var img = System.Drawing.Image.FromStream(ms);                            int width = img.Width;                            int height = img.Height;                            var x = img.HorizontalResolution;                            var y = img.VerticalResolution;                            var tempHeight = height * 300 / y;                            var tempWidth = width * 300 / y;                            Bitmap bmpTemp = new Bitmap((int)tempWidth, (int)tempHeight);                            Graphics g = Graphics.FromImage(bmpTemp);                            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;                            g.Clear(System.Drawing.Color.White);                            g.DrawImage(img, new RectangleF(0, 0, tempWidth, tempHeight), new RectangleF(0, 0, width, height), GraphicsUnit.Pixel);                            g.Save();                            bmpTemp.Save(target, ImageFormat.Png);                            g.Dispose();                            img.Dispose();                            bmpTemp.Dispose();

 

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