BotDetect PHP CAPTCHA Randomization Sample

PHP CAPTCHA validation
CAPTCHA
Reload the CAPTCHA codeSpeak the CAPTCHA code
 

Description

This sample project shows how to easily randomize various Captcha library parameters, beyond the basic image and sound style randomization used by default.

Randomly using different Captcha image and sound generation algorithms and other parameter values (such as code length and style) can significantly improve the Captcha security.

This is the recommended approach to Captcha property setting, since it takes full advantage of the 60 Captcha image and 10 Captcha sound generation algorithms shipped with BotDetect, as well as built-in randomization features.

Setting Captcha control properties in the CaptchaConfig.php file also reduces the amount of Session state used by the library.

Beta Release Warning

BotDetect PHP Captcha Library Beta is a work in progress, and we need you to guide our efforts towards a polished product. Please let us know if you encounter any bugs, implementation issues, or a usage scenario you would like to discuss.

Free Version Limitations

  • The free version of BotDetect includes a randomized BotDetect™ trademark in the background of 50% of all Captcha images generated.
  • It also has limited sound functionality, replacing the CAPTCHA sound with "SOUND DEMO" for randomly selected 50% of all CAPTCHA codes.
  • Lastly, the bottom 10 px of the CAPTCHA image are reserved for a link to the BotDetect website.

These limitations are removed if you upgrade your BotDetect license.