This tutorial tell you how to create your own captcha image.
You should follow these steps:
You should follow these steps:
- Copy the code below and save it as "create_image.php"
<?php
//Start the session so we can store what the security code actually is
session_start();
//Send a generated image to the browser
Create_Captcha_Images();
exit();
function Create_Captcha_Images() {
$width='135';
$height='30';
//Let's generate a totally random string using md5
$md5_hash = md5(rand(0,999));
//We don't need a 32 character long string so we trim it down to 5
$code = substr($md5_hash, 15, 5);
//Set the session to store the security code
$_SESSION["security_code"] = $code;
//create image resource using width and height
$image = @imagecreate($width, $height) or die('Cannot initialize new GD image stream');
/* set the colours */
$background_color = imagecolorallocate($image, 255, 255, 255);
$text_color = imagecolorallocate($image, 0, 0, 0);
$noise_color = imagecolorallocate($image, 100, 120, 180);
/* generate random dots in background */
for( $i=0; $i<110; $i++ ) {
imagefilledellipse($image, mt_rand(0,$width), mt_rand(0,$height), 1, 1, $noise_color);
}
/* generate random lines in background */
for( $i=0; $i<250; $i++ ) {
imageline($image, mt_rand(0,$width), mt_rand(0,$height), mt_rand(0,$width), mt_rand(0,$height), $noise_color);
}
// add white string to box with params: image, font (1-5), x, y, string and color
imagestring($image, 5, 40, 7, $code, $text_color);
/* output captcha image to browser */
header('Content-Type: image/jpeg');
imagejpeg($image);
imagedestroy($image);
}
?> - Copy the code below and save it as "contact_us.php".
<?php
session_start();
if(isset($_POST['submit']))
{
$image = $_POST['antibot_input_str'];
if($image == $_SESSION["security_code"])
{
echo 'Your Entered code has matched go ahead. e.g. store your form data into database';
}
else
{
$mail_sent = 'Your Entered code does not match';
}
}
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>
<body>
<form method="post" action="contact_us.php">
<table align="center">
<tr valign="middle">
<td class="FormButton">First name</td>
<td><font class="Star">*</font></td>
<td nowrap="nowrap">
<input type="text" value="" maxlength="32" size="32" name="firstname" id="firstname">
</td>
</tr>
<tr valign="middle">
<td class="FormButton">Last name</td>
<td><font class="Star">*</font></td>
<td nowrap="nowrap">
<input type="text" value="" maxlength="32" size="32" name="lastname" id="lastname">
</td>
</tr>
<tr>
<td class="iv-box-descr" colspan="3">Type the characters you see in the picture. (If you do not see any picture here, please enable images in your web browser options and refresh this page):</td>
</tr>
<tr>
<td class="iv-box" colspan="2">
<div class="iv-img">
<img id="imgCaptcha" src="create_image.php"/><br>
<a onclick="
document.getElementById('imgCaptcha').src = 'create_image.php?' + Math.random();
return false;
" href="javascript:void(0);">Get a different code</a>
</div>
<br> </td>
<td class="iv-box">
<input type="text" name="antibot_input_str">
</td>
</tr>
<tr valign="middle">
<td> </td>
<td> </td>
<td>
<input id="insert" name="submit" type="submit" value="Submit" />
</td>
</tr>
</table>
</form>
</body>
</html>
