For using the filter all you have to do is download the repo and the libraries. After that just run the code, when the window is opened, open your hand wide open and than you'll see the magic circles.
I have used mediapipe's hand detection features for placing and sizing magic circles correctly.
For iamges i created a function for replacing blacks pixels with background image.
If you want to add new magic circle styles all you have to do is create a png img with black background. After that you are good to go. (you can examine images i used)