How does this illuminated Beijing advertising technology work?
May 15, 2012 8:35 AM Subscribe
How does this advertising wizardry in the Beijing subway work?
posted by stonepharisee to Technology (10 answers total) 2 users marked this as a favorite
In Beijing, while a subway train is in a tunnel, illuminated ads often appear, in what looks like a long row of identical projections. The train is moving. Each projection/frame shows a constant, sometimes moving, picture. The entire picture sequence is only approximately synchronized with the forward rate of the train. Then they abruptly disappear. The only people I have asked about it shrug, as they see no interest in the ads. To me it is technological wizardry of the highest order. I can't imagine what the technology is that allows it. Multiple projectors on rails overhead moving back and forward sound highly implausible.
Anyone know if I am missing the screamingly obvious here, or better yet, know the wizardry involved?