About covering an existing watermark
This tool can cover a burned-in watermark (like a NotebookLM mark) by placing your own opaque logo on top of it, or crop it out of frame entirely if it sits near an edge. It can't erase the mark and reconstruct what was underneath — that's video inpainting, a different and much harder problem this tool doesn't attempt. For a corner watermark, cropping usually gives the cleanest result; for a centered one, an opaque logo placed over it works best.