Image pan tutorial, possible to add autopan?

programming flash
1

I am hoping to figure out how to have the panorama image scrolling before the mouseMove in order to attract the viewer attention to it’s interactive qualities. Is that possible with the method below?

this.onMouseMove = function() {
    constrainedMove(bg_mc, 4, 1);
};
function constrainedMove(target:MovieClip, speed:Number, dir:Number) {
    var mousePercent:Number = _xmouse/Stage.width;
    var mSpeed:Number;
    if (dir == 1) {
        mSpeed = 1-mousePercent;
    } else {
        mSpeed = mousePercent;
    }
    target.destX = Math.round(-((target._width-Stage.width)*mSpeed));
    target.onEnterFrame = function() {
        if (target._x == target.destX) {
            delete target.onEnterFrame;
        } else if (target._x>target.destX) {
            target._x -= Math.ceil((target._x-target.destX)*(speed/100));
        } else if (target._x<target.destX) {
            target._x += Math.ceil((target.destX-target._x)*(speed/100));
        }
    };
}