vb.net：DPFP.Error.SDKException：验证失败

Question

我在使用vb.net 2010进行指纹验证时遇到问题。我不确定每次从mysql数据库验证模板时是什么造成错误。以下是错误消息。我使用数字人物u.are.u 4000b作为我的指纹扫描仪。

这是我的验证码：

 DrawPicture(ConvertSampleToBitmap(Sample))

    Dim features As DPFP.FeatureSet = ExtractFeatures(Sample, DPFP.Processing.DataPurpose.Verification)

    conn.Open()
    cmd.Connection = conn
    cmd.CommandText = "Select * from emp_t"
    dr = cmd.ExecuteReader

    If dr.HasRows Then
        While dr.Read()

            Dim MemStream As IO.MemoryStream
            Dim fpBytes As Byte()

            fpBytes = dr(2)
            MemStream = New IO.MemoryStream(fpBytes)

            Dim templa8 As DPFP.Template = New DPFP.Template()
            templa8.DeSerialize(MemStream)

            Me.Template = templa8

            ' Check quality of the sample and start verification if it's good
            If Not features Is Nothing Then
                ' Compare the feature set with our template
                Dim result As DPFP.Verification.Verification.Result = New DPFP.Verification.Verification.Result()
                Try
                    Verificator.Verify(features, templa8, result)
                Catch ex As Exception
                    MsgBox(ex.ToString)
                End Try
                If result.Verified Then
                    MessageBox.Show("Verified")
                    Exit Sub
                Else
                    MessageBox.Show("The fingerprint was NOT VERIFIED!")
                End If
            Else
                MessageBox.Show("Fingerprint sample is not established!")
            End If


        End While
    Else
        MessageBox.Show("No record found!")
    End If

    conn.Close()

我一直在努力寻找解决问题的方法。任何能够分享想法和扩展帮助的人都会非常感激......谢谢...