cropping with quicktime

I´m trying to make a droplet that should crop the videos, change size and export it using sorenson video 3.

As I have understood I need to use a mask and then export the videotrack (no sound used) into another file, then export it. Then I will save som data, like filename and weight to a sql-file, but first thing first,

Has anyone done anything like this? :shock:

This is where I get the problem:

on open these_items
set the target_folder to choose folder with prompt “Välj destinationsmapp för kopia:”
repeat with i from 1 to the count of these_items
set this_item to (item i of these_items)
set the item_info to info for this_item
with timeout of 3600 seconds – one hour per movie time limit
tell application “QuickTime Player”

			stop every movie
			close every movie saving no
				open this_item
				set this_file to the original file of movie 1
				set mask of track "Video Track" of movie this_item to file "Machintosh HD:Users:pontusuggla:Desktop:QT-test:mask.jpg"

how did this cropping expirement work out?