aedating security image hakkında

<?php
require_once( "../inc/header.inc.php" );
ob_start();
session_start();
$chars = array("a","A","b","B","c","C","d","D","e","E","f","F","g","G","h","H","i","I","j","J",
			   "k","K","L","m","M","n","N","o","p","P","q","Q","r","R","s","S","t","T",
			   "u","U","v","V","w","W","x","X","y","Y","z","Z","2","3","4","5","6","7","8","9");
$textstr = '';
for ($i = 0, $length = 8; $i < $length; $i++) {
   $textstr .= $chars[rand(0, count($chars) - 1)];
}
$hashtext = md5($textstr);
$tmpname = $hashtext.'.png';
$_SESSION['strSec'] = $hashtext;
$bgurl = rand(1, 3);
$cmd  = $CONVERT;
$cmd .= ' '.$dir['root'].'simg/images/bg'.$bgurl.'.png';
$cmd .= ' -crop 200x35+'. rand(0,180) . '+' . rand(0,315);
$cmd .= ' '.$dir['root'].'tmp/bg'.$hashtext.'.png';
exec($cmd);

$im = $dir['root']."tmp/bg".$hashtext.".png";
$font = $dir['root']."simg/verdana.ttf";
$size = rand(24, 36);
$hexValues = array('0','1','2','3','4');
$numHex = count($hexValues);
$color = '';
for ($i = 0; $i < 6; $i++) {
	$color .= $hexValues[rand(0, $numHex-1)];
}
$gravities = array('West', 'Center', 'East');
$gravity = $gravities[rand(0, count($gravities)-1)];
$angle = rand(-10, 10);
$cmd  = $CONVERT;
$cmd .= ' -font "'.$font.'"';
$cmd .= ' -fill "#'.$color.'"';
$cmd .= ' -pointsize '.$size;

// $cmd .= ' -gravity "'.$gravity.'"'; // uncomment for old ImageMagick version
// $cmd .= ' -draw "text 1,0 \''.$textstr.'\'"'; // uncomment for old ImageMagick version
$cmd .= ' -draw "text '. rand(1, 30) .','. $size .' \''.$textstr.'\'"'; // comment for old ImageMagick version
$cmd .= ' -rotate '.$angle;
// $cmd .= ' '.$im.' '.$dir['root'].'tmp/'.$tmpname;
exec($cmd);
unlink($im);
header("Content-Type: image/png");
print fread(fopen($dir['root'].'tmp/'.$tmpname, 'r'), filesize($dir['root'].'tmp/'.$tmpname));
unlink($dir['root'].'tmp/'.$tmpname);
ob_end_flush();
?>

<?php
require_once( "../inc/header.inc.php" );
ob_start();
session_start();
$chars = array("a","A","b","B","c","C","d","D","e","E","f","F","g","G","h","H","i","I","j","J",
			   "k","K","L","m","M","n","N","o","p","P","q","Q","r","R","s","S","t","T",
			   "u","U","v","V","w","W","x","X","y","Y","z","Z","2","3","4","5","6","7","8","9");
$textstr = '';
for ($i = 0, $length = 8; $i < $length; $i++) {
   $textstr .= $chars[rand(0, count($chars) - 1)];
}
$hashtext = md5($textstr);
$_SESSION['strSec'] = $hashtext;

$img_number = imagecreate(47,17);
$backcolor = imagecolorallocate($img_number,244,244,244);
$textcolor = imagecolorallocate($img_number,0,0,0);

imagefill($img_number,0,0,$backcolor);

Imagestring($img_number,50,1,1,$textstr,$textcolor);
header("Content-type: image/png");
imagejpeg($img_number);


ob_end_flush();
?>

<?php 
require_once( "../inc/header.inc.php" ); 
ob_start(); 
session_start(); 
$chars = array("a","A","b","B","c","C","d","D","e","E","f","F","g","G","h","H","i","I","j","J", 
               "k","K","L","m","M","n","N","o","p","P","q","Q","r","R","s","S","t","T", 
               "u","U","v","V","w","W","x","X","y","Y","z","Z","2","3","4","5","6","7","8","9"); 
$textstr = ''; 
for ($i = 0, $length = 8; $i < $length; $i++) { 
   $textstr .= $chars[rand(0, count($chars) - 1)]; 
} 
$hashtext = md5($textstr); 
$_SESSION['strSec'] = $hashtext; 

$img_number = imagecreate(120,17); 
$backcolor = imagecolorallocate($img_number,244,244,244); 
$textcolor = imagecolorallocate($img_number,0,0,0); 

imagefill($img_number,0,0,$backcolor); 

Imagestring($img_number,50,1,1,$textstr,$textcolor); 
header("Content-type: image/png"); 
imagejpeg($img_number); 


ob_end_flush(); 
?>