captcha

问题 I was trying to sign-up Twitter today and I noticed that their registration form does not have a captcha. The form URL is https://twitter.com/signup. I also noticed that they used an input like below. <input name="authenticity_token" type="hidden" value="ce803cee65a96aaa97bdf75da166599c3adc9ec8" /> what kind of method is this? Do they create a temp value in their database when a user access the registration form? and check it when a user submit the form? 回答1: authenticity_token is a feature

问题 I'm trying to add the captcha to the login form. My environment: Yii 2 php 5.4.45 TS IIS 10.0 Windows 10 In login.php , LoginForm.php and SiteController.php I added the following (shown only the relevant parts): backend\views\site\login.php: use yii\captcha\Captcha; ... <?= $form->field($model, 'captcha')->widget(Captcha::className()) ?> ... common\models\LoginForm.php: ... public $captcha; ... public function rules() { return [ ... [['username', 'password', 'captcha'], 'required'], ['captcha

问题 I'm working with my simple PHP captcha algorithm (http://www.source.ofitall.com/devel/captcha.php) and I have been struggling to try and adjust it to be the more attractive and easier to read, Google style captcha. Does anyone know of a function that will take in a GD image reference and bend/warp it, Google style? 回答1: If you can use ImageMagick on your server you might want to give this a try: convert koala.gif -background Blue -wave 10x64 wave.jpg UPDATE : If you aren't using some library

问题 I need a captcha for my form, and I am having some troubles with the server-side integration. The form takes in four types of data: name email comment. After making sure that none of them are empty, I want to verify the captcha. However, for some reason, it always returns success == false . Can somebody help me spotting what's wrong with my code? function validate($data) { $data = trim($data); $data = stripslashes($data); $data = htmlspecialchars($data); return $data; } $nameMsgErr =

问题 I'm initiating my first start-up. I can't stand attempting to read captchas when signing up for websites, don't want my users to. I looked for alternatives, and I found the checkbox captcha. How is this done, using JavaScript to load a checkbox, and validate it with the same code as would normally be used to make a sign up form? Thanks. 回答1: I looked at the example linked from the article you posted. At first glance, it seems like this can be easily bypassed. The checkbox captcha works on the

问题 Before I ask this question, let me mention I know there are several of the exact same questions on the site but I am afraid they can't help me out. Hi, Yesterday my ReCaptcha was working fine but now it's not. I am using the library provided by Google and using the proper code. I did not change any code since yesterday so it should still work. However, when I try to submit the form now the page returns Could not open socket . Edit: I just checked and fsockopen is enabled on my server. 回答1: I

问题 I am using the codeigniter * capctha * helper. The thing is I can not increase the font size of letters. I tried to do it by if ($use_font == FALSE) { $font_size = 6; $x = rand(0, $img_width/($length/2)); $y = 0; } else { $font_size = 20; $x = rand(0, $img_width/($length/1.5)); $y = $font_size+2; } but nothing happens, how can change the font size, please help. Thanks in advance. 回答1: You are changing the correct parameter, whether in the core file or the application/helpers file. Double

问题 There's this snazzy captcha that asks questions rather than displaying pictures. You can read about it at textcaptcha.com. Anyway. I want to use that with Ruby on Rails. A developer by the name of Matt Hutchinson wrote a Gem for easily connecting to the API. He has a set of instructions next to his source files on github. Anyway, It looks pretty simple but in trying to implement it I get this error every time: undefined method `acts_as_textcaptcha' for #<Class:0x104098508> Rails.root: /Users

问题 Im using tesseract-ocr package on Ubuntu Linux, I have been using it for a while and I think that in order to improve the accuracy of the OCR I only need a subset of letters from the alphabet. The letters I need are: 0123456789abcdefghijklmnopqrstuvwxyz and only that, not even capital letters, can anybody give me a hand on indicating tesseract to only match againts a subset of letters ? Thanks, 回答1: From the python-tesseract project page: import tesseract api = tesseract.TessBaseAPI() api

问题 I need to resolve captcha automatically to grab the public data from sites. I use python and opencv. I'm newbee in solving the images processing. After search, as a method to resolve captcha I came up with next. As the text in Captha uses group of related colours I try to use the HSV format and mask, then convert image to Grayscale and use Threshold (Adaptive_THRESH_MEAN_C) to remove noise from the image. But this is not enough to remove noise and provide automatic text recognition with OCR