昨天的實現，效率非常低，基本要10s左右，今天重新改良了一下gif的Encoder,效率提高了不，基本實現了gif添加水印，但透明的gif在添加水印的時候仍然存在問題，有時間再研究研究
原gif

水印之后的圖片為:

但是，透明背景的卻有些問題
原圖

水印后

改動的部分

 1  protected void GetImagePixels()
 2        {
 3            int w = image.Width;
 4            int h = image.Height;
 5            //        int type = image.GetType().;
 6            if ((w != width)
 7                || (h != height)
 8                )
 9            {
10                // create new image with right size/format
11                Image temp =
12                    new Bitmap(width, height);
13                Graphics g = Graphics.FromImage(temp);
14                g.DrawImage(image, 0, 0);
15                image = temp;
16                g.Dispose();
17            }
18            /**//*
19                ToDo:
20                improve performance: use unsafe code 
21            */
22            pixels = new Byte[3 * image.Width * image.Height];
23            int count = 0;
24            Bitmap tempBitmap = new Bitmap(image);
25            int wh = image.Width;
26            int he = image.Height;
27            System.Drawing.Imaging.BitmapData bmpData = tempBitmap.LockBits(new Rectangle(0, 0, wh, he), System.Drawing.Imaging.ImageLockMode.ReadWrite, image.PixelFormat);
28            unsafe
29            {
30                byte* p = (byte*)bmpData.Scan0.ToPointer();
31                for (int i = 0; i < 4 * wh * he; i += 4)
32                {
33                    pixels[count] = *(p + i+2);
34                    count++;
35                    pixels[count] = *(p + i + 1);
36                    count++;
37                    pixels[count] = *(p + i );
38                    count++;
39                }
40            }
41            tempBitmap.UnlockBits(bmpData);
42            //count = 0;
43            //for (int th = 0; th < image.Height; th++)
44            //{
45            //    for (int tw = 0; tw < image.Width; tw++)
46            //    {
47            //        Color color = tempBitmap.GetPixel(tw, th);
48            //        pixels[count] = color.R;
49            //        count++;
50            //        pixels[count] = color.G;
51            //        count++;
52            //        pixels[count] = color.B;
53            //        count++;
54            //    }
55            //}
56
57            //        pixels = ((DataBufferByte) image.getRaster().getDataBuffer()).getData();
58        }