VintaSoft Imaging .NET SDK 15.1: Документация для .NET разработчика
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ICR: Распознавание рукописных цифр
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Интеллектуальное распознавание символов (ICR) используется для извлечения рукописного текста из изображений. Это более сложный тип технологии OCR, которая распознает различные стили рукописного ввода и шрифты для интеллектуальной интерпретации данных в формах и физических документах.

Начиная с версии 12.5 VintaSoft OCR .NET Plug-in предоставляет сборку Vintasoft.Imaging.Ocr.ML.dll для распознавания рукописных цифр (символов "0123456789)(+-/") с использованием нейронной сети.
Сборка Vintasoft.Imaging.Ocr.ML.dll выполняет машинное обучение с использованием библиотеки "Microsoft.ML" и имеет ссылки на версию 4.0.0 nuget-пакетов "Microsoft.ML" и "Microsoft.ML.LightGbm".

Сборка Vintasoft.Imaging.Ocr.ML.dll содержит следующие классы для распознавания рукописных цифр:
Также сборку Vintasoft.Imaging.Ocr.ML.dll можно использовать совместно с VintaSoft Forms Processing .NET Plug-in для распознавания рукописных цифр в полях заполненной формы.
Класс OcrFieldTemplate позволяет определить шаблон OCR-поля, содержащего одну строку рукописных цифр.


Вот C#/VB.NET код, который демонстрирует, как распознать одну строку рукописных цифр на изображении с помощью класса HandwrittenDigitsLineRecognizer:
/// <summary>
/// Recognizes the line of handwritten digits using HandwrittenDigitsLineRecognizer class.
/// </summary>
/// <param name="image">The image.</param>
/// <returns>Recognized line.</returns>
public static string RecognizeHandwrittenLineUsingHandwrittenDigitsLineRecognizer(Vintasoft.Imaging.VintasoftImage image)
{
    // create handwritten digits recognizer
    Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsLineRecognizer lineRecognizer = 
        new Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsLineRecognizer(image, "1234567890");

    // recognize line of handwritten digits
    Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsRecognitionResult result = lineRecognizer.RecognizeLine();

    // print result
    for (int i = 0; i < result.Symbols.Length; i++)
        System.Console.WriteLine(string.Format("{0}: {1}%", result.Symbols[i], System.Math.Round(result.Confidences[i] * 100)));

    return result.ToString();
}
''' <summary>
''' Recognizes the line of handwritten digits using HandwrittenDigitsLineRecognizer class.
''' </summary>
''' <param name="image">The image.</param>
''' <returns>Recognized line.</returns>
Public Shared Function RecognizeHandwrittenLineUsingHandwrittenDigitsLineRecognizer(image As Vintasoft.Imaging.VintasoftImage) As String
    ' create handwritten digits recognizer
    Dim lineRecognizer As New Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsLineRecognizer(image, "1234567890")

    ' recognize line of handwritten digits
    Dim result As Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsRecognitionResult = lineRecognizer.RecognizeLine()

    ' print result
    For i As Integer = 0 To result.Symbols.Length - 1
        System.Console.WriteLine(String.Format("{0}: {1}%", result.Symbols(i), System.Math.Round(result.Confidences(i) * 100)))
    Next

    Return result.ToString()
End Function


Вот C#/VB.NET код, который демонстрирует, как распознать одну строку рукописных цифр в области изображения с помощью класса HandwrittenDigitsOcrEngine:
/// <summary>
/// Recognizes the line of handwritten digits.
/// </summary>
/// <param name="image">The image.</param>
/// <returns>Recognized line.</returns>
public static string RecognizeHandwrittenLineUsingHandwrittenDigitsOcrEngine(Vintasoft.Imaging.VintasoftImage image)
{
    // create OCR engine for recognition of handwritten digits
    Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrEngine ocrEngine =
        new Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrEngine();
    
    // create OCR settings for recognition of handwritten digits
    Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrSettings ocrSettings = 
        new Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrSettings();
    ocrSettings.CharWhiteList = "1234567890";
    
    // init OCR engine
    ocrEngine.Init(ocrSettings);

    // recognize line of handwritten digits
    Vintasoft.Imaging.Ocr.Results.OcrPage page = ocrEngine.Recognize(image);
    Vintasoft.Imaging.Ocr.Results.OcrTextRegion textRegion = (Vintasoft.Imaging.Ocr.Results.OcrTextRegion)page.Regions[0];

    // print result
    System.Console.WriteLine(string.Format("{0}: {1}%", textRegion.Text, textRegion.Confidence));
    
    return textRegion.Text;
}
''' <summary>
''' Recognizes the line of handwritten digits.
''' </summary>
''' <param name="image">The image.</param>
''' <returns>Recognized line.</returns>
Public Shared Function RecognizeHandwrittenLineUsingHandwrittenDigitsOcrEngine(image As Vintasoft.Imaging.VintasoftImage) As String
    ' create OCR engine for recognition of handwritten digits
    Dim ocrEngine As New Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrEngine()

    ' create OCR settings for recognition of handwritten digits
    Dim ocrSettings As New Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrSettings()
    ocrSettings.CharWhiteList = "1234567890"

    ' init OCR engine
    ocrEngine.Init(ocrSettings)

    ' recognize line of handwritten digits
    Dim page As Vintasoft.Imaging.Ocr.Results.OcrPage = ocrEngine.Recognize(image)
    Dim textRegion As Vintasoft.Imaging.Ocr.Results.OcrTextRegion = DirectCast(page.Regions(0), Vintasoft.Imaging.Ocr.Results.OcrTextRegion)

    ' print result
    System.Console.WriteLine(String.Format("{0}: {1}%", textRegion.Text, textRegion.Confidence))

    Return textRegion.Text
End Function


Вот C#/VB.NET код, который демонстрирует, как распознать поле с строкой рукописных цифр в заполненной форме:
/// <summary>
/// Recognizes the form with OCR fields, which contain handwritten digits.
/// </summary>
/// <param name="formRecognitionManager">The form recognition manager.</param>
/// <param name="image">The image.</param>
public static void RecognizeHandwrittenDigitsInFilledForm(
    Vintasoft.Imaging.FormsProcessing.FormRecognitionManager formRecognitionManager,
    Vintasoft.Imaging.VintasoftImage image)
{
    // check whether OCR engine manager of the OCR field templates is initialized
    // (this initialization can be moved to the start of your application)
    if (Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager == null)
    {
        // create OCR engine for recognition of handwritten digits
        Vintasoft.Imaging.Ocr.OcrEngine handwrittenDigitsOcrEngine = new Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrEngine();

        // create and set OCR engine manager for the OCR field templates
        Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager =
            new Vintasoft.Imaging.Ocr.OcrEngineManager(handwrittenDigitsOcrEngine);
    }

    // recognize filled form in an image
    Vintasoft.Imaging.FormsProcessing.FormRecognitionResult recognitionResult =
        formRecognitionManager.Recognize(image);

    // 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;
        // 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)
            {
                if (recognizedField is Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField)
                {
                    Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField ocrField =
                        (Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField)recognizedField;
                    // write field info
                    System.Console.WriteLine(string.Format(
                        "  OCR field: name: {0}; value: {1}; confidence: {2:F1}%",
                        ocrField.Name,
                        ocrField.Value,
                        ocrField.Confidence * 100));
                    Vintasoft.Imaging.Ocr.Results.OcrPage ocrResult = ocrField.OcrResult;
                    // get all words
                    Vintasoft.Imaging.Ocr.Results.OcrObject[] words = ocrResult.GetWords(75, 75);
                    // write words info
                    for (int i = 0; i < words.Length; i++)
                    {
                        Vintasoft.Imaging.Ocr.Results.OcrObject word = words[i];
                        System.Console.WriteLine(string.Format(
                            "    OCR word: {0}; confidence: {1:F1}%",
                            word.ToString(),
                            word.Confidence));
                    }
                }
            }
        }
    }
}    
''' <summary>
''' Recognizes the form with OCR fields, which contain handwritten digits.
''' </summary>
''' <param name="formRecognitionManager">The form recognition manager.</param>
''' <param name="image">The image.</param>
Public Shared Sub RecognizeHandwrittenDigitsInFilledForm(formRecognitionManager As Vintasoft.Imaging.FormsProcessing.FormRecognitionManager, image As Vintasoft.Imaging.VintasoftImage)
    ' check whether OCR engine manager of the OCR field templates is initialized
    ' (this initialization can be moved to the start of your application)
    If Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager Is Nothing Then
        ' create OCR engine for recognition of handwritten digits
        Dim handwrittenDigitsOcrEngine As Vintasoft.Imaging.Ocr.OcrEngine = New Vintasoft.Imaging.Ocr.ML.HandwrittenDigits.HandwrittenDigitsOcrEngine()

        ' create and set OCR engine manager for the OCR field templates
        Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrFieldTemplate.OcrEngineManager = New Vintasoft.Imaging.Ocr.OcrEngineManager(handwrittenDigitsOcrEngine)
    End If

    ' recognize filled form in an image
    Dim recognitionResult As Vintasoft.Imaging.FormsProcessing.FormRecognitionResult = formRecognitionManager.Recognize(image)

    ' 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
        ' 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
                If TypeOf recognizedField Is Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField Then
                    Dim ocrField As Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField = DirectCast(recognizedField, Vintasoft.Imaging.FormsProcessing.FormRecognition.Ocr.OcrField)
                    ' write field info
                    System.Console.WriteLine(String.Format("  OCR field: name: {0}; value: {1}; confidence: {2:F1}%", ocrField.Name, ocrField.Value, ocrField.Confidence * 100))
                    Dim ocrResult As Vintasoft.Imaging.Ocr.Results.OcrPage = ocrField.OcrResult
                    ' get all words
                    Dim words As Vintasoft.Imaging.Ocr.Results.OcrObject() = ocrResult.GetWords(75, 75)
                    ' write words info
                    For i As Integer = 0 To words.Length - 1
                        Dim word As Vintasoft.Imaging.Ocr.Results.OcrObject = words(i)
                        System.Console.WriteLine(String.Format("    OCR word: {0}; confidence: {1:F1}%", word.ToString(), word.Confidence))
                    Next
                End If
            Next
        End If
    End If
End Sub