bypass easy captcha with PHP

[-]PHP

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<?php // CAPTCHA Bypass Code (Works 99%) // by Napalm // // License: http://creativecommons.org/licenses/by-sa/2.0/uk/ //  // CAPTCHA Location: http://www.xovie.us/captcha/captcha.php //   function  imageconverttruecolor(&$image) {     $width = imagesx($image);     $height = imagesy($image);        $final = imagecreatetruecolor($width, $height);     imagecopy($final, $image, 0, 0, 0, 0, $width, $height);     imagedestroy($image);   $image = $final; }   // load images   $background = imagecreatefrompng("captcha.png"); $lettersimg = imagecreatefrompng("letters.png"); $captcha = imagecreatefrompng("http://www.xovie.us/captcha/captcha.php"); imageconverttruecolor($background);imageconverttruecolor($lettersimg); imageconverttruecolor($captcha); // first parse - difference test and pixel save $pixels = array(); for($x = 0; $x < imagesx($captcha); $x++) {        for($y = 0; $y < imagesy($captcha); $y++)     {               $src = imagecolorat($background, $x, $y);               $dst = imagecolorat($captcha, $x, $y);              if(!($src == 0 && $dst == 0) && ($src == $dst))                  $pixels[$x][$y] = 0xFFFFFF;                else $pixels[$x][$y] = 0x000000;           } } imagedestroy($background);   // second parse - filter out pixel noise   for($p = 0; $p < 3; $p++) {     // 3 noise parses     for($x = 0; $x <  imagesx($captcha); $x++)     {               for($y = 0; $y < imagesy($captcha); $y++)         {                       $filterpixel = true;                        if(!$pixels[$x-1][$y-1] && !$pixels[$x+0][$y-1] && !$pixels[$x+1][$y-1])             $filterpixel = false;             // top                       if(!$pixels[$x+1][$y-1] && !$pixels[$x+1][$y+0] && !$pixels[$x+1][$y+1])             $filterpixel = false;             // right                     if(!$pixels[$x-1][$y+1] && !$pixels[$x+0][$y+1] && !$pixels[$x+1][$y+1])             $filterpixel = false;             // bottom                        if(!$pixels[$x-1][$y-1] && !$pixels[$x-1][$y+0] && !$pixels[$x-1][$y+1])             $filterpixel = false;             // left                      if($filterpixel) $pixels[$x][$y] = 0xFFFFFF;                }       } } for($x = 0; $x < imagesx($captcha); $x++) {     $pixels[$x][0] = 0xFFFFFF;      $pixels[$x][1] = 0xFFFFFF;      $pixels[$x][imagesy($captcha) - 1] = 0xFFFFFF;      $pixels[$x][imagesy($captcha) - 2] = 0xFFFFFF; } for($y = 0; $y < imagesy($captcha); $y++) {        $pixels[0][$y] = 0xFFFFFF;  $pixels[1][$y] = 0xFFFFFF;      $pixels[imagesx($captcha) - 1][$y] = 0xFFFFFF;      $pixels[imagesx($captcha) - 2][$y] = 0xFFFFFF; } for($x = 50; $x < 54; $x++) {      for($y = 2; $y < 5; $y++)     {               $pixels[$x][$y] = 0xFFFFFF;     } } // third parse - rebuild image (just for show) for($x = 0; $x < imagesx($captcha); $x++) {       for($y = 0; $y < imagesy($captcha); $y++)     {               imagesetpixel($captcha, $x, $y, 0xFFFFFF);              if(($x % 3) == 0 && ($y % 3) == 0 && $pixels[$x][$y] == 0)         {                     imagesetpixel($captcha, $x, $y, 0xFF0000);              }       } } // fourth parse - basic ocr (slow) :-( $letters = 'ABCE'; $ocr = ''; for($x1 = 0; $x1 < imagesx($captcha) - 25; $x1++) {      for($y1 = 0; $y1 < imagesy($captcha) - 27; $y1++)     {               $score = array();               for($letter = 0; $letter < 4; $letter++)         {                        for($x2 = 0; $x2 <  25; $x2++)             {                              for($y2 = 0; $y2 < 27; $y2++)                 {                                       $color = imagecolorat($lettersimg, ($letter * 25) + $x2, $y2);                                      if($pixels[$x1 + $x2][$y1 + $y2] == $color && $color == 0)                     $score[$letter][0]++;                                        if($color == 0) $score[$letter][1]++;                               }                       }               }               $found = -1; $highest = 0;              for($letter = 0; $letter < 4; $letter++)         {                        $result = (($score[$letter][1] / 100) * 90);                       if($score[$letter][0] >= $result)             {                               $result = ($score[$letter][0] - $result);                               if($result > $highest)                 {                                      $highest = $result;                                     $found = $letter;                               }                       }               }               if($found > -1)         {                     $ocr .= $letters[$found];                       $x1  += 10;             }               unset($score);      } } imagedestroy($lettersimg);unset($pixels); // last of all output header('Content-Type: image/png'); imagestring($captcha, 2, 0, 0, $ocr, 0); imagepng($captcha); imagedestroy($captcha); ?> from : http://www.rohitab.com/discuss/topic/26430-how-to-bypass-captcha/