Create a bunch of resized icons for iOS projects

make-ios-icons.rb

#!/usr/bin/ruby

# Takes one large image (say, 512 or 1024 px) and creates some iOS icons:
#
# Icon-72.png
# Icon-Small-50.png
# Icon-Small.png
# Icon-Small@2x.png
# Icon.png
# Icon@2x.png

require 'rubygems'
require 'image_science'

unless ARGV.length == 1
	print "usage: make-ios-icons.rb big-ass-image.png\n"
	exit
end

names = %w{Icon-72.png Icon-72@2x.png Icon-Small-50.png Icon-Small.png Icon-Small@2x.png Icon.png Icon@2x.png}
sizes = [72, 144, 50, 29, 58, 57, 114]

ImageScience.with_image(ARGV[0]) do |img|

	sizes.zip(names).each do |size_name|
		img.resize(size_name[0], size_name[0]) do |img2|
			img2.save size_name[1]
		end
	end

end