How difficult would it be to add in a feature where you could feed the program say video.mp4, and have it censor it frame by frame, then pump out a video_censored.mp4 version? You already have ffmpeg as part of the program so I assume splitting audio, censoring and recombining could all be handled with that. At the moment I do something similar with ffmpeg but it applies one kind of blurring, to the whole video rather than specific filters to detected parts.

Or even if it had to be a totally separate program, I would happily pay like £50 for a video processing tool that could censor input videos just like this live tool does and then save them out as a new file. I have been looking for a tool that can detect and censor videos for years with no luck, it's either the whole video gets censored or it's only a live/browser censor. 

I will try to add the possibility to use a video as input for the censoring.

If you don't know, you can already create a recordable window then record it with OBS while watching your video. + with that way, you can see in real time if the effects are working well.

Yea I couldn't get the recordable window to work, it was just black in OBS sadly.
The reason I ask for video processing is that it can run in the background when doing other stuff on the pc or when away from the PC, without having to use up a monitor in the process etc.