They're in japanese. He's japanese. The japanese characters are actually representing the sound the beats are making. Basically Japanese characters have a specific "letter" for something that sounds like "Pow", and it's different from a "soft pow", and so on and so forth, while the english language only has POW!!! and pow...
Which is why the video is incredibly clever. He's visualized the sound he was making.
Try this one too:
Same guy... I'm listening to everything he's got that I can find. Apparently his CD is a Japan-only release.