Ruby RMagick 验证码生成

http://babo.javaeye.com/blog/72298

class Captcha

  require 'rubygems'
  require 'RMagick'
#  rmagick_test.rb:4:in `require': no such file to load -- RMagick (LoadError) ，上面那个require 'rubygems' 如果不放有时会报这个错误。

  include Magick

  attr_reader :code, :code_image  #类的2个属性

  def initialize(len)

    #chars = ('a'..'z').to_a-['a','e','i','o','u']

    code_array=[]

    codex=""

    rr=0

    1.upto(5) {

      rr=65+rand(25)

      code_array << rr

    }            #随机生成5个大写字母

    #code_array=[rand(rr).chr,rand(rr).chr,rand(rr).chr,rand(rr).chr]

    #1.upto(len) {code_array << chars[rand(chars.length)]}

    granite = Magick::ImageList.new('granite:')    #生成granite样式的背景

    canvas = Magick::ImageList.new    #定义一个画布

    canvas.new_image(24*4,20, Magick::TextureFill.new(granite))   #granite放画布上

    text = Magick::Draw.new    #文字

    #text.font_family = 'times'

    text.pointsize = 20                  #文字大小

    cur = 10

    code_array.each{|c|

      c=c.to_i

      c=c.chr

      codex=codex+c               #acs码（数字）转为字母

      #rand(10) > 5 ? rot=rand(Wobble):rot= -rand(Wobble)

      rand(10) > 5 ? weight = NormalWeight : weight = BoldWeight

      ra=1000

      while ra<100000

        ra=rand(999999)

      end

      rn='#'+ra.to_s

      text.annotate(canvas,20,20, cur,18,c){      #text对象放canvas上

        self.rotation=rand(30)                     #旋转角度

        self.font_weight = weight



        self.fill = rn                              #text（文字）颜色

      }

      cur += 15

    }

    @code = codex                                #生成文字（字符串格式）


    @code_image = canvas.to_blob{              #生成图片(二进制格式)

      self.format="JPG"

    }

  end
end
img = Captcha.new(4)
File.open('img.jpg','wb+') do |f|
  f << img.code_image
end