验证码程序

验证码图片

# in app/models/ 
class NoisyImage  
   require 'RMagick'  
   include Magick  
   
   attr_reader :code, :code_image  
   
   def initialize(length = 4)  
     text_size = 20
     validbglinecolors = ['#FFF', '#FFF', '#FFF', '#FFF', '#FFF']
     validchars = (0..9).to_a  
     step = -20   
     chars = []  
     text_size_step = text_size * 0.7
     length.times {|x|  
         chars << validchars[rand(validchars.size).ceil - 1].to_s  
     } 
      
     bglinecolor = validbglinecolors[1]  
     image = Image.new(length * text_size_step + 0, 24, HatchFill.new('white', bglinecolor, 1))
    text = Draw.new  
     #使用字体文件和直接使用字体，或者不写font, font_family两个属性都是如图所示结果，linux下无字显示  
     #text.font = "fonts/arial.ttf"# + #['times.ttf', 'arial.ttf', 'verdana.ttf', 'artro.ttf'].sort{rand}.pop
     #text.font_family = ['times', 'sans', 'fixed', 'Verdana'].sort{rand}.pop  
     text.font_weight = BoldWeight  
     text.text(0,0, ' ')  
   
     chars.each {|char|  
         text.annotate(image,0 , 0, step,  3, char) {
             self.rotation = 5#dist[rand(dist.size - 1).ceil]
             self.fill = "#000"#colors[rand(colors.size - 1).ceil]
             self.pointsize = 22
         }  
         step += text_size_step - rand(5)  
     }  
     text.draw(image)  
 
     @code = chars.to_s()
     @code_image = image.to_blob{ self.format="JPG" }  
   end  
 end