生成验证码

  1 #!/usr/bin/env python
  2 # -*- coding:utf-8 -*-
  3 
  4 import random
  5 from PIL import Image, ImageDraw, ImageFont, ImageFilter
  6 
  7 _letter_cases = "abcdefghjkmnpqrstuvwxy"  # 小写字母,去除可能干扰的i,l,o,z
  8 _upper_cases = _letter_cases.upper()  # 大写字母
  9 _numbers = ''.join(map(str, range(3, 10)))  # 数字
 10 init_chars = ''.join((_letter_cases, _upper_cases, _numbers))
 11 
 12 
 13 def create_validate_code(
 14         size=(120, 30),
 15         chars=init_chars,
 16         img_type="GIF",
 17         mode="RGB",
 18         bg_color=(255, 255, 255),
 19         fg_color=(0, 0, 255),
 20         font_size=18,
 21         font_type="utils/Monaco.ttf",
 22         length=4,
 23         draw_lines=True,
 24         n_line=(1, 2),
 25         draw_points=True,
 26         point_chance=2
 27 ):
 28     """
 29     @todo: 生成验证码图片
 30     @param size: 图片的大小,格式(宽,高),默认为(120, 30)
 31     @param chars: 允许的字符集合,格式字符串
 32     @param img_type: 图片保存的格式,默认为GIF,可选的为GIF,JPEG,TIFF,PNG
 33     @param mode: 图片模式,默认为RGB
 34     @param bg_color: 背景颜色,默认为白色
 35     @param fg_color: 前景色,验证码字符颜色,默认为蓝色#0000FF
 36     @param font_size: 验证码字体大小
 37     @param font_type: 验证码字体,默认为 ae_AlArabiya.ttf
 38     @param length: 验证码字符个数
 39     @param draw_lines: 是否划干扰线
 40     @param n_lines: 干扰线的条数范围,格式元组,默认为(1, 2),只有draw_lines为True时有效
 41     @param draw_points: 是否画干扰点
 42     @param point_chance: 干扰点出现的概率,大小范围[0, 100]
 43     @return: [0]: PIL Image实例
 44     @return: [1]: 验证码图片中的字符串
 45     """
 46 
 47     width, height = size  # 宽高
 48 
 49     # 创建图形
 50     img = Image.new(mode, size, bg_color)
 51     # 创建画笔
 52     draw = ImageDraw.Draw(img)
 53 
 54     def get_chars():
 55         """生成给定长度的字符串,返回列表格式"""
 56         return random.sample(chars, length)
 57 
 58     def create_lines():
 59         """绘制干扰线"""
 60         line_num = random.randint(*n_line)  # 干扰线条数
 61 
 62         for i in range(line_num):
 63             # 起始点
 64             begin = (random.randint(0, size[0]), random.randint(0, size[1]))
 65             # 结束点
 66             end = (random.randint(0, size[0]), random.randint(0, size[1]))
 67             draw.line([begin, end], fill=(0, 0, 0))
 68 
 69     def create_points():
 70         """绘制干扰点"""
 71         chance = min(100, max(0, int(point_chance)))  # 大小限制在[0, 100]
 72 
 73         for w in range(width):
 74             for h in range(height):
 75                 tmp = random.randint(0, 100)
 76                 if tmp > 100 - chance:
 77                     draw.point((w, h), fill=(0, 0, 0))
 78 
 79     def create_strs():
 80         """绘制验证码字符"""
 81         c_chars = get_chars()
 82         strs = ' %s ' % ' '.join(c_chars)  # 每个字符前后以空格隔开
 83 
 84         font = ImageFont.truetype(font_type, font_size)
 85         font_width, font_height = font.getsize(strs)
 86 
 87         draw.text(((width - font_width) / 3, (height - font_height) / 3),
 88                   strs, font=font, fill=fg_color)
 89 
 90         return ''.join(c_chars)
 91 
 92     if draw_lines:
 93         create_lines()
 94     if draw_points:
 95         create_points()
 96     strs = create_strs()
 97 
 98     # 图形扭曲参数
 99     params = [1 - float(random.randint(1, 2)) / 100,
100               0,
101               0,
102               0,
103               1 - float(random.randint(1, 10)) / 100,
104               float(random.randint(1, 2)) / 500,
105               0.001,
106               float(random.randint(1, 2)) / 500
107               ]
108     img = img.transform(size, Image.PERSPECTIVE, params)  # 创建扭曲
109 
110     img = img.filter(ImageFilter.EDGE_ENHANCE_MORE)  # 滤镜,边界加强(阈值更大)
111 
112     return img, strs

 

posted @ 2018-11-13 08:37  李小样  阅读(77)  评论(0)    收藏  举报