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

    # Demonstrate the Image#cycle_colormap method

    balloons = Magick::Image.read('images/Hot_Air_Balloons.jpg').first
    balloons = balloons.scale(250.0/balloons.rows)
    balloons = balloons.quantize(256, Magick::RGBColorspace)

    jump = balloons.colors / 10

    animation = Magick::ImageList.new
    animation[0] = balloons

    5.times { animation << animation.cycle_colormap(jump) }
    4.times { animation << animation.cycle_colormap(-jump) }

    animation.delay=20
    animation.iterations = 10000
    #animation.animate
    animation.write('cycle_colormap.gif')
    exit