Resizes images so that the shortest side is 250px. Wrote this before the bash version but Finder crashed with the volume of images that had to be processed.

image-resizer.scpt

with timeout of (30 * 60) seconds
	
	tell application "Finder"
		set input_images to every document file of folder "Users:tzayad:Pictures:test" of startup disk whose name extension is "jpg" or name extension is "png"
	end tell
	
	tell application "Image Events"
		launch
		repeat with a from 1 to length of input_images
			try
				set img to open file ((item a of input_images) as string)
				copy dimensions of img to {W, H}
				if W is less than H then
					set scale_l to ((H * 250) / W) + 1
					set scale_l to round scale_l rounding as taught in school
				else
					set scale_l to ((W * 250) / H) + 1
					set scale_l to round scale_l rounding as taught in school
				end if
				scale img to size scale_l
				save img with icon
				close img
			on error errMsg
				-- do nothing
			end try
		end repeat
	end tell
	
end timeout