There is a tool called AdBlock that you can download as an addon for your browser. I personally use AdBlock Plus, and I haven't encountered an ad, visible or otherwise, since I installed. This includes those on videos and streams.
Are you talking about Subliminal ads? Those are ads that appear in 2 - 5 frames of film out of usual 24 frames per second. Movie theaters used them *very* briefly in the 70's to flash messages like "Feel Thirsty?" then "Have a soda!!". Your brain registers the message subconsciously but isn't consciously aware of it. In a way, your brain sees the message, but in another it doesn't. That's the closest thing I can think to an "invisible ad" and the government made them illegal in a hurry once they found out theaters were using them. (And by the way, they were VERY effective. When they ran specific ads, "Buy Popcorn before the movie starts", something like 20% of the audience jumped up to go buy popcorn.) Scary, huh? Good thing they're illegal now......... p.s. I've found Ghostery very effective in getting rid of pop-ups, cookies & anything else you don't want tracking or bothering you.. Hope that helps.