code
MagickNET.UseOpenCL = false;
using (MagickImage image = new MagickImage(@"c:\1.jpg"))
{
image.GifDisposeMethod=GifDisposeMethod.Undefined;
image.CompressionMethod=CompressionMethod.LZW;
image.Format = MagickFormat.Gif;
image.Write(@"c:\11.Gif");
//I tried MagickImageCollection, it's no use.
//using (MagickImageCollection col =new MagickImageCollection(image.ToByteArray()))
//{
// col.Coalesce();
// col.Optimize();
// col.OptimizeTransparency();
// col.Write(@"c:\00.Gif");
//}
}
The first one is jpgThe second one is gif
Image may be NSFW.
Clik here to view.

Image may be NSFW.
Clik here to view.
