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Public Function InvertColors(ByVal Image As Image) As Image
    Dim ImgAttr As New Imaging.ImageAttributes()

    'Default-ColorMatrix for Inverting
    Dim ColorMatrix As New Imaging.ColorMatrix(New Single()() {New Single() {-1, 0, 0, 0, 0}, New Single() {0, -1, 0, 0, 0}, New Single() {0, 0, -1, 0, 0}, New Single() {0, 0, 0, 1, 0}, New Single() {0, 0, 0, 0, 1}})

    'Apply ColorMatrix to Image
    ImgAttr.SetColorMatrix(ColorMatrix)

    'Create new 32bit Bitmap
    Dim NewBitmap = New Bitmap(Image.Width, Image.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb)

    'Set resolution from Sourceimage to Targetimage
    NewBitmap.SetResolution(Image.HorizontalResolution, Image.VerticalResolution)

    'Create Graphicsobject from NewBitmap
    Dim NewGraphics As Graphics = Graphics.FromImage(NewBitmap)

    'Draw NewBitmap on NewGraphics
    NewGraphics.DrawImage(Image, New Rectangle(0, 0, NewBitmap.Width, NewBitmap.Height), 0, 0, Image.Width, Image.Height, GraphicsUnit.Pixel, ImgAttr)

    'Dispose ressources
    NewGraphics.Dispose()
    ImgAttr.Dispose()
    Return NewBitmap
End Function