Dim caption As String = "Example: GetCharacterConfidence"
Dim gdpictureOCR As GdPictureOCR = New GdPictureOCR
Dim gdpicturePDF As GdPicturePDF = New GdPicturePDF
'Load the PDF document.
If gdpicturePDF.LoadFromFile("input.pdf", False) = GdPictureStatus.OK Then
    'Select the first page.
    gdpicturePDF.SelectPage(1)
    'Render this page to a 200 DPI image.
    Dim image As Integer = gdpicturePDF.RenderPageToGdPictureImage(200, True)
    If gdpicturePDF.GetStat = GdPictureStatus.OK AndAlso
       gdpictureOCR.SetImage(image) = GdPictureStatus.OK Then
        'Setting up the image is mandatory.
        'Set the New origin for better coordinates handling.
        gdpicturePDF.SetOrigin(PdfOrigin.PdfOriginTopLeft)
        gdpicturePDF.SetLineColor(Color.Orchid)
        gdpicturePDF.SetLineWidth(2)
        'Set up the OCR parameters.
        gdpictureOCR.ResourcesFolder = "C:\Path\To\GdPicture.NET 14\Redist\OCR"
        gdpictureOCR.AddLanguage(OCRLanguage.English)
        gdpictureOCR.OCRMode = OCRMode.FavorAccuracy
        'Set up the OCR context and the character list.
        gdpictureOCR.Context = OCRContext.OCRContextDocument
        gdpictureOCR.CharacterSet = "@"
        'Run the OCR process to recognize the character.
        Dim resID As String = gdpictureOCR.RunOCR()
        If gdpictureOCR.GetStat = GdPictureStatus.OK Then
            Dim charCount As Integer = gdpictureOCR.GetCharacterCount(resID)
            If gdpictureOCR.GetStat() = GdPictureStatus.OK Then
                Dim message As String = "The number of recognized characters: " + charCount.ToString() + vbCrLf
                Dim left As Integer = 0, top As Integer = 0
                For i As Integer = 0 To charCount - 1
                    message = message + "   The confidence of the character nr. " + i.ToString() + " is: " + gdpictureOCR.GetCharacterConfidence(resID, i).ToString()
                    left = gdpictureOCR.GetCharacterLeft(resID, i)
                    top = gdpictureOCR.GetCharacterTop(resID, i)
                    If gdpicturePDF.DrawRectangle(left, top, gdpictureOCR.GetCharacterRight(resID, i) - left, gdpictureOCR.GetCharacterBottom(resID, i) - top, False, True) = GdPictureStatus.OK Then
                        message = message + "   Drawn: yes" + vbCrLf
                    Else
                        message = message + "   Drawn: no" + vbCrLf
                    End If
                Next
                MessageBox.Show(message, caption)
                'Continue with analyzing the result ...
                'Save the page with drawn recognized phone number to the new PDF document.
                If gdpicturePDF.SaveToFile("output.pdf") = GdPictureStatus.OK Then
                    MessageBox.Show("Done!", caption)
                Else
                    MessageBox.Show("The file can't be saved. Status: " + gdpicturePDF.GetStat().ToString(), caption)
                End If
            Else
                MessageBox.Show("The GetCharacterCount() method has failed with the status: " + gdpictureOCR.GetStat().ToString(), caption)
            End If
        Else
            MessageBox.Show("The error occurred when running the OCR. Status: " + gdpictureOCR.GetStat().ToString(), caption)
        End If
        'Release the image.
        GdPictureDocumentUtilities.DisposeImage(image)
    Else
        MessageBox.Show("The error occurred when creating or setting up the image. Status: " + gdpicturePDF.GetStat().ToString() + "/" + gdpictureOCR.GetStat().ToString(), caption)
    End If
    'Close the document.
    gdpicturePDF.CloseDocument()
Else
    MessageBox.Show("The file can't be loaded. Status: " + gdpicturePDF.GetStat().ToString(), caption)
End If
'Release resources.
gdpictureOCR.ReleaseOCRResults()
gdpictureOCR.Dispose()
gdpicturePDF.Dispose()