VintaSoft Imaging .NET SDK 14.0: Documentation for .NET developer
In This Topic
    Identify and recognize a document that contains several completed forms
    In This Topic
    If you want to identify and recognize document that contains several completed forms, you need to do the following steps:
    Here is C#/VB.NET code that demonstrates how to asynchronously identify and recognize several completed forms.
    /// <summary>
    /// Recognizes array of images synchronously.
    /// </summary>
    /// <param name="templateManager">The template manager.</param>
    /// <param name="images">The images.</param>
    public static void RecognizeImagesSync(
        Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager templateManager, 
        Vintasoft.Imaging.VintasoftImage[] images)
    {
        // create template matching command
        Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand templateMatching = 
            new Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand();
        // set minimal confidence
        templateMatching.MinConfidence = 0.6f;
        // set template images
        templateMatching.TemplateImages = templateManager.TemplateImages;
        // create recognition manager
        Vintasoft.Imaging.FormsProcessing.FormRecognitionManager recognitionManager = 
            new Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(
                templateMatching, templateManager);
    
        // if your form template contains OCR fields,
        // make sure OCR engine manager is initialized before recognition
        // (otherwise recognition will return null (Nothing)),
        // see OCR field recognition examples
    
        // subscribe to ImageRecognitionError event to output recognition errors
        recognitionManager.ImageRecognitionError += manager_ImageRecognitionError;
        // recognize the images
        Vintasoft.Imaging.FormsProcessing.FormRecognitionResult[] recognitionResults = recognitionManager.Recognize(images);
        // unsubscribe from ImageRecognitionError event
        recognitionManager.ImageRecognitionError -= manager_ImageRecognitionError;
        // for each recognition result
        for (int i = 0; i < recognitionResults.Length; i++)
        {
            System.Console.WriteLine(string.Format(
                "Image {0} of {1}:",
                i + 1,
                recognitionResults.Length));
            System.Console.WriteLine();
    
            Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult = recognitionResults[i];
    
            // if recognition failed with error (see ImageRecognitionError event handler output)
            if (recognitionResult == null)
                continue;
    
            // get the result of image comparison
            Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult imageCompareResult =
                recognitionResult.TemplateMatchingResult.ImageCompareResult;
            // if result is not reliable
            if (!imageCompareResult.IsReliable)
            {
                // matching template is not found
                System.Console.WriteLine("Matching template is not found.");
            }
            else
            {
                // get recognized page
                Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage recognizedPage = recognitionResult.RecognizedPage;
                // write page info
                System.Console.WriteLine(string.Format(
                    "Matching template: {0}; confidence: {1:F1}%.",
                    recognizedPage.Name,
                    imageCompareResult.Confidence * 100));
    
                // get form field count
                if (recognizedPage.Items.Count == 0)
                {
                    System.Console.WriteLine("No form fields were recognized.");
                }
                else
                {
                    System.Console.WriteLine(string.Format(
                        "Recognized form field count: {0}",
                        recognizedPage.Items.Count));
                    // for each recognized form field
                    foreach (Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField recognizedField in recognizedPage.Items)
                    {
                        // write field info
                        System.Console.WriteLine(string.Format(
                            "  Name: {0}; value: {1}; confidence: {2:F1}%",
                            recognizedField.Name,
                            recognizedField.Value,
                            recognizedField.Confidence * 100));
                    }
                }
            }
    
            System.Console.WriteLine();
            System.Console.WriteLine();
        }
    }
    
    /// <summary>
    /// Handles the ImageRecognitionError event of the FormRecognitionManager.
    /// </summary>
    static void manager_ImageRecognitionError(object sender, 
        Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs e)
    {
        System.Console.WriteLine(e.Exception.Message);
    }
    
    ''' <summary>
    ''' Recognizes array of images synchronously.
    ''' </summary>
    ''' <param name="templateManager">The template manager.</param>
    ''' <param name="images">The images.</param>
    Public Shared Sub RecognizeImagesSync(templateManager As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormTemplateManager, images As Vintasoft.Imaging.VintasoftImage())
        ' create template matching command
        Dim templateMatching As New Vintasoft.Imaging.FormsProcessing.TemplateMatching.TemplateMatchingCommand()
        ' set minimal confidence
        templateMatching.MinConfidence = 0.6F
        ' set template images
        templateMatching.TemplateImages = templateManager.TemplateImages
        ' create recognition manager
        Dim recognitionManager As New Vintasoft.Imaging.FormsProcessing.FormRecognitionManager(templateMatching, templateManager)
    
        ' if your form template contains OCR fields,
        ' make sure OCR engine manager is initialized before recognition
        ' (otherwise recognition will return null (Nothing)),
        ' see OCR field recognition examples
    
        ' subscribe to ImageRecognitionError event to output recognition errors
        AddHandler recognitionManager.ImageRecognitionError, AddressOf manager_ImageRecognitionError
        ' recognize the images
        Dim recognitionResults As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult() = recognitionManager.Recognize(images)
        ' unsubscribe from ImageRecognitionError event
        RemoveHandler recognitionManager.ImageRecognitionError, AddressOf manager_ImageRecognitionError
        ' for each recognition result
        For i As Integer = 0 To recognitionResults.Length - 1
            System.Console.WriteLine(String.Format("Image {0} of {1}:", i + 1, recognitionResults.Length))
            System.Console.WriteLine()
    
            Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = recognitionResults(i)
    
            ' if recognition failed with error (see ImageRecognitionError event handler output)
            If recognitionResult Is Nothing Then
                Continue For
            End If
    
            ' get the result of image comparison
            Dim imageCompareResult As Vintasoft.Imaging.FormsProcessing.TemplateMatching.ImageImprintCompareResult = recognitionResult.TemplateMatchingResult.ImageCompareResult
            ' if result is not reliable
            If Not imageCompareResult.IsReliable Then
                ' matching template is not found
                System.Console.WriteLine("Matching template is not found.")
            Else
                ' get recognized page
                Dim recognizedPage As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormPage = recognitionResult.RecognizedPage
                ' write page info
                System.Console.WriteLine(String.Format("Matching template: {0}; confidence: {1:F1}%.", recognizedPage.Name, imageCompareResult.Confidence * 100))
    
                ' get form field count
                If recognizedPage.Items.Count = 0 Then
                    System.Console.WriteLine("No form fields were recognized.")
                Else
                    System.Console.WriteLine(String.Format("Recognized form field count: {0}", recognizedPage.Items.Count))
                    ' for each recognized form field
                    For Each recognizedField As Vintasoft.Imaging.FormsProcessing.FormRecognition.FormField In recognizedPage.Items
                        ' write field info
                        System.Console.WriteLine(String.Format("  Name: {0}; value: {1}; confidence: {2:F1}%", recognizedField.Name, recognizedField.Value, recognizedField.Confidence * 100))
                    Next
                End If
            End If
    
            System.Console.WriteLine()
            System.Console.WriteLine()
        Next
    End Sub
    
    ''' <summary>
    ''' Handles the ImageRecognitionError event of the FormRecognitionManager.
    ''' </summary>
    Private Shared Sub manager_ImageRecognitionError(sender As Object, e As Vintasoft.Imaging.FormsProcessing.FormRecognitionErrorEventArgs)
        System.Console.WriteLine(e.Exception.Message)
    End Sub