python验证码

深碍√TFBOYSˉ_ 2022-04-15 05:53 245阅读 0赞

## 验证码 ##

### 安装Pillow库 ###

PIL：Python Imaging Library，已经是Python平台事实上的图像处理标准库了。PIL功能非常强大，但API却非常简单易用。

由于PIL仅支持到Python 2.7，加上年久失修，于是一群志愿者在PIL的基础上创建了兼容的版本，名字叫[Pillow][]，支持最新Python 3.x，又加入了许多新特性，因此，我们可以直接安装使用Pillow。

$ pip install pillow

### 创建验证码步骤 ###

1)、创建画布  
 2)、生成验证码字符串  
 3)、画验证码  
 4)、画干扰点  
 5)、画干扰线  
 6)、返回验证码图片

### 常用方法 ###

<table> 
 <thead> 
  <tr> 
   <th>方法名</th> 
   <th>说明</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>Image.new()</td> 
   <td>创建图像</td> 
  </tr> 
  <tr> 
   <td>ImageDraw.Draw</td> 
   <td>创建画笔</td> 
  </tr> 
  <tr> 
   <td>ImageDraw.point</td> 
   <td>画点</td> 
  </tr> 
  <tr> 
   <td>ImageDraw.line</td> 
   <td>画线</td> 
  </tr> 
  <tr> 
   <td>ImageDraw.text</td> 
   <td>画文字</td> 
  </tr> 
  <tr> 
   <td>ImageFont.truetype</td> 
   <td>获取字体</td> 
  </tr> 
 </tbody> 
</table>

### 实现 ###

from io import BytesIO
    from random import randint,sample
    import string
    
    from PIL import Image,ImageFont,ImageDraw
    
    class VerifyCode:
        def __init__(self,width=100, height=40,size=4):
            self.width = width
            self.height = height
            self.size = size    #验证码长度
            self.__code = None  #保存验证码字符串
            self.pen = None     #画笔
        @property
        def code(self):  #获取验证码字符串的方法
            return self.__code
    
        def output(self):
            # 1 image pen
            im = Image.new('RGB', (self.width, self.height),self.__rand_color(160,255))
            self.pen = ImageDraw.Draw(im)
    
            # 2code string
            self.__code = self.rand_string()
    
            # 3 draw string
            self.__draw_string()
            # 4 point
            self.__disturb_point()
            # 5 line
            self.__draw_line()
            # 6 return图片的二级制
            # im.save('yzm.png','PNG')  #保存图片
            buf = BytesIO()
            im.save(buf, 'PNG')
            res = buf.getvalue()
            buf.close()
            return res
    
        def __draw_line(self):
            for i in range(5):
                start_point = (randint(1,self.width - 1),randint(1,self.height - 1))
                end_point = (randint(1,self.width - 1),randint(1,self.height - 1))
                self.pen.line([start_point,end_point],fill=self.__rand_color(50,100))
        def __disturb_point(self):
            for i in range(300):
                x = randint(1,self.width - 1)
                y = randint(1,self.height - 1)
                self.pen.point([(x,y)],fill=self.__rand_color(60,120))
    
        def __draw_string(self):
            font1 = ImageFont.truetype('SIMLI.TTF',size=20,encoding='utf-8')
            width = (self.width - 20) / self.size
            for i in range(len(self.__code)):
                x = 13 + i * width
                y = randint(5,20)
                self.pen.text((x, y),self.__code[i],fill='black',font=font1)
    
        def rand_string(self):
            # 数字验证码
            return str(randint(1000,pow(10,self.size)) - 1)
    
        def __rand_color(self,low,high):
            return randint(low,high),randint(low,high),randint(low,high)

### Django的使用 ###

[views.py][]

from VerifyCode import VerifyCode
    def yzm(request):
        image = VerifyCode()
        result = image.output()
        request.session['code'] = image.code
        return HttpResponse(result,'image/png')

[Pillow]: https://pillow.readthedocs.org/
[views.py]: http://views.py