLS OCR engine looks for these extra files. You can use this property to do that. Set the path you want before calling the Startup method.
OcrEngineType.Plus	The path to the folder containing the OCR engine files. By default, during setup the LEADTOOLS OCR Module setup installs the OCR engine files to "Installation Path\Bin\Common\OcrPlusRuntime" where Installation Path is the root folder where the LEADTOOLS for .NET Class Library is installed (for example, C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 16.5). If you pass null (Nothing in Visual Basic) to startupParameters, then the LEADTOOLS OCR engine will look for these extra files in the default installation folder specified above. When you are ready to package your application, you might want to change the location where the LEADTOOLS OCR engine looks for these extra files. You can use this property to do that. Set the path you want before calling the Startup method.
OcrEngineType.Professional	The path to the folder containing the OCR engine files. By default, during setup the LEADTOOLS OCR Module setup installs the OCR engine files to "Installation Path\Bin\Common\OcrProfessionalRuntime" where Installation Path is the root folder where the LEADTOOLS for .NET Class Library is installed (for example, C:\Program Files (x86)\LEAD Technologies\LEADTOOLS 16.5). If you pass null (Nothing in Visual Basic) to startupParameters, then the LEADTOOLS OCR engine will look for these extra files in the default installation folder specified above. When you are ready to package your application, you might want to change the location where the LEADTOOLS OCR engine looks for these extra files. You can use this property to do that. Set the path you want before calling the Startup method.

The following example assumes you copied the OCR engine runtime files to C:\MyApp\Ocr.

Visual Basic

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Public Sub StartupEngineExample()    ' 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")    ' Use RasterCodecs to load an image file    ' Note: You can let the engine load the image file directly as shown in the other examples    RasterCodecs.Startup()    Dim codecs As New RasterCodecs()    Dim image As RasterImage = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Ocr1.tif")    ' Assume you coped the engine runtime files to C:\MyApp\Ocr    Dim engineDir As String = "C:\MyApp\Ocr"    ' Store the engine work directory into a path inside our application    Dim workDir As String = "C:\MyApp\OcrTemp"    ' Delete all files in the work directory in case the previous version of our application exited abnormally and    ' the engine did not get the chance to clean all of its temporary files (if any)    Directory.Delete(workDir, True)    ' Re-create the work directory    Directory.CreateDirectory(workDir)    ' Create an instance of the engine    Using ocrEngine As IOcrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Plus, False)       ' Show that the engine has not been started yet       Console.WriteLine("Before calling Startup, IsStarted = " + ocrEngine.IsStarted.ToString())       ' Start the engine using our parameters       ' Since we already have a RasterCodecs object, we can re-use it to save memory and resources       ocrEngine.Startup(codecs, Nothing, workDir, engineDir)       ' Make sure the engine is using our working directory       Console.WriteLine("workDir passed is {0}, the value of WorkDirectory after Startup is {1}", workDir, ocrEngine.WorkDirectory)       ' Show that the engine has started fine       Console.WriteLine("After calling Startup, EngineType is {0}, IsStarted = {1}", ocrEngine.EngineType, ocrEngine.IsStarted)       ' Maks sure the engine is using our own version of RasterCodecs       Debug.Assert(codecs Is ocrEngine.RasterCodecsInstance)       ' Create an OCR document       Using ocrDocument As IOcrDocument = ocrEngine.DocumentManager.CreateDocument()          ' Add the raster image as page to the document          Dim ocrPage As IOcrPage = ocrDocument.Pages.AddPage(image, Nothing)          ' 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(Nothing)          ' Save the document we have as PDF          Dim pdfFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "Ocr1.pdf"          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

C#

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public void StartupEngineExample()  {     // 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");     // Use RasterCodecs to load an image file     // Note: You can let the engine load the image file directly as shown in the other examples     RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();     RasterImage image = codecs.Load(LeadtoolsExamples.Common.ImagesPath.Path + "Ocr1.tif");       // Assume you coped the engine runtime files to C:\MyApp\Ocr     string engineDir = @"C:\MyApp\Ocr";       // Store the engine work directory into a path inside our application     string workDir = @"C:\MyApp\OcrTemp";       // Delete all files in the work directory in case the previous version of our application exited abnormally and     // the engine did not get the chance to clean all of its temporary files (if any)     Directory.Delete(workDir, true);       // Re-create the work directory     Directory.CreateDirectory(workDir);       // Create an instance of the engine     using(IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Plus, false))     {        // Show that the engine has not been started yet        Console.WriteLine("Before calling Startup, IsStarted = " + ocrEngine.IsStarted);          // Start the engine using our parameters        // Since we already have a RasterCodecs object, we can re-use it to save memory and resources        ocrEngine.Startup(codecs, null, workDir, engineDir);          // Make sure the engine is using our working directory        Console.WriteLine("workDir passed is {0}, the value of WorkDirectory after Startup is {1}", workDir, ocrEngine.WorkDirectory);          // Show that the engine has started fine        Console.WriteLine("After calling Startup, EngineType is {0}, IsStarted = {1}", ocrEngine.EngineType, ocrEngine.IsStarted);          // Maks sure the engine is using our own version of RasterCodecs        Debug.Assert(codecs == ocrEngine.RasterCodecsInstance);          // Create an OCR document        using(IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument())        {           // Add the raster image as page to the document           IOcrPage ocrPage = ocrDocument.Pages.AddPage(image, 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           string pdfFileName = LeadtoolsExamples.Common.ImagesPath.Path + "Ocr1.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();     }  }

The Startup method must be called before invoking any other methods or properties in this IOcrEngine.

To check if the engine is started, use the IsStarted property.

You must call Shutdown to shut down the engine and free the memory and resources used.

You can call the Startup method multiple times, only the first call will start the engine while subsequent calls will only increment an internal counter. You must call Shutdown for each Startup called.

The IOcrEngine interface implements IDisposable. It is highly recommended that you call Dispose (or use the using statement in C# or Using statement in Visual Basic) when creating the IOcrEngine instance. The Dispose method will automatically shuts down the engine if it has been started.

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

Reference