In VB.net Bilder verändern (Auflösung, RGB, CYMK...)

Dim OldImage1 As New Bitmap("c:\Beispiel QuellBildDatei.jpg")  
Dim NewWidth1 As Integer = 300
Dim NewHeight1 As Integer = 300
Dim NewImage1 As New Bitmap(NewWidth1, NewHeight1, System.Drawing.Imaging.PixelFormat.Format24bppRgb)

            Using G As Graphics = Graphics.FromImage(NewImage1)
                G.InterpolationMode = Drawing2D.InterpolationMode.HighQualityBicubic
                G.PixelOffsetMode = Drawing2D.PixelOffsetMode.HighQuality
                G.CompositingQuality = Drawing2D.CompositingQuality.HighQuality
                G.SmoothingMode = Drawing2D.SmoothingMode.HighQuality
                G.DrawImage(OldImage1, New System.Drawing.Rectangle(0, 0, NewWidth1, NewHeight1))
            End Using

NewImage1.Save("c:\Beispiel ZielBildDatei.jpg", System.Drawing.Imaging.ImageFormat.Jpeg)