captcha

I would like to write a Python script that would generate a 3D CAPTCHA like this one: Which graphics libraries can I use? Source: ocr-research.org.ua Paul There are many approaches. I would personally create the image in Python Imaging Library using ImageDraw 's draw.text, convert to a NumPy array (usint NumPy's asarray ) then render with Matplotlib . (Requires Matplotlib maintenance package ). Full code (in 2.5): import numpy, pylab from PIL import Image, ImageDraw, ImageFont import matplotlib.axes3d as axes3d sz = (50,30) img = Image.new('L', sz, 255) drw = ImageDraw.Draw(img) font =

Does anyone have any recommendations for CAPTCHA components for use in ASP.NET projects? alexn I've been using recaptcha for a couple of sites with great success. I really recommend it. There is a recaptcha control for asp.net here . I've also used this captcha with success. Before you evaluate any captcha solutions you should develop a clear profile of your users. Needless to say, any captcha solution is going to make your site harder to use. If your users are older with vision difficulties deciphering a captcha can be extremely difficult if not impossible. Random characters vs real words,

What is appropriate way to integrate SpringSecurity with Capcha ? I have following use case : When user will tries to login, if we he failed to login N times, captcha will be displayed, so authentication will be using three parameters : username, password, captcha. But Spring Security doesn't support built in Captcha handling. I just start thinking about implementation. And have following variants: Adding separate security filter in Spring Security filter stack, Entirely rewrite AuthenticationProcessingFilter to support some Captcha Use some programmatic authentication with interception

I'd like to implement a captcha in a Rails project for a form submission, but I'm not sure what to go with. I'm inclining towards simplicity of implemention, and reliability when in use, over it being too sophisticated, as my application doesn't require too high a level of security. Anyone have any recommendations? The easiest way to add a CAPTCHA to your Rails application is using Ambethia reCAPTCHA : 1. Installation: config.gem "ambethia-recaptcha", :lib => "recaptcha/rails", :source => "http://gems.github.com" You can install it as a plugin, too, if you like. 2. Get a reCAPTCHA account: You

What is a good invisible captcha? My site requires JavaScript so anything which requires that is fine. Add a new input field, label it "Please leave blank", hide it using CSS, and ignore the post if that field is filled in. Something like this: <style type='text/css'> #other_email_label, #other_email { display: none; } </style> ... <form action='mail'> <label id='other_email_label' for='other_email'>Please leave blank:</label> <input type='text' name='other_email' id='other_email'> ... </form> So a human being won't see that field (unless they have CSS turned off, in which case they'll see the

I want to implement user registration using captcha in Django. The workflow of django-registration app is a great, but it doesn't have captcha. What captcha would you recommend to use with it? Are there some other variants of registration+captcha or useful links on the topic? This should work with Django-1.1 and don't be too hard to install. django-registration is pretty extendable. One way to extend it is to provide a custom registration form. I'd recommend to use reCaptcha , e.g. with the widget and form field from here ( archived ). Then it is as simple as writing a custom form class and

说到抓包分析，最简单的办法莫过于在客户端直接安装一个Wireshark或者Fiddler了，但是有时候由于客户端开发人员（可能是第三方）知识欠缺或者其它一些原因，无法顺利的在客户端进行抓包分析，这种情况下怎么办呢？ 本文中，我们将给大家介绍在服务端进行抓包分析的方法，使用tcpdump抓包，配合Wireshark对HTTP请求进行分析，非常简单有效。 本文将会持续修正和更新，最新内容请参考我的 GITHUB 上的 程序猿成长计划 项目，欢迎 Star，更多精彩内容请 follow me 。 使用tcpdump在服务器抓包 在服务端进行抓包分析，使用tcpdump tcpdump -tttt -s0 -X -vv tcp port 8080 -w captcha.cap 这里的参数是这样的 -tttt 输出最大程度可读的时间戳 -s0 指定每一个包捕获的长度，单位是byte，使用-s0可以捕获整个包的内容 -X 以hex和ASCII两种形式显示包的内容 -vv 显示更加多的包信息 tcp 指我们只捕获tcp流量 port 8080 指我们只捕获端口8080的流量 -w captcha.cap 指定捕获的流量结果输出到captcha.cap文件，便于分析使用 关于tcpdump更加高级的用法，可以参考 tcpdump简明教程 上述命令会保持运行，并将结果输出到 captcha.cap

I have a user registration form, in which I am trying to display a Captcha image by using Yii widget CCaptcha, however my image link appears broken, Controller file: public function actions() { return array( // captcha action renders the CAPTCHA image displayed on the contact page 'captcha'=>array( 'class'=>'CCaptchaAction', 'backColor'=>0xFFFFFF, ), ); } Model File: public function rules() { return array( array('verifyCode','captcha','allowEmpty'=>!CCaptcha::checkRequirements(),'on'=>'insert'), ); } And view file: <?php if(CCaptcha::checkRequirements()): ?> <div class="row"> <?php echo $form-