<?php
session_start();
$_SESSION = array();

include("simple-php-captcha.php");
$_SESSION['captcha'] = simple_php_captcha();

?>
<!DOCTYPE html>
<html>
<head>
    <title>Example &raquo; A simple PHP CAPTCHA script</title>
    <style type="text/css">
    	pre {
    		border: solid 1px #bbb;
    		padding: 10px;
    		margin: 2em;
    	}
    	
    	img {
    		border: solid 1px #ccc;
    		margin: 0 2em;
    	}
    </style>
</head>
<body>
    <h1>
        CAPTCHA Example
    </h1>
    
    <h2>Usage</h2>
    
    <p>
    	The following code will prepare a CAPTCHA image and keep the code in a session
    	variable for later use:
    </p>
    
<pre>
&lt;?php
session_start();
include("simple-php-captcha.php");
$_SESSION['captcha'] = simple_php_captcha();
?&gt;
</pre>
    
    <p>
    	After the call to <code>simple_php_captcha()</code> above, 
    	<code>$_SESSION['captcha']</code> will be something like this:
    </p>
    
<pre>
<?php
print_r($_SESSION['captcha']);
?>
</pre>
    
    <p>
    	To display the CAPTCHA image, create an HTML <code>&lt;img&gt;</code> using 
    	<code>$_SESSION['captcha']['image_src']</code> as the <code>src</code> attribute:
    </p>
    
    <p>
    	<?php
    	echo '<img src="' . $_SESSION['captcha']['image_src'] . '" alt="CAPTCHA code">';
    	
    	?>
    </p>
    
    <p>
    	To verify the CAPTCHA value on the next page load (or in an AJAX request), test 
    	against  <code>$_SESSION['captcha']['code']</code>. You can use 
    	<code>strtolower()</code> or <code>strtoupper()</code> to perform a 
    	case-insensitive match.
    </p>
    
    <h2>Configuration</h2>
    <p>
    	Configuration is easy and all values are optional. To specify one or more options, 
    	do this:
    </p>
    
<pre>
&lt;?php

$_SESSION['captcha'] = simple_php_captcha( array(
	'min_length' => 5,
	'max_length' => 5,
	'backgrounds' => array(image.png', ...),
	'fonts' => array('font.ttf', ...),
	'characters' => 'ABCDEFGHJKLMNPRSTUVWXYZabcdefghjkmnprstuvwxyz23456789',
	'min_font_size' => 28,
	'max_font_size' => 28,
	'color' => '#666',
	'angle_min' => 0,
	'angle_max' => 10,
	'shadow' => true,
	'shadow_color' => '#fff',
	'shadow_offset_x' => -1,
	'shadow_offset_y' => 1
));

&gt;
</pre>
    
    <h2>Notes</h2>
    <ul>
    	<li>
    		<strong>Important!</strong> Make sure you call <code>session_start()</code> before 
    		calling the <code>simple_php_captcha()</code> function
    	</li>
    	<li>
    		Requires PHP GD2 library
    	</li>
    	<li>
    		Backgound images must be in PNG format
    	</li>
    	<li>
    		Fonts must be either TTF or OTF
    	</li>
    	<li>
    		Backgrounds and fonts must be specified using their full paths (tip: use 
    		<code>$_SERVER['DOCUMENT_ROOT'] . '/' . [path-to-file]</code>)
    	</li>
    	<li>
    		Angles should not exceed approximately 15 degrees, as the text will sometimes 
    		appear outside of the viewable area
    	</li>
    	<li>
    		Creates a function called <code>simple_php_captcha()</code> in the global namespace
    	</li>
    	<li>
    		Uses the <code>$_SESSION['simple-php-captcha']</code> session variable
    	</li>
    </ul>
    
</body>
</html>