<?php

  error_reporting(E_ALL & ~E_NOTICE);
  session_start();
  header("Content-type: image/jpeg");

  //if (isset($_SESSION["SecurityCode"]) && $_SESSION["SecurityCode"] != "") {
  //    $_string = $_SESSION["SecurityCode"];
  //} else {
  $_string = RndCode();
  $_SESSION["SecurityCode"] = strtoupper($_string);
  //}

  $x=100;
  $y=35;

  $im=imagecreatetruecolor($x,$y);
  $text_color=imagecolorallocate($im, 0, 0, 0);
  $bg_color=imagecolorallocate($im, 255, 255, 255);
  imagefilledrectangle($im, 1, 1, $x-2, $y-2, $bg_color);
  $font=realpath("./arial.ttf"); // â íåêîòîðûõ ñëó÷àÿõ ìîæíî óêàçàòü ïðîñòî arial.ttf

  mt_srand((double)microtime() * 1000000);

  $size=18;

  imagettftext($im, $size, 10, 16, 32, $text_color, $font, $_string);

  for($i=1;$i<20;$i++){
	$px=mt_rand(0,$x);
	$py=mt_rand(0,$y);
	imageline($im, $px, $py, $px+mt_rand(0,20)-5, $py+mt_rand(0,20)-5, $text_color);
  }

  imagejpeg($im,'', 80);
  imagedestroy($im);

  function RndCode() {
	$strSymbols = "2345689ERYPADFHKXBNM";
	$strRet = "";
	$i = 0;

	mt_srand((double)microtime() * 1000000);

	while ($i < 4) 
	{
		$strRet .= $strSymbols[mt_rand(0, strlen($strSymbols) - 1)];
		$i++;
	}
	return $strRet;
  }

?>