zoom image effect?

[Nicolas Cueto]

Hello List,

I'm not sure if the zoom-like visual effect I'm after 
is easily done but, here goes.

Basically, when a user enters an image with the mouse, 
that  image will get larger, preferably gradually rather 
than instantly. And once the user exits the image, it'll
return to its original size (again gradually).

Also if possible, when an image object happens to be 
near the edge of the stack, the zoom effect will be
cotained within the stack's edges.

Of course, the resizing could be done by readjusting the
width and height, and the "gradual" effect  with a repeat
loop. But I've no idea how to script the "within stack 
boundaries" limitation. 

(I guess I'm also hoping in part that there already exists a
built-in command in Rev for this effect.)

As always, thank you in advance.

--
Nicolas Cueto