Zoom into Image help

Hey guys,
I’m looking for a way to zoom into an image, but controlled by the _ymouse. Also the center of the image is 100% zoomed in and it will zoom out at the edges…

This is like the OSx dock menu effect, but controlled by the vertical, and the center of the image being the “zoomed” in…

I’m trying something like:
_root.mymc._xscale += this._ymouse / mymc._height;

same thing for the yscale, this does the opposite, zooms out at the edges and stops at the center… I understand my ymouse is dividing the height and the center is “0” so no zoom, above that it zooms out, below the opposite…

How can I achieve what I want, I’m trying to have a panoramic image and when you scroll your mouse by the center it zooms in and as you move away from the center, it zooms out…

Any help is appreciated!!