IOcrOmrOptions Interface

Visual Basic
C#
WinRT C#
WinRT JavaScript
C++

public interface IOcrOmrOptions

'Declaration
 
Public Interface IOcrOmrOptions

'Usage
 
Dim instance As IOcrOmrOptions

public interface IOcrOmrOptions

function Leadtools.Forms.Ocr.IOcrOmrOptions()

public interface class IOcrOmrOptions

OMR stands for Optical Mark Recognition. For more information refer to Using OMR in LEADTOOLS .NET OCR.

You can get the instance of the IOcrOmrOptions interface currently used in the engine with the IOcrSpellCheckManager.OmrOptions property.

With the IOcrOmrOptions interface, you can change the following OMR settings:

Change the frame detection method using the IOcrOmrOptions.FrameDetectionMethod property. Frames stand for the checkbox that may exist around OMR fields.
Change the sensitivity of the OMR detection engine using the IOcrOmrOptions.Sensitivity property.
Change the characters to use as a replacement for unfilled and filled OMR marks in the output document (for example, in a PDF file) using the IOcrOmrOptions.GetStateRecognitionCharacter and IOcrOmrOptions.SetStateRecognitionCharacter methods. Note that outputting OMR characters in final document is not supported in native engine formats.

After you call IOcrPage.Recognize, all the OMR zones in the page will have the OMR properties updated as follows:

Property	Description
OcrZone.OmrState	Either OcrOmrZoneState.Filled if the mark is recognized to be filled or checked, or OcrOmrZoneState.Unfilled if the mark is recognized to be unfilled or unchecked.
OcrZone.OmrConfidence	A number between 0 and 100 (where 100 is maximum confidence) that specifies the OCR engine confidence in the recognition status in OcrZone.OmrState.

The OMR zones of a page are zones with the following properties:

Property	Value
OcrZone.FillMethod	Set to OcrZoneFillMethod.Omr
OcrZone.RecognitionModule	Set to OcrZoneRecognitionModule.Omr

All LEADTOOLS OCR engines support OMR. However, there is no current support for auto-detecting OMR zones in a page, you have to add the OMR zones manually to the page by setting their boundary (through OcrZone.Bounds, the fill method and recognition module as described above and adding the zone to the page using the IOcrPage.Zones collection before calling IOcrPage.Recognize.

To use OMR in LEADTOOLS, you need a special key to unlock the OMR capabilities. For more information, refer to Unlocking Special LEAD Features.

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

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Private Sub OcrOmrExample()
      ' Create an instance of the engine
      Using ocrEngine As IOcrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Plus, False)
         ' Start the engine using default parameters
         ocrEngine.Startup(Nothing, Nothing, Nothing, Nothing)
         ' We will use Mixed.tif shipped with LEADTOOLS in the Images folder. This image has 3 OMR check marks
         Dim tifFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "Mixed.tif")

         ' Create an OCR document
         Using ocrDocument As IOcrDocument = ocrEngine.DocumentManager.CreateDocument()
            ' Add a page to the document
            Dim ocrPage As IOcrPage = ocrDocument.Pages.AddPage(tifFileName, Nothing)

            ' Add the OMR zones. We calculated the 3 OMR zone boundaries for this image perviously
            Dim omrBounds() As LogicalRectangle = _
            { _
               New LogicalRectangle(484, 98, 84, 78, LogicalUnit.Pixel), _
               New LogicalRectangle(494, 184, 70, 54, LogicalUnit.Pixel), _
               New LogicalRectangle(498, 244, 76, 76, LogicalUnit.Pixel) _
            }

            For Each omrBound As LogicalRectangle In omrBounds
               ' Create a new OMR zone and add it to the page
               Dim zone As New OcrZone()
               zone.ZoneType = OcrZoneType.Text
               zone.FillMethod = OcrZoneFillMethod.Omr
               zone.RecognitionModule = OcrZoneRecognitionModule.Omr
               zone.Bounds = omrBound
               ocrPage.Zones.Add(zone)
            Next

            ' Show how many zones we have and they properties
            Console.WriteLine("Page has {0} zones:", ocrPage.Zones.Count)
            For i As Integer = 0 To ocrPage.Zones.Count - 1
               Dim zone As OcrZone = ocrPage.Zones(i)
               Console.WriteLine("{0}: Type: {1}, Fill method: {2}, Recognition Module: {3}", i + 1, zone.ZoneType, zone.FillMethod, zone.RecognitionModule)
            Next

            ' Change the OMR options (Auto detection of frames with highest sensitivity)
            Dim omrOptions As IOcrOmrOptions = ocrEngine.ZoneManager.OmrOptions
            omrOptions.FrameDetectionMethod = OcrOmrFrameDetectionMethod.Auto
            omrOptions.Sensitivity = OcrOmrSensitivity.Highest

            ' Recognize the page
            Console.WriteLine("Recognizing...")
            ocrPage.Recognize(Nothing)

            ' Now show the OMR zone properties
            For i As Integer = 0 To ocrPage.Zones.Count - 1
               Dim zone As OcrZone = ocrPage.Zones(i)
               Console.WriteLine("{0}: State: {1}, Confidence: {2}", i + 1, zone.OmrState, zone.OmrConfidence)
            Next

            ' Now save the result as PDF using the default characters representation for OMR states (0 for unfilled, 1 for filled)
            Dim pdfFileName1 As String = Path.Combine(LEAD_VARS.ImagesDir, "Omr_Results1.pdf")
            Console.WriteLine("Saving to {0}...", pdfFileName1)
            ocrDocument.Save(pdfFileName1, DocumentFormat.Pdf, Nothing)

            ' Change the character representation for the OMR states to Y for unfilled, and X for filled
            omrOptions.SetStateRecognitionCharacter(OcrOmrZoneState.Unfilled, "Y"c)
            omrOptions.SetStateRecognitionCharacter(OcrOmrZoneState.Filled, "X"c)

            Dim pdfFileName2 As String = Path.Combine(LEAD_VARS.ImagesDir, "Omr_Results2.pdf")
            Console.WriteLine("Saving to {0}...", pdfFileName2)
            ocrDocument.Save(pdfFileName2, 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

Public NotInheritable Class LEAD_VARS
   Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class

private void OcrOmrExample()
   {
      // Create an instance of the engine
      using(IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Plus, false))
      {
         // Start the engine using default parameters
         ocrEngine.Startup(null, null, null, null);
         // We will use Mixed.tif shipped with LEADTOOLS in the Images folder. This image has 3 OMR check marks
         string tifFileName = Path.Combine(LEAD_VARS.ImagesDir, "Mixed.tif");

         // Create an OCR document
         using(IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument())
         {
            // Add a page to the document
            IOcrPage ocrPage = ocrDocument.Pages.AddPage(tifFileName, null);

            // Add the OMR zones. We calculated the 3 OMR zone boundaries for this image perviously
            LogicalRectangle[] omrBounds =
            {
               new LogicalRectangle(484, 98, 84, 78, LogicalUnit.Pixel),
               new LogicalRectangle(494, 184, 70, 54, LogicalUnit.Pixel),
               new LogicalRectangle(498, 244, 76, 76, LogicalUnit.Pixel)
            };

            foreach(LogicalRectangle omrBound in omrBounds)
            {
               // Create a new OMR zone and add it to the page
               OcrZone zone = new OcrZone();
               zone.ZoneType = OcrZoneType.Text;
               zone.FillMethod = OcrZoneFillMethod.Omr;
               zone.RecognitionModule = OcrZoneRecognitionModule.Omr;
               zone.Bounds = omrBound;
               ocrPage.Zones.Add(zone);
            }

            // Show how many zones we have and they properties
            Console.WriteLine("Page has {0} zones:", ocrPage.Zones.Count);
            for(int i = 0; i < ocrPage.Zones.Count; i++)
            {
               OcrZone zone = ocrPage.Zones[i];
               Console.WriteLine("{0}: Type: {1}, Fill method: {2}, Recognition Module: {3}", i + 1, zone.ZoneType, zone.FillMethod, zone.RecognitionModule);
            }

            // Change the OMR options (Auto detection of frames with highest sensitivity)
            IOcrOmrOptions omrOptions = ocrEngine.ZoneManager.OmrOptions;
            omrOptions.FrameDetectionMethod = OcrOmrFrameDetectionMethod.Auto;
            omrOptions.Sensitivity = OcrOmrSensitivity.Highest;

            // Recognize the page
            Console.WriteLine("Recognizing...");
            ocrPage.Recognize(null);

            // Now show the OMR zone properties
            for(int i = 0; i < ocrPage.Zones.Count; i++)
            {
               OcrZone zone = ocrPage.Zones[i];
               Console.WriteLine("{0}: State: {1}, Confidence: {2}", i + 1, zone.OmrState, zone.OmrConfidence);
            }

            // Now save the result as PDF using the default characters representation for OMR states (0 for unfilled, 1 for filled)
            string pdfFileName1 = Path.Combine(LEAD_VARS.ImagesDir, "Omr_Results1.pdf");
            Console.WriteLine("Saving to {0}...", pdfFileName1);
            ocrDocument.Save(pdfFileName1, DocumentFormat.Pdf, null);

            // Change the character representation for the OMR states to Y for unfilled, and X for filled
            omrOptions.SetStateRecognitionCharacter(OcrOmrZoneState.Unfilled, 'Y');
            omrOptions.SetStateRecognitionCharacter(OcrOmrZoneState.Filled, 'X');

            string pdfFileName2 = Path.Combine(LEAD_VARS.ImagesDir, "Omr_Results2.pdf");
            Console.WriteLine("Saving to {0}...", pdfFileName2);
            ocrDocument.Save(pdfFileName2, DocumentFormat.Pdf, null);
         }

         // 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:\Users\Public\Documents\LEADTOOLS Images";
}

private async void OcrOmrExample()
{
   // Create an instance of the engine
   IOcrEngine ocrEngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, false);
   // Start the engine using default parameters
   ocrEngine.Startup(null, null, String.Empty, Tools.OcrEnginePath);

   // We will use Mixed.tif shipped with LEADTOOLS in the Images folder. This image has 3 OMR check marks
   string tifFileName = "Mixed.tif";

   // Create an OCR document
   IOcrDocument ocrDocument = ocrEngine.DocumentManager.CreateDocument();

   // Add a page to the document
   IOcrPage ocrPage = null;
   using (RasterCodecs codecs = new RasterCodecs())
   {
      StorageFile loadFile = await Tools.AppInstallFolder.GetFileAsync(tifFileName);
      using (RasterImage image = await codecs.LoadAsync(LeadStreamFactory.Create(loadFile)))
         ocrPage = ocrDocument.Pages.AddPage(image, null);
   }

   // Add the OMR zones. We calculated the 3 OMR zone boundaries for this image perviously
   LeadRect[] omrBounds =
   {
      LeadRectHelper.Create(484, 98, 84, 78),
      LeadRectHelper.Create(494, 184, 70, 54),
      LeadRectHelper.Create(498, 244, 76, 76)
   };

   foreach(LeadRect omrBound in omrBounds)
   {
      // Create a new OMR zone and add it to the page
      OcrZone zone = new OcrZone();
      zone.ZoneType = OcrZoneType.Text;
      zone.FillMethod = OcrZoneFillMethod.Omr;
      zone.RecognitionModule = OcrZoneRecognitionModule.Omr;
      zone.Bounds = omrBound;
      ocrPage.Zones.Add(zone);
   }

   // Show how many zones we have and they properties
   Debug.WriteLine("Page has {0} zones:", ocrPage.Zones.Count);
   for(int i = 0; i < ocrPage.Zones.Count; i++)
   {
      OcrZone zone = ocrPage.Zones[i];
      Debug.WriteLine("{0}: Type: {1}, Fill method: {2}, Recognition Module: {3}", i + 1, zone.ZoneType, zone.FillMethod, zone.RecognitionModule);
   }

   // Change the OMR options (Auto detection of frames with highest sensitivity)
   IOcrOmrOptions omrOptions = ocrEngine.ZoneManager.OmrOptions;
   omrOptions.FrameDetectionMethod = OcrOmrFrameDetectionMethod.Auto;
   omrOptions.Sensitivity = OcrOmrSensitivity.Highest;

   // Recognize the page
   Debug.WriteLine("Recognizing...");
   ocrPage.Recognize(null);

   // Now show the OMR zone properties
   for(int i = 0; i < ocrPage.Zones.Count; i++)
   {
      OcrZone zone = ocrPage.Zones[i];
      Debug.WriteLine("{0}: State: {1}, Confidence: {2}", i + 1, zone.OmrState, zone.OmrConfidence);
   }

   // Now save the result as PDF using the default characters representation for OMR states (0 for unfilled, 1 for filled)
   string pdfFileName1 = "Omr_Results1.pdf";
   Debug.WriteLine("Saving to {0}...", pdfFileName1);
   StorageFile saveFile = await Tools.AppLocalFolder.CreateFileAsync(pdfFileName1, CreationCollisionOption.ReplaceExisting);
   await ocrDocument.SaveAsync(LeadStreamFactory.Create(saveFile), DocumentFormat.Pdf, null);

   // Change the character representation for the OMR states to Y for unfilled, and X for filled
   omrOptions.SetStateRecognitionCharacter(OcrOmrZoneState.Unfilled, 'Y');
   omrOptions.SetStateRecognitionCharacter(OcrOmrZoneState.Filled, 'X');

   string pdfFileName2 = "Omr_Results2.pdf";
   Debug.WriteLine("Saving to {0}...", pdfFileName2);
   saveFile = await Tools.AppLocalFolder.CreateFileAsync(pdfFileName2, CreationCollisionOption.ReplaceExisting);
   await ocrDocument.SaveAsync(LeadStreamFactory.Create(saveFile), DocumentFormat.Pdf, null);

   // Shutdown the engine
   ocrEngine.Shutdown();
}

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

IOcrOmrOptions Members
Leadtools.Forms.Ocr Namespace
OcrEngineManager Class
OcrEngineType Enumeration
IOcrPageCollection Interface
IOcrZoneCollection Interface
IOcrZoneManager Interface
OcrZone Structure
OcrZoneRecognitionModule Enumeration
OcrZoneFillMethod Enumeration
Programming with the LEADTOOLS .NET OCR
Using OMR in LEADTOOLS .NET OCR
Unlocking Special LEAD Features

Visual Basic
C#
WinRT C#
WinRT JavaScript
C++

public interface IOcrOmrOptions

'Declaration
 
Public Interface IOcrOmrOptions

'Usage
 
Dim instance As IOcrOmrOptions

public interface IOcrOmrOptions

function Leadtools.Forms.Ocr.IOcrOmrOptions()

public interface class IOcrOmrOptions