I am not sure I understand your question. In the example
online the overlay picture that is the blur has it's alpha set to
0. When a user rolls over the picture the alpha'ed picture slowly
comes into view and then on roll out goes out of view again. Are
you asking how to,
1. Have the picture start blurry?
2 Focus the picture based on a time interval or a mouse
click, any event other that the rollOver?
Or, do you want the image go from blurry to in-focus as an
animation? Then, you'd just do a tween with the alpha of the
overlay, and that can be done on the timeline or with AS.
Actually, if you want this to happen automatically, without
any user interaction, you don't have to use ANY actionscript at
all. Just put the blurry image on a layer above the focused image,
and make a tween to fade out the blurry image as you desire.