According to the Beijing Times, 55 seconds of the televised Olympics 2008 firework display? Completely fake:
I was here thinking that like how we all know that china is one of the world’s top manufacturers of gadgets that many gadgets would be used in the everyday task in Beijing and then i came up on this article over by Boing Boing.

The fakery was unearthed by a local Chinese newspaper, The Beijing Times, which revealed that a 55-second sequence was created by a visual effects team, which included a series of giant footsteps made by fireworks.