.net 加水印 图片变大很多 解决方法

 /// 给图片加水印 中国红木网 

        /// </summary>

        /// <param name="originalImg"></param>

        /// <param name="waterImg"></param>

        /// <param name="trbl"></param>

        /// <returns></returns>

        public static Image WatermarkImage(Image originalImg, Image waterImg, WatermarkTRBL trbl)

        {

 

            Image image = (Image)originalImg.Clone();

            using (Graphics g = Graphics.FromImage(image))

            {

                Rectangle r = new Rectangle();

                r.Height = waterImg.Height;

                r.Width = waterImg.Width;

                if (trbl.Top != null)

                {

                    r.Y = (int)trbl.Top;

                }

 

                if (trbl.Right != null)

                {

                    r.X = originalImg.Width - waterImg.Width - (int)trbl.Right;

                }

 

                if (trbl.Bottom != null)

                {

                    r.Y = originalImg.Height - waterImg.Height - (int)trbl.Bottom;

                }

 

                if (trbl.Left != null)

                {

                    r.X = (int)trbl.Left;

                }

 

                g.DrawImage(waterImg, r, 0, 0, waterImg.Width, waterImg.Height, GraphicsUnit.Pixel);

            }

 

            return image;

        }

Bitmap b = new Bitmap(image.Width, image.Height,PixelFormat.Format24bppRgb);
Graphics g = Graphics.FromImage(b);

g.Clear(Color.White);
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.Default;
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.Default;
g.DrawImage(image, 0, 0, image.Width, image.Height);

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