Imagemagic append images vertically or horizontally.

mini_magic_append_images.rb

# http://www.imagemagick.org/script/command-line-options.php#append
# append two images vertically
# conver -append first.png second.png result.png
MiniMagick::Tool::Convert.new do |convert|
  convert.append.-
  convert << "first.png"
  convert << "second.png"

  convert << "result.png"
end

# append two images horizontally
# conver +append first.png second.png result.png
MiniMagick::Tool::Convert.new do |convert|
  convert.append.+
  convert << "first.png"
  convert << "second.png"

  convert << "result.png"
end