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

IBM developerWorks: U2 PDO Driver Tutorial, Parts 1 & 2

Graham Bird's Blog: Extra-pretty URLs with slugs

Pádraic Brady's Blog: Extending the Mapper: Stars and Planets

Rob Allen's Blog: Hooks in Action Helpers

Rob Allen's Blog: Zend Framework Tutorial for 0.7


Community Events





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


developer list wordpress release introduction code testing refactor api series podcast install interview framework community language laravel opinion threedevsandamaybe unittest

All content copyright, 2014 PHPDeveloper.org :: info@phpdeveloper.org - Powered by the Solar PHP Framework