Take the following steps to start a project and to add some code that creates a set of master forms and uses them to recognize a filled form:

1. Start Visual Studio .NET.
2. Choose File->New->Project... from the menu.
3. In the New Project dialog box, choose either "Visual C# Projects" or "Visual Basic Projects" in the Projects Type List, and choose "Windows Application" in the Templates List.
4. Type the project name as "Recognizing A Form" in the Project Name field, and then choose OK. If desired, type a new location for your project or select a directory using the Browse button, and then choose OK.
5. In the "Solution Explorer" window, right-click on the "References" folder, and select "Add Reference…" from the context menu. In the Add Reference dialog box, select the ".NET" tab, browse to the "\LEAD Technologies\LEADTOOLS 17\Bin\DotNet\Win32" folder and select the following DLLs:
   • Leadtools.dll
   • Leadtools.Codecs.dll
   • Leadtools.Codecs.Fax.dll
   • Leadtools.Codecs.Tif.dll
   • Leadtools.Forms.dll
   • Leadtools.Forms.DocumentWriters.dll
   • Leadtools.Forms.Ocr.dll
   • Leadtools.Forms.Ocr.Advantage.dll
   • Leadtools.Forms.Recognition.dll
   • Leadtools.Forms.Recognition.Ocr.dll
6. Add the following lines at the top of the Form1.cs/Form1.vb file:

   [C#]

               using Leadtools;
               using Leadtools.Codecs;
               using Leadtools.Forms;
               using Leadtools.Forms.Ocr;
               using Leadtools.Forms.Recognition;
               using Leadtools.Forms.Recognition.Ocr;
               using System.IO; 
               
   

   [Visual Basic]

               Imports Leadtools
               Imports Leadtools.Codecs
               Imports Leadtools.Forms
               Imports Leadtools.Forms.Ocr 
               Imports Leadtools.Forms.Recognition
               Imports Leadtools.Forms.Recognition.Ocr
               Imports System.IO
               
   

7. Add the following members to the Form1 class:

   [C#]

               //Create the recognition engine
               FormRecognitionEngine recognitionEngine = new FormRecognitionEngine();
               RasterCodecs codecs;
               //Create the OCR Engine to use in the recognition
               IOcrEngine formsOCREngine;
               
   

   [Visual Basic]

               'Create the recognition engine
               Dim recognitionEngine As FormRecognitionEngine = New FormRecognitionEngine()
               Dim codecs As RasterCodecs
               'Create the OCR Engine to use in the recognition
               Dim formsOCREngine As IOcrEngine
               
   

8. Add the following code to the Load event of the form (Form1_Load()):

   [C#]

               try
                {
                   RasterSupport.Unlock(RasterSupportType.Forms, "Enter valid key here");
                   RasterSupport.Unlock(RasterSupportType.OcrPlus, "Enter valid key here");
                   RasterSupport.Unlock(RasterSupportType.Document, "Enter valid key here");
                   codecs = new RasterCodecs();
                   //Create a LEADTOOLS OCR Plus OCR Engine and start it
                   formsOCREngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, false);
                   formsOCREngine.Startup(codecs, null, null, null);
                   //Add an OCRObjectManager to the recognition engines
                   //ObjectManager collection
                   OcrObjectsManager ocrObjectsManager = new OcrObjectsManager(formsOCREngine);
                   ocrObjectsManager.Engine = formsOCREngine;
                   recognitionEngine.ObjectsManagers.Add(ocrObjectsManager);
                }
                catch (Exception ex)
                {
                   MessageBox.Show(ex.Message);
                } 
                
               
   

   [Visual Basic]

               Try
                  RasterSupport.Unlock(RasterSupportType.Forms, "Enter valid key here")
                  RasterSupport.Unlock(RasterSupportType.OcrPlus, "Enter valid key here")
                  RasterSupport.Unlock(RasterSupportType.Document, "Enter valid key here")
                  codecs = New RasterCodecs()
                  'Create a LEADTOOLS OCR Plus OCR Engine and start it
                  formsOCREngine = OcrEngineManager.CreateEngine(OcrEngineType.Advantage, False)
                  formsOCREngine.Startup(codecs, Nothing, Nothing, Nothing)
                  'Add an OCRObjectManager to the recognition engines
                  'ObjectManager collection
                  Dim ocrObjectsManager As OcrObjectsManager = New OcrObjectsManager(formsOCREngine)
                  ocrObjectsManager.Engine = formsOCREngine
                  recognitionEngine.ObjectsManagers.Add(ocrObjectsManager)
               Catch ex As Exception
                  MessageBox.Show(ex.Message)
               End Try
               
   

9. LEADTOOLS ships several master form images which we will use for this tutorial. The path to the images is hard-coded to the default install location so if you chose another path, you will need to change it accordingly. Add a button to the form and set its Text property to "Create Master Form Attributes" then double-click it and add the following code to its handler:

   [C#]

               try
               {
                  //Get master form filenames
                  //You may need to update the below path to point to the "Leadtools Images\Forms\MasterForm Sets\OCR" directory.
                  string [] masterFileNames = Directory.GetFiles(@"C:\Users\Public\Documents\LEADTOOLS Images\Forms\MasterForm Sets\OCR",
                                                                     "*.tif",
                                                                     SearchOption.AllDirectories);
                  foreach (string masterFileName in masterFileNames)
                  {
                     string formName = Path.GetFileNameWithoutExtension(masterFileName);
                     //Load the master form image
                     RasterImage image = codecs.Load(masterFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, -1);
                     //Create a new master form
                     FormRecognitionAttributes masterFormAttributes = recognitionEngine.CreateMasterForm(formName, Guid.Empty, null);
                     for (int i = 0; i < image.PageCount; i++)
                     {
                        image.Page = i + 1;
                        //Add the master form page to the recognition engine
                        recognitionEngine.AddMasterFormPage(masterFormAttributes, image, null);
                     }
                     //Close the master form and save it's attributes
                     recognitionEngine.CloseMasterForm(masterFormAttributes);
                     File.WriteAllBytes(formName + ".bin", masterFormAttributes.GetData());
                  }
                  MessageBox.Show("Master Form Processing Complete", "Complete");
               }
               catch(Exception ex)
               {
                  MessageBox.Show(ex.Message);
               }
               
   

   [Visual Basic]

                
               Try
                  'Get master form filenames
                  'You may need to update the below path to point to the "Leadtools Images\Forms\MasterForm Sets\OCR" directory.
                  Dim masterFileNames As String() = Directory.GetFiles("C:\Users\Public\Documents\LEADTOOLS Images\Forms\MasterForm Sets\OCR",
                                                                           "*.tif",
                                                                           SearchOption.AllDirectories)
                  For Each masterFileName As String In masterFileNames
                     Dim formName As String = Path.GetFileNameWithoutExtension(masterFileName)
                     'Load the master form image 
                     Dim image As RasterImage = codecs.Load(masterFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, -1)
                     'Create a new master form
                     Dim masterFormAttributes As FormRecognitionAttributes = recognitionEngine.CreateMasterForm(formName, Guid.Empty, Nothing)
                     Dim i As Integer = 0
                     Do While i < image.PageCount
                        image.Page = i + 1
                        'Add the master form page to the recognition engine
                        recognitionEngine.AddMasterFormPage(masterFormAttributes, image, Nothing)
                        i += 1
                     Loop
                     'Close the master form and save it's attributes
                     recognitionEngine.CloseMasterForm(masterFormAttributes)
                     File.WriteAllBytes(formName & ".bin", masterFormAttributes.GetData())
                  Next masterFileName
                  MessageBox.Show("Master Form Processing Complete", "Complete")
               Catch ex As Exception 
                  MessageBox.Show(ex.Message)
               End Try
               
   

10. LEADTOOLS ships several filled form images for each master form which we will use for this tutorial. Add a button to the form and set its Text property to "Recognize Form", then double-click it and add the following code to its handler:

    [C#]

                try
                {
                   //For this tutorial, we will use the sample W9 sample filled form.
                   //You may need to update the below path to point to "\LEADTOOLS Images\Forms\Images\W9_OCR_Filled.tif".
                   string formToRecognize = @"C:\Users\Public\Documents\LEADTOOLS Images\Forms\Images\W9_OCR_Filled.tif";
                   RasterImage image = codecs.Load(formToRecognize, 0, CodecsLoadByteOrder.BgrOrGray, 1, -1);
                   //Load the image to recognize
                   FormRecognitionAttributes filledFormAttributes = recognitionEngine.CreateForm(null);
                   for (int i = 0; i < image.PageCount; i++)
                   {
                      image.Page = i + 1;
                      //Add each page of the filled form to the recognition engine
                      recognitionEngine.AddFormPage(filledFormAttributes, image, null);
                   }
                   recognitionEngine.CloseForm(filledFormAttributes);
                   string resultMessage = "The form could not be recognized";
                   //Compare the attributes of each master form to the attributes of the filled form
                   string[] masterFileNames = Directory.GetFiles(Application.StartupPath, "*.bin");
                   foreach (string masterFileName in masterFileNames)
                   {
                      FormRecognitionAttributes masterFormAttributes = new FormRecognitionAttributes();
                      masterFormAttributes.SetData(File.ReadAllBytes(masterFileName));
                      FormRecognitionResult recognitionResult = recognitionEngine.CompareForm(masterFormAttributes, filledFormAttributes, null);
                      //In this example, we consider a confidence equal to or greater
                      //than 90 to be a match
                      if(recognitionResult.Confidence >= 80)
                      {
                         resultMessage = String.Format("This form has been recognized as a {0}", Path.GetFileNameWithoutExtension(masterFileName));
                         break;
                      }
                   }
                   MessageBox.Show(resultMessage, "Recognition Results");
                }
                catch (Exception ex)
                {
                   MessageBox.Show(ex.Message);
                }
                
    

    [Visual Basic]

                Try
                   'For this tutorial, we will use the sample W9 sample filled form.
                   'You may need to update the below path to point to "\LEADTOOLS Images\Forms\Images\W9_OCR_Filled.tif".
                   Dim formToRecognize As String = "C:\Users\Public\Documents\LEADTOOLS Images\Forms\Images\W9_OCR_Filled.tif"
                   Dim image As RasterImage = codecs.Load(formToRecognize, 0, CodecsLoadByteOrder.BgrOrGray, 1, -1)
                   'Load the image to recognize
                   Dim filledFormAttributes As FormRecognitionAttributes = recognitionEngine.CreateForm(Nothing)
                   Dim i As Integer = 0
                   Do While i < image.PageCount image.Page = i + 1
                      'Add each page of the filled form to the recognition engine
                      recognitionEngine.AddFormPage(filledFormAttributes, image, Nothing)
                      i += 1
                   Loop
                   recognitionEngine.CloseForm(filledFormAttributes)
                   Dim resultMessage As String = "The form could not be recognized"
                   'Compare the attributes of each master form to the attributes of the filled form
                   Dim masterFileNames As String() = Directory.GetFiles(Application.StartupPath, "*.bin")
                   For Each masterFileName As String In masterFileNames
                      Dim masterFormAttributes As FormRecognitionAttributes = New FormRecognitionAttributes()
                      masterFormAttributes.SetData(File.ReadAllBytes(masterFileName))
                      Dim recognitionResult As FormRecognitionResult = recognitionEngine.CompareForm(masterFormAttributes, filledFormAttributes, Nothing)
                      'In this example, we consider a confidence equal to or greater than 90 to be a match
                      If recognitionResult.Confidence >= 80 Then
                         resultMessage = String.Format("This form has been recognized as a {0}", Path.GetFileNameWithoutExtension(masterFileName))
                         Exit For 
                      End If
                   Next masterFileName 
                   MessageBox.Show(resultMessage, "Recognition Results")
                Catch ex As Exception
                      MessageBox.Show(ex.Message)
                End Try 
                
    

11. Add the below clean-up code to the FormClosing event handler:

    [C#]

                 if (formsOCREngine != null && formsOCREngine.IsStarted)
                    formsOCREngine.Shutdown();
                 
                
    

    [Visual Basic]

                If Not formsOCREngine Is Nothing AndAlso formsOCREngine.IsStarted
                   Then formsOCREngine.Shutdown()
                End If 
                
    

12. Run the project and test it. Click the "Create Master Form Attributes" button first which will enumerate all master form images in the directory and save each of their attributes to the application directory. Next, click the "Recognize Form" button which will load a sample form image, generate its attributes, compare them to each master forms attributes, and display the results.

    NOTE: If you encounter an "Invalid File Format" or "Feature Not Supported" exception, please refer to the topic Invalid File Format/Feature Not Supported.

 

 

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