←Select platform

IsMultiThreadedSupported Property

Summary
Gets a value that indicates whether multi-threading is supported in this IOcrAutoRecognizeManager.
Syntax
C#
Objective-C
C++/CLI
Python
public bool IsMultiThreadedSupported { get; } 
@property (nonatomic, assign, readonly) BOOL isMultiThreadedSupported 
property bool IsMultiThreadedSupported { 
   bool get(); 
} 
IsMultiThreadedSupported # get  (IOcrAutoRecognizeManager) 

Property Value

true if this IOcrAutoRecognizeManager supports multi-threading, otherwise; false.

Remarks

The IOcrAutoRecognizeManager supports converting a single document using multiple threads using the Run, RunJob and RunJobAsync methods. You can enable this feature by setting MaximumThreadsPerJob to 0 (for maximum CPUs/cores) or a value greater than 1.

The LEADTOOLS OCR Module - LEAD Engine uses the system thread pool and does not require a set number of threads. A value of 1 will disable threading and any other value will be treated as "use multi-threading".

Not all OCR engines support multi-threading in this fashion. If multi-threading supported, then IsMultiThreadedSupported will be true and the value of MaximumThreadsPerJob is used.

If the OCR engine does not support multi-threading, then IsMultiThreadedSupported will be false and the value of MaximumThreadsPerJob is not used (ignored).

The following table lists the LEADTOOLS OCR engines and whether they support multi-threading in IOcrAutoRecognizeManager:

OCR Engine

Multi-threaded supported in IOcrAutoRecognizeManager
OcrEngineType.LEAD/> Win32 (x86) version Yes
OcrEngineType.LEAD/> x64 version Yes

Some OCR engine types support creating multi-threaded documents by creating one IOcrEngine and multiple IOcrDocument or IOcrAutoRecognizeJob each in its own dedicated threads. For more information, refer to Multi-Threading with LEADTOOLS OCR.

Example
C#
using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Ocr; 
using Leadtools.Document.Writer; 
using Leadtools.Forms.Common; 
using Leadtools.WinForms; 
 
public class RunJobExample 
{ 
   // Number of documents that are pending 
   private int _documentsPending; 
   // Event to trigger when all documents are finished 
   private AutoResetEvent _allDocumentsFinishedEvent; 
 
      public void Start() 
   { 
      string imagesDirectory = LEAD_VARS.ImagesDir; 
      string documentsDirectory = Path.Combine(LEAD_VARS.ImagesDir, "RunJobExample"); 
 
      // Create the output (documents) directory 
      if (!Directory.Exists(documentsDirectory)) 
      { 
         Directory.CreateDirectory(documentsDirectory); 
      } 
 
      // Get all TIF files in input (images) directory 
      string[] imageFileNames = Directory.GetFiles(imagesDirectory, "*.tif"); 
      if (imageFileNames.Length == 0) 
      { 
         Console.WriteLine("No images to OCR"); 
         return; 
      } 
 
      // Create a new OCR engine instance 
      OcrEngineType engineType = OcrEngineType.LEAD; 
      Console.WriteLine(string.Format("Starting up {0} engine", engineType)); 
      using (IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(engineType)) 
      { 
         ocrEngine.Startup(null, null, null, LEAD_VARS.OcrLEADRuntimeDir); 
 
         // Setup document PDF save options: Image/Text with CCITT G4 encoding for B/W 
         DocumentWriter docWriter = ocrEngine.DocumentWriterInstance; 
         PdfDocumentOptions pdfOptions = docWriter.GetOptions(DocumentFormat.Pdf) as PdfDocumentOptions; 
         pdfOptions.ImageOverText = true; 
         pdfOptions.DocumentType = PdfDocumentType.Pdf; 
         pdfOptions.FontEmbedMode = DocumentFontEmbedMode.None; 
         pdfOptions.OneBitImageCompression = OneBitImageCompressionType.FaxG4; 
         docWriter.SetOptions(DocumentFormat.Pdf, pdfOptions); 
 
         // We are going to use multiple-threads, so disable threading in 
         // IOcrAutoRecognizeManager 
         IOcrAutoRecognizeManager autoRecognizeManager = ocrEngine.AutoRecognizeManager; 
         autoRecognizeManager.MaximumThreadsPerJob = 1; 
 
         // Tell the recognize manager to continue on errors 
         autoRecognizeManager.JobErrorMode = OcrAutoRecognizeManagerJobErrorMode.Continue; 
 
         // Instead of using events to trigger when documents are done, 
         // we will use the JobCompleted events of IOcrAutoRecognizeManager 
         // to decrement a counter and trigger one event when the counter reaches 0 
         autoRecognizeManager.JobStarted += new EventHandler<OcrAutoRecognizeRunJobEventArgs>(autoRecognizeManager_JobStarted); 
         autoRecognizeManager.JobCompleted += new EventHandler<OcrAutoRecognizeRunJobEventArgs>(autoRecognizeManager_JobCompleted); 
 
         int count = imageFileNames.Length; 
         _documentsPending = count; 
         _allDocumentsFinishedEvent = new AutoResetEvent(false); 
 
         for (int i = 0; i < count; i++) 
         { 
            // Create the job data 
            string imageFileName = imageFileNames[i]; 
            string name = "Document " + (i + 1).ToString(); 
            Console.WriteLine("Queuing {0} file {1}", name, imageFileName); 
 
            JobData data = new JobData(); 
            data.AutoRecognizeManager = autoRecognizeManager; 
            data.ImageFileName = imageFileName; 
            data.DocumentFileName = Path.Combine(documentsDirectory, Path.GetFileNameWithoutExtension(imageFileName) + ".pdf"); 
            data.JobName = name; 
 
            // Queue this job 
            ThreadPool.QueueUserWorkItem(new WaitCallback(RunJob), data); 
         } 
 
         // Wait for all documents to finish 
         _allDocumentsFinishedEvent.WaitOne(); 
         _allDocumentsFinishedEvent.Close(); 
 
         autoRecognizeManager.JobStarted -= new EventHandler<OcrAutoRecognizeRunJobEventArgs>(autoRecognizeManager_JobStarted); 
         autoRecognizeManager.JobCompleted -= new EventHandler<OcrAutoRecognizeRunJobEventArgs>(autoRecognizeManager_JobCompleted); 
 
         Console.WriteLine("All documents finished, check the result files in {0}", documentsDirectory); 
      } 
   } 
   private void autoRecognizeManager_JobStarted(object sender, OcrAutoRecognizeRunJobEventArgs e) 
   { 
      // This is not strictly needed in this example, we will 
      // use it to show information 
      Console.WriteLine("{0} started...", e.Job.JobData.JobName); 
 
      // Check if we need to abort 
      if (AbortJobs(e.Job)) 
      { 
         // Yes, abort all jobs 
         e.Job.AutoRecognizeManager.AbortAllJobs(); 
      } 
   } 
 
   private void autoRecognizeManager_JobCompleted(object sender, OcrAutoRecognizeRunJobEventArgs e) 
   { 
      string message = string.Format("{0} completed ", e.Job.JobData.JobName); 
 
      IOcrAutoRecognizeJob job = e.Job; 
 
      // Show any errors 
      if (job.Errors.Count == 0) 
      { 
         message += "successfully..."; 
      } 
      else 
      { 
         message += "with errors, first error is " + job.Errors[0].Exception.Message; 
 
         // And save the errors to a text file in the document directory 
         string documentFileName = job.JobData.DocumentFileName; 
         string textPathName = Path.Combine(Path.GetDirectoryName(documentFileName), Path.GetFileNameWithoutExtension(documentFileName) + "_errors.txt"); 
         using (StreamWriter writer = File.CreateText(textPathName)) 
         { 
            writer.WriteLine(job.JobData.JobName); 
            writer.WriteLine("Data:"); 
            writer.WriteLine(" Image file name: " + job.JobData.ImageFileName); 
            writer.WriteLine(" First page number: " + job.JobData.FirstPageNumber); 
            writer.WriteLine(" Last page number: " + job.JobData.LastPageNumber); 
            writer.WriteLine(" Format:" + job.JobData.Format); 
            writer.WriteLine(" Document file name: " + job.JobData.DocumentFileName); 
            writer.WriteLine("Errors:"); 
 
            foreach (OcrAutoRecognizeManagerJobError error in job.Errors) 
            { 
               writer.WriteLine(" Page: {0} during {1}. Error: {2}", error.ImagePageNumber, error.Operation, error.Exception.Message); 
            } 
         } 
      } 
 
      Console.WriteLine(message); 
 
      // Decrement the documents count, when we reach 0, we are done 
      // Since this will be called from multiple threads, we need 
      // to use a thread-safety procedure 
      int pending = Interlocked.Decrement(ref _documentsPending); 
 
      // If we are the last document, wait up main thread 
      if (pending == 0) 
      { 
         _allDocumentsFinishedEvent.Set(); 
      } 
   } 
 
   private class JobData 
   { 
      public IOcrAutoRecognizeManager AutoRecognizeManager; 
      public string ImageFileName; 
      public string DocumentFileName; 
      public string JobName; 
   } 
 
   private void RunJob(object state) 
   { 
      JobData data = state as JobData; 
 
      Console.WriteLine("Running {0}", data.JobName); 
 
      // Run it 
      OcrAutoRecognizeJobData jobData = new OcrAutoRecognizeJobData(data.ImageFileName, DocumentFormat.Pdf, data.DocumentFileName); 
      jobData.JobName = data.JobName; 
      IOcrAutoRecognizeJob job = data.AutoRecognizeManager.CreateJob(jobData); 
      data.AutoRecognizeManager.RunJob(job); 
   } 
 
   private bool AbortJobs(IOcrAutoRecognizeJob ocrJob) 
   { 
      // In your application, you can check if abortion is required, for example, if the user 
      // has pressed the Cancel button on a progress bar or if your service is shutting down. 
 
      // In this example, we will never abort, but you can change this code to return true 
      // upon any condition (or when a specific job is about to start) 
      // and the engine will abort all current and pending jobs 
      return false; 
   } 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
   public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS22\Bin\Common\OcrLEADRuntime"; 
} 
Requirements

Target Platforms

Help Version 22.0.2023.3.31
Products | Support | Contact Us | Intellectual Property Notices
© 1991-2023 LEAD Technologies, Inc. All Rights Reserved.

Leadtools.Ocr Assembly

Products | Support | Contact Us | Intellectual Property Notices
© 1991-2023 LEAD Technologies, Inc. All Rights Reserved.