Centering a .jpg of a load movie action

Hi, im making a foto gallery, whit different size image’s (portrait and lanscape). This gallery call the images whit a “LadMovie” command an place the images in a target. My problem is that the loadmovie always place the images whit its left-top corner in the white dot of the movie clip. How can i make the images be centralized no matter its size? Can someone help me?