Alignment options in movie clip loaders?

I was wondering if there was a way to align images(jpegs) loaded into movie clip loaders.The jpegs loaded into a movie clip always align their top left corner with the registration bullseye mark of the movie clip. This forces me to always make the pics the same dimensions even if one picture is vertical format and one is horizontal format. This creates a time consuming extra step in the process. Is there coding available to force the pic to load, lets say, centered into the movie clip so that every pic doesnt haveto be altered/embellished in this way? It looks unprofessional when a vertical format pic loads into the left side of the stage. I hope I’m explaining myself. Hmm. I’d really appreciate your help! Thanks in advance.