compare_images.rb

# Prerequisit: ImageMagick installed

def file_exists?(filename)
  `[ -f #{filename} ] && echo "Found" || echo "Not found"` == "Not found\n"
end

['landing'].each do |screengrab_file_name|
  before = screengrab_file_name + '_before.png'
  after = screengrab_file_name + '_after.png'
  difference = screengrab_file_name + '_difference.png'

  if( file_exists?(before) )
    puts before + " not found"
  elsif( file_exists?(after) )
    puts after + " not found"
  else
    puts `compare -highlight-color yellow -fuzz 3%  #{before} #{after} results/#{difference}`
  end
end