RecognitionAlternate.Confidence Property

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RecognitionAlternate.Confidence Property

Gets the level of confidence that a recognizer has in the recognition of a RecognitionAlternate object.

Definition

Visual Basic .NET Public ReadOnly Property Confidence As RecognitionConfidence
C# public RecognitionConfidence Confidence { get; }
Managed C++ public: __property RecognitionConfidence* get_Confidence();

Property Value

Microsoft.Ink.RecognitionConfidence. The level of confidence that a recognizer has in the recognition of a RecognitionAlternate object or of a gesture.

This property is read-only. This property has no default value.

Strong0 Indicates strong confidence in the result or alternate.
Intermediate1 Indicates intermediate confidence in the result or alternate.
Poor2 Indicates poor confidence in the result or alternate.

Exceptions

COMException Leave Site:

Remarks

If the alternate represents a phrase or sentence, the value represents the lowest confidence level of a recognition segment found in the phrase or sentence. However, if the alternate represents a word, the value represents the confidence level of the word.

Note: This property throws an exception if the Recognizer that generates the RecognitionAlternate does not support confidence levels.

Of the Microsoft® recognizers, only the Microsoft English (US) Handwriting Recognizer and the Microsoft Gesture Recognizer support confidence levels. Third party recognizers may or may not support confidence levels.

Examples

[C#]

This C# example defines event handlers for a form, ConfidenceAlternatesForm, to which a Button Leave Site control, theButton, has been added. The sample also defines an InkCollector, theInkCollector, a RecognizerContext, theRecognizerContext, and a RecognitionResult, theRecognitionResult, which are used to collect ink and to perform recognition.

The event handler for the form's load event creates an ink collector and gets a recognizer context for the English (US) language.

The event handler for the button's click event performs recognition on the strokes in the ink collector, divides the strokes along confidence boundaries, and colors the strokes according to their confidence level.

// Declare ink elements and create drawing attributes.
Microsoft.Ink.InkCollector theInkCollector = null;
Microsoft.Ink.RecognizerContext theRecognizerContext = null;
Microsoft.Ink.RecognitionResult theRecognitionResult = null;

Microsoft.Ink.DrawingAttributes theStrongDA =
    new DrawingAttributes(Color.Green);
Microsoft.Ink.DrawingAttributes theIntermediateDA =
    new DrawingAttributes(Color.Goldenrod);
Microsoft.Ink.DrawingAttributes thePoorDA =
    new DrawingAttributes(Color.Red);

// Event handler for the form's Load event.
private void ConfidenceAlternatesForm_Load(object sender, System.EventArgs e)
{
    // Create the ink collector.
    this.theInkCollector = new Microsoft.Ink.InkCollector(this.Handle);
    this.theInkCollector.Enabled = true;

    // Get a recognizer context for the English (US) recognizer.
    foreach (Recognizer theRecognizer in new Recognizers())
    {
        foreach (short lcid in theRecognizer.Languages)
        {
            // 0409 is the LCID for the en-us language.
            if (0x0409 == lcid)
            {
                this.theRecognizerContext = theRecognizer.CreateRecognizerContext();
                break;
            }
        }
        if (null != theRecognizerContext)
        {
            break;
        }
    }
    // Throw an exception if the recognizer is not found.
    if (null == theRecognizerContext)
    {
        throw new ApplicationException("No recognizer found");
    }
}

// Event handler for the button's Click event.
private void theButton_Click(object sender, System.EventArgs e)
{
    // Check for ink before performing recognition.
    if (0 == this.theInkCollector.Ink.Strokes.Count)
    {
        System.Windows.Forms.MessageBox.Show("No ink to recognize.");
        return;
    }

    // Perform recognition on the strokes currently in the ink collector.
    Microsoft.Ink.RecognitionStatus theRecognitionStatus;
    this.theRecognizerContext.Strokes = this.theInkCollector.Ink.Strokes;
    this.theRecognitionResult =
        this.theRecognizerContext.Recognize(out theRecognitionStatus);

    // Check the recognition status.
    if (Microsoft.Ink.RecognitionStatus.NoError != theRecognitionStatus)
    {
        System.Windows.Forms.MessageBox.Show(
            "There was an error recognizing the ink.");
        return;
    }

    // Check for a recognition result.
    if (null == this.theRecognitionResult)
    {
        System.Windows.Forms.MessageBox.Show(
            "No recognition result available.");
        return;
    }

    // Get the confidence alternates collection for the top alternate.
    Microsoft.Ink.RecognitionAlternates theConfidenceAlternates =
        this.theRecognitionResult.TopAlternate.ConfidenceAlternates;

    using (System.Drawing.Graphics g = this.CreateGraphics())
    {
        // Clear the drawing surface
        g.Clear(this.BackColor);

        // For each confidence alternate in the collection:
        foreach(Microsoft.Ink.RecognitionAlternate theAlternate
                    in theConfidenceAlternates)
        {
            // Update the drawing attributes.
            switch (theAlternate.Confidence)
            {
                case Microsoft.Ink.RecognitionConfidence.Strong:
                    theAlternate.Strokes.ModifyDrawingAttributes(
                        theStrongDA);
                    break;
                case Microsoft.Ink.RecognitionConfidence.Intermediate:
                    theAlternate.Strokes.ModifyDrawingAttributes(
                        theIntermediateDA);
                    break;
                case Microsoft.Ink.RecognitionConfidence.Poor:
                    theAlternate.Strokes.ModifyDrawingAttributes(
                        thePoorDA);
                    break;
            }
        }
        // Redraw the ink.
        this.theInkCollector.Renderer.Draw(g, this.theRecognitionResult.Strokes);
    }
}

// Event handler for the form's Closed event.
private void ConfidenceAlternatesForm_Closed(object sender, System.EventArgs e)
{
    // Free the resources for the ink collector, recognizer context, and pens.
    this.theInkCollector.Dispose();
    this.theInkCollector = null;
    this.theRecognizerContext.Dispose();
    this.theRecognizerContext = null;
}

[Visual Basic .NET]

This Microsoft Visual Basic® .NET example defines event handlers for a form, ConfidenceAlternatesForm, to which a Button Leave Site control, theButton, has been added. The sample also defines an InkCollector, theInkCollector, a RecognizerContext, theRecognizerContext, and a RecognitionResult, theRecognitionResult, which are used to collect ink and to perform recognition.

The event handler for the form's load event creates an ink collector and gets a recognizer context for the English (US) language.

The event handler for the button's click event performs recognition on the strokes in the ink collector, divides the strokes along confidence boundaries, and colors the strokes according to their confidence level.

' Declare ink elements and create drawing attributes.
Dim theInkCollector As Microsoft.Ink.InkCollector
Dim theRecognizerContext As Microsoft.Ink.RecognizerContext
Dim theRecognitionResult As Microsoft.Ink.RecognitionResult

Dim theStrongDA As Microsoft.Ink.DrawingAttributes = New DrawingAttributes(Color.Green)
Dim theIntermediateDA As Microsoft.Ink.DrawingAttributes = New DrawingAttributes(Color.Goldenrod)
Dim thePoorDA As Microsoft.Ink.DrawingAttributes = New DrawingAttributes(Color.Red)

' Event handler for the form's Load event.
Private Sub ConfidenceAlternatesForm_Load(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles MyBase.Load

    ' Create the ink collector.
    Me.theInkCollector = New Microsoft.Ink.InkCollector(Me.Handle)
    Me.theInkCollector.Enabled = True

    ' Get a recognizer context for the English (US) recognizer.
    For Each theRecognizer As Recognizer In New Recognizers
        For Each lcid As Short In theRecognizer.Languages
            ' 0409 is the LCID for the en-us language.
            If &H409 = lcid Then
                Me.theRecognizerContext = theRecognizer.CreateRecognizerContext()
                Exit For
            End If
        Next
        If Not (theRecognizerContext Is Nothing) Then
            Exit For
        End If
    Next
    ' Throw an exception if the recognizer is not found.
    If theRecognizerContext Is Nothing Then
        Throw New ApplicationException("No recognizer found")
    End If
End Sub

' Event handler for the "Recognize" button's Click event.
Private Sub theButton_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles theButton.Click

    ' Check for ink before performing recognition.
    If Me.theInkCollector.Ink.Strokes.Count = 0 Then
        System.Windows.Forms.MessageBox.Show("No ink to recognize.")
        Return
    End If

    ' Perform recognition on the strokes currently in the ink collector.
    Dim theRecognitionStatus As Microsoft.Ink.RecognitionStatus
    Me.theRecognizerContext.Strokes = Me.theInkCollector.Ink.Strokes
    Me.theRecognitionResult = _
        Me.theRecognizerContext.Recognize(theRecognitionStatus)

    ' Check for a recognition result.
    If (Me.theRecognitionResult Is Nothing) Then
        System.Windows.Forms.MessageBox.Show("No recognition result available.")
        Return
    End If

    ' Get the confidence alternates collection for the top alternate.
    Dim theConfidenceAlternates As Microsoft.Ink.RecognitionAlternates = _
        Me.theRecognitionResult.TopAlternate.ConfidenceAlternates

    ' Create a temporary graphics object.
    Dim g As System.Drawing.Graphics = Me.CreateGraphics()

    ' Clear the drawing surface
    g.Clear(Me.BackColor)

    ' For each confidence alternate in the collection:
    For Each theAlternate As Microsoft.Ink.RecognitionAlternate _
                In theConfidenceAlternates

        ' Update the drawing attributes.
        Select Case theAlternate.Confidence
            Case RecognitionConfidence.Strong
                theAlternate.Strokes.ModifyDrawingAttributes(theStrongDA)
            Case RecognitionConfidence.Intermediate
                theAlternate.Strokes.ModifyDrawingAttributes(theIntermediateDA)
            Case RecognitionConfidence.Poor
                theAlternate.Strokes.ModifyDrawingAttributes(thePoorDA)
        End Select
    Next

    ' Redraw the ink.
    Me.theInkCollector.Renderer.Draw(g, Me.theRecognitionResult.Strokes)

    ' Dispose of the graphics object.
    g.Dispose()
End Sub

' Event handler for the form's Closed event.
Private Sub ConfidenceAlternatesForm_Closed(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles MyBase.Closed

    ' Free the resources for the ink collector and recognizer context.
    Me.theInkCollector.Dispose()
    Me.theInkCollector = Nothing
    Me.theRecognizerContext.Dispose()
    Me.theRecognizerContext = Nothing
End Sub

See Also