validate_code.py

#!/usr/bin/env python
# coding=utf-8
import random
import os
import Image, ImageDraw, ImageFont, ImageFilter

fontType = "/home/jedrek/work_dir/my_project/myflask/FZZCHJW.TTF"


def create_validate_code(size=(120, 30),
                         chars='abcdefghjkmnpqrstuvwxyABCDEFGHJKMNPQRSTUVWXY3456789',
                         img_type="GIF",
                         mode="RGB",
                         bg_color=(255, 255, 255),
                         fg_color=(0, 0, 255),
                         font_size=18,
                         font_type=fontType,
                         length=4,
                         draw_lines=True,
                         n_line=(1, 2),
                         draw_points=True,
                         point_chance=2):
    '''
    @todo: 生成验证码图片
    @param size: 图片的大小，格式（宽，高），默认为(120, 30)
    @param chars: 允许的字符集合，格式字符串
    @param img_type: 图片保存的格式，默认为GIF，可选的为GIF，JPEG，TIFF，PNG
    @param mode: 图片模式，默认为RGB
    @param bg_color: 背景颜色，默认为白色
    @param fg_color: 前景色，验证码字符颜色，默认为蓝色#0000FF
    @param font_size: 验证码字体大小
    @param font_type: 验证码字体，默认为 ae_AlArabiya.ttf
    @param length: 验证码字符个数
    @param draw_lines: 是否划干扰线
    @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
    @param draw_points: 是否画干扰点
    @param point_chance: 干扰点出现的概率，大小范围[0, 100]
    @return: [0]: PIL Image实例
    @return: [1]: 验证码图片中的字符串
    '''

    width, height = size  # 宽， 高
    img = Image.new(mode, size, bg_color)  # 创建图形
    draw = ImageDraw.Draw(img)  # 创建画笔
    if draw_lines:
        create_lines(draw, n_line, width, height)
    if draw_points:
        create_points(draw, point_chance, width, height)
    strs = create_strs(draw, chars, length, font_type, font_size, width, height, fg_color)

    # 图形扭曲参数
    params = [1 - float(random.randint(1, 2)) / 100,
              0,
              0,
              0,
              1 - float(random.randint(1, 10)) / 100,
              float(random.randint(1, 2)) / 500,
              0.001,
              float(random.randint(1, 2)) / 500
              ]
    img = img.transform(size, Image.PERSPECTIVE, params)  # 创建扭曲

    img = img.filter(ImageFilter.EDGE_ENHANCE_MORE)  # 滤镜，边界加强（阈值更大）

    return img, strs


def create_lines(draw, n_line, width, height): # (draw, (1, 2), 120, 30)
    '''绘制干扰线'''
    line_num = random.randint(n_line[0], n_line[1])  # 干扰线条数
    for i in range(line_num):
        # 起始点
        begin = (random.randint(0, width), random.randint(0, height))
        # 结束点
        end = (random.randint(0, width), random.randint(0, height))
        draw.line([begin, end], fill=(0, 0, 0))


def create_points(draw, point_chance, width, height): #(draw, 2, 120, 30)
    '''绘制干扰点'''
    chance = min(100, max(0, int(point_chance)))  # 大小限制在[0, 100]

    for w in xrange(width):
        for h in xrange(height):
            tmp = random.randint(0, 100)
            if tmp > 100 - chance:
                draw.point((w, h), fill=(0, 0, 0))


def create_strs(draw, chars, length, font_type, font_size, width, height, fg_color):
    #(draw, 2, 120, 30, "/home/jedrek/work_dir/my_project/myflask/astute.ttf", 18, 120, 30, (0, 0, 255))
    '''绘制验证码字符'''
    '''生成给定长度的字符串，返回列表格式'''
    c_chars = random.sample(chars, length)
    strs = ' %s ' % ' '.join(c_chars)  # 每个字符前后以空格隔开

    font = ImageFont.truetype(font_type, font_size)
    font_width, font_height = font.getsize(strs)

    draw.text(((width - font_width) / 3, (height - font_height) / 3), strs, font=font, fill=fg_color)

    return ''.join(c_chars)


def remove_old_code():
    code_list = os.listdir('./')
    for code in code_list:
        os.remove(code)


def get_validate_code():
    cur_path = os.getcwd()
    os.chdir('static/code_img/')
    remove_old_code()
    code_img = create_validate_code()
    code_img[0].save(code_img[1] + ".gif", "GIF")
    os.chdir(cur_path)
    return code_img[1]