Change image size in asp.net with C#.

System.Drawing.Image image = System.Drawing.Image.FromFile(url+"/"+filename);

            int srcWidth = image.Width;

            int thumbWidth;

            int srcHeight = image.Height;

            int thumbHeight = 440;

            Bitmap bmp = new Bitmap(thumbWidth, thumbHeight);

            System.Drawing.Graphics gr = System.Drawing.Graphics.FromImage(bmp);

            gr.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

            gr.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;

            gr.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

            System.Drawing.Rectangle rectDestination = new 

            System.Drawing.Rectangle(0, 0, thumbWidth,  thumbHeight);

            gr.DrawImage(image, rectDestination, 0, 0, srcWidth, srcHeight, GraphicsUnit.Pixel);

            string newfilename = filename.Substring(0, filename.LastIndexOf('.'))+reference;

            string fileExt=filename.Substring(filename.LastIndexOf('.'));

            bmp.Save(url + "\\" + newfilename + fileExt);

            bmp.Dispose();           

            image.Dispose();