说明：  一个PHP验证码生成代码，ShonenPunk.ttf字体是自定义的字体，如果不喜欢这个字体，那就自己换个地址，PHP代码里做相应修改就可以了。除此之外，本验证生成类还支持session名称自定义；验证码图片透明度自定义；验证码中的字符个数随机；字体大小自定义；字符与图片边距自定义
(An authentication code generated PHP code, ShonenPunk.ttf font is a custom font, if you do not like the font, then himself another address, PHP code can be modified accordingly. In addition, this also supports the session to verify the generated class name of the custom Captcha Image transparency custom number of characters in a random verification code font size to customize margins custom characters and pictures)