<?
/**
 * Simple Image Captcha System for websites
 *
 * @author Joao Romao <http://jromao.com>
 * @creation-date 26/06/09
 * Distribute at your will, leave the header, add your name if you change anything
 */
		$cars = array("Q","q","W","w","E","e","R","r","T","t","Y","y","U","u","I","i","O","o","P","p","A","a","S","s","D","d","F","f","G","g","H","h","J","j","K","k","L","l","Z","z","X","x","C","c","V","v","B","b","N","n","M","m","1","2","3","4","5","6","7","8","9","0");
		$string = "";

		header("Content-type: Image/png");
		$img = imagecreate(120,40);
		$background_color = imagecolorallocate($img, mt_rand(135,255),mt_rand(135,255),mt_rand(135,255));

		$nlinhas = mt_rand(0,4);
		for ($i = 0; $i < $nlinhas; $i++) {
		$cor_texto = imagecolorallocate($img,mt_rand(0,128),mt_rand(0,128),mt_rand(0,128));
			imageline($img, mt_rand(0,120), mt_rand(0,40), mt_rand(0,120), mt_rand(0,40), $cor_texto);
		}
			
		for ($i = 0; $i < 6; $i++) {
			$cor_texto = imagecolorallocate($img,mt_rand(0,128),mt_rand(0,128),mt_rand(0,128));
			$car = $cars[mt_rand(0,61)];
			$string .= $car;
			imagestring($img, mt_rand(2,5),mt_rand($i*20+1, $i*20+10), mt_rand(2,20), $car, $cor_texto);
		}

		$_SESSION['CAPTCHA_IMAGE'] = strtolower($string);
		imagepng($img);
		imagedestroy($img);
?>