public interface IOcrAutoRecognizeJob : IDisposable
To run an OCR job with IOcrAutoRecognizeManager, first initialize a new OcrAutoRecognizeJobData object with the job's parameters (input image file name, pages, output document format, output document name, optional zones file name, etc.), then use CreateJob to create the IOcrAutoRecognizeJob object. Finally pass this job to either RunJob or RunJobAsync.
The job instance can also be tracked and obtained through the JobStarted, JobProgress and JobCompleted events through the event data (OcrAutoRecognizeRunJobEventArgs.Job or OcrAutoRecognizeJobProgressEventArgs.Job) and the JobOperation event through its event data (OcrAutoRecognizeJobOperationEventArgs.Job.
IOcrAutoRecognizeJob implements the IDisposable interface and you must call the IDisposable.Dispose method on the instance after it is no longer used.
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:\LEADTOOLS23\Resources\Images";
public const string OcrLEADRuntimeDir = @"C:\LEADTOOLS23\Bin\Common\OcrLEADRuntime";
}