#!/usr/bin/ruby -w require 'RMagick' # Demonstrate the Image#threshold method jj = Magick::Image.read('images/Jean_Jacket.jpg').first jj.scale!(250.0/jj.rows) # Use a threshold of 40% of MaxRGB. jj = jj.threshold(Magick::MaxRGB*0.40) #jj.display jj.write('threshold.jpg') exit