Using gr As Graphics = Graphics.FromImage(Bild.Image)
            Dim si As Size = TextRenderer.MeasureText(gr, s, fo, New Size, _
              TextFormatFlags.NoPadding)
            TextRenderer.DrawText(gr, s, fo, New Point(0, 0), Color.Black, _
            Color.White, TextFormatFlags.NoPadding)
            'gr.DrawString(s, fo, Brushes.Black, New Point(0, 0)) nicht 
            ' benutzen!
            gr.DrawRectangle(Pens.Red, New Rectangle(0, 0, si.Width, si.Height))
        End Using

Dont debug, because there will allways be one more bug