#!/usr/bin/ruby -w require 'RMagick' # Demonstrate the Image#level method before = Magick::Image.read('images/Jean_Jacket.jpg').first before.scale!(250.0/before.rows) # Allow the white-point argument to default. # This is really a very small adjustment. after = before.level(0,1.25) # Make a before-and-after composite after.crop!(after.columns/2, 0, after.columns/2, after.rows) result = before.composite(after, Magick::EastGravity, Magick::OverCompositeOp) # Draw a black line between the before and after parts. line = Magick::Draw.new line.line(result.columns/2, 0, result.columns/2, result.rows) line.draw(result) #result.display result.write('level.jpg') exit