Zoom with mouse (over) on image

Hi,

I have an image 600x50 and I would like to zoom in on rollover.
When i rollover on the image its zooming in but from the center of the picture.
I would like to also be able to zoom when I mouse the mouse to the left or to the right so I zoom on specific areas.

How do I do that ?Can someone help me?

Thank you,

Melissa Anne