BasicCaptcha

A simple php class to generate and check captcha values.

Notes:
- Single file class, no database needed.
- The check is not case sensitive.
- A token can be used within 1 hour (customizable static property).

Usage

  1. include the class in your project and assign a new own value to the static class property $key.
  2. use $formToken = BasicCaptcha::generateFormToken(); to obtain a new token to be sent alongside the captcha value inserted by the form user.
  3. use $captchaValue = BasicCaptcha::generate($formToken);, passing the previously obtained form token, to obtain a new captcha value.
  4. use $captchaBase64 = BasicCaptcha::getB64($captchaValue);, passing the previously obtained captcha value, to obtain a base64 encoded image of the captcha value.
  5. in a form, add an <img src="data:image/png;base64,<?php echo $captchaBase64;?>"> node, needed to show the user the captcha image.
  6. in the same form, add a <input type="text" maxlength="8" name="captcha" placeholder="Input the captcha code" required /> input, needed to let the user input the captcha code.
  7. in the form processing page, use $isCaptchaValid = BasicCaptcha::verify($captcha,$formToken); making sure both the arguments are obtained from the post submission, to check if the captcha input is valid.

Audio player

You can obtain an array of base64 audios by using BasicCaptcha::getB64($captchaValue,'audio','en');
on your page, add all the obtained audios using hidden audio elements: <audio style="display:none;" class="captcha_audio" src="data:audio/mpeg;base64,<?php echo $a; ?>"></audio>
and a button to play them all: <button type="button" id="captcha_audio_button"> Play captcha audio </button>
then include the BasicCaptcha.js class, and use it as follows : 

let captcha = new BasicCaptcha({'wrapperQuery':'#captcha-wrapper' ,'logEnabled':true ,'audioPauseDurationMs':800});
captcha.setAudioNodes('.captcha_audio');
captcha.setAudioPlayer('#captcha_audio_button');

Demo

You can try a simple form implementation including demo.php, BasicCaptcha.php and BasicCaptcha.js in your project. Don’t forget to remove the file when no more needed.

screenshots

image