gistfile1.rb

def thumbify
  path = File.join(Rails.root, 'tmp', 'broken_art')
  original_image = 'c11c42280223d6a199c0ffe069a2949ef07ff42a.jpg'

  ImageScience.with_image(File.join(path, original_image)) do |image|
    styles = {
      thumb: { width: 75, height: 75, thumbnail: true, async: true },
      small: { width: 150, height: 150, thumbnail: true, async: true },
      medium: { width: 320, height: 320, thumbnail: true, async: true },
      large: { width: 640, height: 640, thumbnail: true }
    }

    styles.each do |name, vals|
      image.thumbnail(vals[:width]) do |thumb|
        thumb.save(File.join(path, "#{original_image.sub(/\./, "_#{name}.")}"))
      end
    end
  end
end