[wildzzz]

Since the only way to watch most streaming services is through their dedicated player that can already overlay text and graphics, why not just take advantage of that? It would need to be something that can survive video transcoding. Something like very slight dimming and brightening of specific segments of the video could encode an ID. The video would already have a list of random segments identified for encoding and each bit in the ID would tell the player to dim or brighten that segment. If you based the segments off of keyframes, the dimming or brightening might be imperceptible.