Video BG Replace

Put a talking-head speaker on a new background. The speaker is matted with Robust Video Matting (RVM) on Replicate — a recurrent net with temporal memory, so the matte stays stable frame-to-frame instead of flickering like per-image background removers — then composited over a new background video/image with ffmpeg.

This is the compositing counterpart to broll-generator: that skill generates a silent animated background, this skill marries the matted speaker to it.

The key idea

Both "mask the speaker and drop them on a new bg" and "put an animated video behind the front video" reduce to the same layer stack: