News Feed
Sections




News Archive
Looking for more information on how to do PHP the right way? Check out PHP: The Right Way

SitePoint PHP Blog:
Simple Captchas with PHP and GD
March 07, 2014 @ 12:05:38

On the SitePoint PHP blog there's a new post by Mahul Jain looking at a simple way to create CAPTCHA images in PHP using the built-in GD libraries.

By now, we've all encountered captcha images in online forms. Captchas are a necessary evil, and this article will teach you how they're made. Please note that while there are better, automatic third party solutions for captchas out there such as ReCaptcha, this tutorial aims merely to explain and demonstrate how such technology actually works. We won't be explaining what captchas actually are, as it's assumed to be common knowledge and already covered in greater detail elsewhere.

He walks you through the whole process of making the sample CAPTCHA (like this one):

  • Display an empty image on the browser
  • Create a shape
  • Generate random lines
  • Generate random dots
  • Generate random text

There's screenshots all along the way too for reference as to what your result should look like. You can download the full code over on GitHub.

0 comments voice your opinion now!
captcha gd tutorial introduction

Link: http://www.sitepoint.com/simple-captchas-php-gd/

blog comments powered by Disqus

Similar Posts

Stuart Herbert's Blog: Series: Beyond Frameworks

Developer Tutorials: Zend Framework Tutorial

NetTuts.com: Elevate Your PHP to the Cloud

Jeremy Johnstone's Blog: PHP parser for OS X plist XML files

NETTUTS.com: How to Authenticate Users With Facebook Connect


Community Events

Don't see your event here?
Let us know!


api series interview version podcast example community library framework performance conference voicesoftheelephpant opinion symfony2 php7 laravel list release extension introduction

All content copyright, 2015 PHPDeveloper.org :: info@phpdeveloper.org - Powered by the Solar PHP Framework