Cambiar tamaño de imágenes

string serverPath = Server.MapPath(string.Format("~/{0}/tipoalojamiento_{1}.jpg", Properties.Resources.PathUpload, imagen.ImagenTipoAlojamientoDTO.Id));
if (System.IO.File.Exists(serverPath)) System.IO.File.Delete(serverPath);
System.Drawing.Image image = System.Drawing.Image.FromStream(file.InputStream);
widthImg = int.Parse(Properties.Resources.WidthImg);
heightImg = int.Parse(Properties.Resources.HeightImg);
Bitmap bmp = new Bitmap(image, new Size(widthImg,heightImg));
bmp.Save(serverPath);
bmp.Dispose();
image.Dispose();
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