Mask that pans image on x scale

Hey, I’m trying to get an effect, where I have an image bigger than the stage, and I want to drag to the left, and have the right move off to the right, away from the viewpoint. and vice versa. Only for the x scale though, not the y.
So, the users viewpoint would drag left when they rolled there mouse to the left, and would drag right when they moved there mouse to the right.
I’m guessing it involves invisible buttons, placed on the left and the right, that would have on(rollover) commands.

Heres an image, for those visually inclined.

Any help would be great,
Murv