Dither Edges of gif. How to make them smooth?

[hafizmabuzar]

I get jaggie edges of gif when I create it from png images. How can I make the edges smooth.
The png images have the smooth edges but the output gif has the dither edges.

Any solution will be highly appreciated.
Here is my code:

using (MagickImageCollection collection = new MagickImageCollection())
{
ImageOperations oImageOperations = new ImageOperations();
int DelayIndex = 10;
for (double k = 1; k <= MaxFrames; k++)
{
string ImgPath = TempDirPath + "/" + ecover_name + "_" + k.ToString() + ".png";

                MagickImage img = new MagickImage(oImageOperations.GetStreamedImage(ImgPath));
                img.AnimationDelay = DelayIndex;
                img.GifDisposeMethod = GifDisposeMethod.Background;
                img.AntiAlias = true;
                img.HasAlpha = true;
                img.VirtualPixelMethod = VirtualPixelMethod.Transparent;
                collection.Add(img);
             
            }

            collection.Optimize();
            collection.Write(ImagePath + "\\" + ecover_name + ".gif");

        }

[dlemstra]

Can you also share your input images?

[hafizmabuzar]

Here they are

[hafizmabuzar]

And the actual output (previously I uploaded the smaller resized version).

[dlemstra]

There is no solution for this. GIF only supports binary transparency. So any antialiasing would be negated by the quantization from 8-bit alpha to binary alpha.

[hafizmabuzar]

It is not possible in Magick.net or it is not achievable in any framework or image library? Can you do me a favor, please recommend any imaging library in which it is possible. Thankyou

[dlemstra]

This not possible due to the limitations of the GIF format. You will either have a transparent or an opaque pixel. Values in between are not possible in GIF and that is what will give you the smooth edges.

[hafizmabuzar]

Quite disappointed to know that. Just do me another favor by sharing the code that can put a thin feather around the edges of gif so that dithered edges may get bit blurry and non-prominent. This must be possible in magick.net. I tried to do it but could not do it. So please help. Thankyou.