I periodically have to process one or another video. And also there is a need to replace faces in the frame. How to do this manipulation better?

I think you can try to use Photoshop or there are not a few other programs that would change the faces in the video. Author, in your case, I would recommend to study the topic at https://wishapp.ai/ There everything is detailed on how to do face swapping video for free. I am sure you will find this topic useful.

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