#!/usr/bin/ruby -w require 'RMagick' # Demonstrate the Image#modulate method blonde = Magick::Image.read('images/Blonde_with_dog.jpg').first blonde.scale!(300.0/blonde.rows) after = blonde.modulate(0.85) # Show before and after. after.crop!(after.columns/2, 0, after.columns/2, after.rows) result = blonde.composite(after, Magick::EastGravity, Magick::OverCompositeOp) # Draw a line down the middle. line = Magick::Draw.new line.line(result.columns/2, 0, result.columns/2, result.rows) line.draw(result) #result.display result.write('modulate.jpg') exit