.net c# gif动画如何添加图片水印实现思路及代码

public static Bitmap WaterMarkWithText(System.Drawing.Bitmap origialGif, string
text,string filePath)
{
//用于存放桢
List<Frame> frames = new
List<Frame>();
//如果不是gif文件,直接返回原图像
if (origialGif.RawFormat.Guid
!= System.Drawing.Imaging.ImageFormat.Gif.Guid)
{
return origialGif;

}
//如果该图像是gif文件
foreach (Guid guid in
origialGif.FrameDimensionsList)
{
System.Drawing.Imaging.FrameDimension
frameDimension = new System.Drawing.Imaging.FrameDimension(guid);
int
frameCount = origialGif.GetFrameCount(frameDimension);
for (int i = 0; i
< frameCount; i++)
{
if (origialGif.SelectActiveFrame(frameDimension,
i) == 0)
{
int delay =
Convert.ToInt32(origialGif.GetPropertyItem(20736).Value.GetValue(i));
Image
img = Image.FromHbitmap(origialGif.GetHbitmap());
Font font = new Font(new
FontFamily("宋体"), 35.0f,FontStyle.Bold);
Graphics g =
Graphics.FromImage(img);
g.DrawString(text, font, Brushes.BlanchedAlmond,
new PointF(10.0f, 10.0f));
Frame frame = new Frame(img, delay);

frames.Add(frame);
}
}
Gif.Components.AnimatedGifEncoder gif =
new Gif.Components.AnimatedGifEncoder();
gif.Start(filePath);

gif.SetDelay(100);
gif.SetRepeat(0);
for (int i = 0; i <
frames.Count; i++)
{
gif.AddFrame(frames[i].Image);
}

gif.Finish();
try
{
Bitmap gifImg =
(Bitmap)Bitmap.FromFile(filePath);
return gifImg;
}
catch
{

return origialGif;
}
}
return origialGif;
}