i figure out the niche ffmpeg commands various chain filters, etc then expose them from my python cli tool with words similar to what this gentleman above has done.

If one has fewer such commands its as simple as just bash aliases and just adding it to ~/.bashrc

alias convertmkvtomp4='ffmpeg command'

then just run it anytime with just that alias phrase i use ffmpeg a lot so i have my own dedicated cli snippet tool for me, to quickly build out complex pipeline in easier language

the best part is i have --dry-run then exposes the flow + explicit commands being used at each step, if i need details on whats happening and verbose output at each step

I have a text file with some common commands, so no tools needed.

But yea ffmpeg is awesome software, one of the great oss projects imo. working with video is hellish and it makes it possible.