GIF图片的放大实现

public Image ZoomIn(Image originImg, int newWidth, int newHight)
     {
         int frameCount = originImg.GetFrameCount(new FrameDimension(originImg.FrameDimensionsList[0]));
         if (frameCount > 1)
         {
             string path = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString() + ".gif");
             AnimatedGifEncoder ge = new AnimatedGifEncoder();
             ge.Start(path);
             ge.SetRepeat(0);
             FrameDimension dim = new FrameDimension(originImg.FrameDimensionsList[0]);
             for (int i = 0; i < originImg.GetFrameCount(dim); i++)//遍历图像帧
             {

                 originImg.SelectActiveFrame(dim, i);//激活当前帧
                 int delay = 0;
                 for (int j = 0; j < originImg.PropertyIdList.Length; j++)//遍历帧属性
                 {
                     if ((int)originImg.PropertyIdList.GetValue(j) == 0x5100)//.如果是延迟时间
                     {
                         PropertyItem pItem = (PropertyItem)originImg.PropertyItems.GetValue(j);//获取延迟时间属性
                         byte[] delayByte = new byte[4];//延迟时间，以1/100秒为单位
                         delayByte[0] = pItem.Value[i * 4];
                         delayByte[1] = pItem.Value[1 + i * 4];
                         delayByte[2] = pItem.Value[2 + i * 4];
                         delayByte[3] = pItem.Value[3 + i * 4];
                         delay = BitConverter.ToInt32(delayByte, 0) * 10; //乘以10，获取到毫秒
                         break;
                     }
                 }
                 ge.AddFrame(PicSized((Bitmap)originImg, newWidth, newHight));
                 ge.SetDelay(delay);
             }
             ge.Finish();
             return Image.FromFile(path);

         }
         else
         {
             return PicSized((Bitmap)originImg, newWidth, newHight);
         }
     }

     public Bitmap PicSized(Bitmap originBmp, int newWidth, int newHight)
     {
         Bitmap resizedBmp = new Bitmap(newWidth, newHight);
         Graphics g = Graphics.FromImage(resizedBmp);
         g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
         g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
         g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
         g.SmoothingMode = SmoothingMode.AntiAlias;
         g.DrawImage(originBmp, new Rectangle(0, 0, newWidth, newHight), new Rectangle(0, 0, originBmp.Width, originBmp.Height), GraphicsUnit.Pixel);
         g.Dispose();
         return resizedBmp;
     }

使用

 

pbCode.Image = ZoomIn(image, pbCode.Width, pbCode.Height);