# level_colors.rb

    require 'RMagick'

    img = Magick::Image.read("images/Flower_Hat.jpg").first
    begin
      img = img.level_colors("green", "orange", true)
      img.alpha(Magick::DeactivateAlphaChannel)
    rescue NotImplementedError
      not_imp = Magick::Image.read('images/notimplemented.gif').first
      img = not_imp.resize(img.columns, img.rows)
    end
    img.write("level_colors.jpg")

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