There probably is, provided you can get a perceptual model that correctly models all human visual perception and reduce it to a hash. I am not sure one exists currently. Until then, it really does seem like we're trying to find a way to re-implement trademarks in a way that doesn't require the interpretive work that trademarks rely on.
I suspect there's a lot of complexity hidden in the perceptual model requirement, though.
I suspect there's a lot of complexity hidden in the perceptual model requirement, though.