How to make ripple effect

Can anyone explain how to do the liquid/ripple effect on menu buttons like on http://www.derbauer.de/ ??

maybe just a clever keyframe animation??? looks like it was created in something like photoshop and just keyframed…

i might be wrong.

It could be, but does that mean that they created, say, 15 pics, each a little different, then loaded them in each successive frame?

I have the buttons and interface created in Photoshop, but am wondering if this is a shape tween or something along that line.

Anyhoo, thanks for the reply, guess I will have to keep digging.

yea, its probably done using a sequence of images. A shape tween wouldn’t be able to do that.