DiffRB = Math.Max(CInt(col.R) - CInt(col.B), 0)
        DiffGB = Math.Max(CInt(col.G) - CInt(col.B), 0)
        If DiffGB = 0 Then
            DiffQuot = 9999
        Else
            DiffQuot = Math.Round(DiffRB / DiffGB, 2)
        End If
        If DiffQuot >= minDQ And DiffQuot <= maxDQ And col.B < MaxB Then
            IstBoden = True
        Else
            IstBoden = False