代码：

# -*- coding: UTF-8 -*-from __future__ import unicode_literalsimport cStringIOimport loggingimport randomfrom PIL import Image, ImageDraw, ImageFontfrom django.utils import cryptologger = logging.getLogger('django')class VerificationCode(object):    """    验证码类    """    __r_g_b_list = [(200, 0, 0), (0, 200, 0), (0, 0, 200), (0, 200, 200), (200, 0, 200), (200, 200, 0),                    (235, 75, 75), (211, 44, 230), (136, 71, 255), (75, 105, 255), (94, 152, 217), (228, 174, 57),                    (106, 90, 205), (123, 104, 238), (65, 105, 225), (100, 149, 237), (70, 130, 180), (95, 158, 160),                    (102, 139, 139), (104, 131, 139), (100, 149, 237), (92, 172, 238), (205, 133, 63), (205, 133, 0)]    def __init__(self, font_dir):        """        验证码类        :param font_dir:        """        self.image_mode = 'RGB'        self.width = 90        self.height = 35        self.image_color = (220, 220, 220)        self.font_size = 20        self.font_list = self.__get_font_list(font_dir)        self.ink_list = VerificationCode.__get_ink_list()    def get_v_code_image_png(self):        """        生成验证码图像数据和验证码字符串        :return:        """        v_code_str = crypto.get_random_string(length=4)        _image = Image.new(self.image_mode, [self.width, self.height], self.image_color)        draw = ImageDraw.Draw(_image)        left_margin = -16        for i, _char in enumerate(v_code_str):            left_margin += 20            top_margin = random.randrange(2, 16)            draw.font = self.__get_random_font()            draw.ink = self.__get_random_ink()            if random.randint(0, 1):                _char = _char.upper()            draw.text([left_margin, top_margin], _char)        if random.randint(0, 1):            x1, y1, x2, y2 = self.__get_random_line()            draw.line((x1, y1, x2, y2), 'MediumPurple')        if random.randint(0, 1):            x1, y1, x2, y2 = self.__get_random_line()            draw.line((x1, y1, x2, y2), 'Thistle')        if random.randint(0, 1):            x1, y1, x2, y2 = self.__get_random_line()            draw.line((x1, y1, x2, y2), 'Peru')        del draw        v_code_buf = cStringIO.StringIO()        _image.save(v_code_buf, 'png')        return v_code_buf, v_code_str    def __get_random_font(self):        """        随机字体        :return:        """        if self.font_list:            font = random.choice(self.font_list)        else:            font = ImageFont.load_default()        return font    def __get_random_ink(self):        """        随机ink        :return:        """        if self.ink_list:            ink = random.choice(self.ink_list)        else:            ink = 100 + 100 * 256 + 100 * 256 * 256        return ink    def __get_random_line(self):        """        随机干扰线端点坐标        :return:        """        x1 = random.randrange(int(self.width*.1), int(self.width*.9))        y1 = random.randrange(int(self.height*.1), int(self.height*.9))        x2 = random.randrange(int(self.width*-.6), int(self.width*.6)) + x1        y2 = random.randrange(-5, 5) + y1        return x1, y1, x2, y2    def __get_font_list(self, font_dir):        """        :param font_dir:        :return:        """        # font file list        file_list = [font_dir + '/FreeMono.ttf',                     font_dir + '/FreeMonoBold.ttf',                     font_dir + '/FreeMonoBoldOblique.ttf',                     font_dir + '/FreeMonoOblique.ttf',                     font_dir + '/FreeSans.ttf',                     font_dir + '/FreeSansBold.ttf',                     font_dir + '/FreeSansBoldOblique.ttf',                     font_dir + '/FreeSansOblique.ttf',                     font_dir + '/FreeSerif.ttf',                     font_dir + '/FreeSerifBold.ttf',                     font_dir + '/FreeSerifBoldItalic.ttf',                     font_dir + '/FreeSerifItalic.ttf']        font_list = list()        for _file in file_list:            try:                font = ImageFont.truetype(_file, self.font_size)                font_list.append(font)            except BaseException as e:                logger.error('get_font_list:%s' % e)        return font_list    @staticmethod    def __get_ink_list():        """        :return:        """        ink_list = []        for r, g, b in VerificationCode.__r_g_b_list:            ink = r + g * 256 + b * 256 * 256            ink_list.append(ink)        return ink_list

使用：

v_code_obj = VerificationCode(settings.GNU_DIR)def verification_code(request):    """    生成验证码    :param request:    :return:    """    v_code_buffer, v_code_str = v_code_obj.get_v_code_image_png()    request.session['v_code'] = v_code_str.lower()    return HttpResponse(v_code_buffer.getvalue(), 'image/png')

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