Script to scale and crop a bunch of wallpapers selected in Finder.app

gistfile1.scpt

tell application "Finder" to set wallpapers to selection

tell application "Image Events"
	repeat with currentWallpaper in wallpapers
		set theWallpaper to open (currentWallpaper as alias)
		tell theWallpaper
			repeat with dim in [{1920, 1080}, {1280, 800}]
				-- Scale and Crop to current dimensions
				scale to size (get item 1 of dim)
				crop to dimensions dim
				
				-- Set up save target
				set namePrefix to text items 1 thru ((offset of "." in (get name)) - 1) of (get name) as string
				tell application "Finder"
					set _ to parent of currentWallpaper as alias
					set parentPath to POSIX path of _
				end tell
				set saveTarget to parentPath & namePrefix & "_" & (get item 1 of dim) & "x" & (get item 2 of dim) & ".jpg"
				
				--save to target
				save in saveTarget as JPEG
			end repeat
		end tell
	end repeat
end tell