VB - Durschnittsfarbe eines Bildes ermitteln

Private Function GetAverageColor(ByVal img As Bitmap, _
                                     Optional ByVal Quality As Integer = 10) As Color
        Dim cDots As New ArrayList
        Dim Red, Blue, Green As Integer
        Dim HoriPoints As Integer = Math.Floor(img.Width / Quality)
        Dim VertiPoints As Integer = Math.Floor(img.Height / Quality)
        Dim result As Color = Color.White
        Try
            For i = 1 To Quality
                Dim x = HoriPoints * i - 1
                For ypos = 1 To Quality
                    Dim y = VertiPoints * ypos - 1
                    cDots.Add(img.GetPixel(x, y))
                Next
            Next
            For Each c As Color In cDots
                Red += c.R
                Blue += c.B
                Green += c.G
            Next
            Dim aColor As Color = Color.FromArgb(Red / cDots.Count, _
                                                 Green / cDots.Count, _
                                                 Blue / cDots.Count)
            result = aColor
        Catch ex As Exception
            Return result
        End Try

        Return result
    End Function