Movieclip alignment

hey all i have a product search box on my stage and each product is a different size so i would like to know how to allign to centre once i have halfed the picture size this is how far im upto…

onClipEvent (load) {
myPicture = “pad”;
myPicture._x = myPicture.width/2;
myPicture._y = myPicture.height/2;
setProperty(pad, _x, 0);
setProperty(pad, _y, 98.4);
//myPicture.align?!
}