basic CAPTCHA Image

[Fallen]

Well I was making a site and had to create some sort of CAPTCHA,

PHP Code:

<?php
session_start();
mt_srand(time());
$my_img = imagecreate( 200, 40 );
$bg = imagecolorallocate($my_img, 0, 0, 0);
$blue  = imagecolorallocate($my_img,   0,   0, 255);
$gray  = imagecolorallocate($my_img, 169, 169, 169);
$wild  = imagecolorallocate($my_img, mt_rand(1,255), mt_rand(1,255), mt_rand(1,255));
imagesetthickness ( $my_img, 5 );
imageline( $my_img, 30, 45, 165, 10, $gray );
imageline( $my_img, 35, 15, 122, 1, $blue );
$str = substr(md5(microtime()*mktime()),0,mt_rand(5,7));
$_SESSION['captcha'] = $str;
imagestring( $my_img, 4, mt_rand(20,30), mt_rand(15,25), $str, $wild );
header( "Content-type: image/png" );
imagepng( $my_img );
imagedestroy( $my_img );
?>

Seems to work decently, It generates a very random string, that is 5 to 7 characters long

PHP Code:

$str = substr(md5(microtime()*mktime()),0,mt_rand(5,7)); 


And uses a random color aswell as a somewhat random posistion, and throws 2 lines through the image then the captcha string is stored in $_SESSION['captcha']

[faviouz]

Pretty neat. Thanks for sharing the code.

[Josh[y]]

Very nice, this would be useful for login form, email forms, etc.

[DevilKid]

Thanks for sharing. I hope to make a website in future. Hopefully it helps.

[phatuis]

Thanks for sharing the code, might use this for a registration form I might create, once again thanks.