    #! /usr/local/bin/ruby -w
    require 'RMagick'

    # Demonstrate the Image#normalize method

    before = Magick::Image.read('images/Hot_Air_Balloons.jpg').first
    before = before.scale(250.0/before.rows)

    after = before.normalize

    # Make a before-and-after composite
    after = after.crop(after.columns/2, 0, after.columns/2, after.rows)
    composite = before.composite(after, Magick::EastGravity, Magick::OverCompositeOp)
    composite = composite.border(1,1,'black')

    #composite.display
    composite.write('normalize.jpg')
    exit