Пример класса captcha на php (2)

/**
* CaptchaV2 File
* Generates CAPTCHA Numbers and Chars Image
* @author Albert Demeter <borex8@hotmail.com>
* @version 2.1
* GNU General Public License (Version 2.1, March 7th, 2006)
*
* based on Hadar Porat's Captcha Numbers class v.1.5 <hpman28@gmail.com>
*
* This program is free software; you can redistribute
* it and/or modify it under the terms of the GNU
* General Public License as published by the Free
* Software Foundation; either version 2 of the License,
* or (at your option) any later version.
*
* This program is distributed in the hope that it will
* be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*/

/**
* CaptchaNumbersV2 Class
* @access public
* @author Albert Demeter <borex8@hotmail.com>
* @version 2.0
*/

class CaptchaNumbersV2 {
  var $length = 6;
  var $font = 'fonts/arial.ttf';
  var $size = 15;
  var $angle = 10;
  var $type = 'png';
  var $height = 40;
  var $width = 80;
  var $grid = 7;
  var $string = '';
  var $captchaType = 'mixed';

  // automatically calculated based on the percent in the constructor
  var $dotsCount = 0;

  // background colors RED, GREEN and BLUE values (provide it as a number between 0-255)
  var $bgColorRed = 240;
  var $bgColorGreen = 240;
  var $bgColorBlue = 240;

  // if true then grid is drawn
  var $drawGrid = false;

  // if true then every grid line will have a different color
  var $randomGridColor = true;

  // if true then every letter will have a different color
  var $randomLetterColor = true;

  // fonts
  // there is feature of this script that it picks random fonts for each character displayed
  // you should define a fonts folder
  // a folder named fonts within this scripts directory is tested and working.
  var $fonts_folder = 'fonts/';
  // the range of font size of each letter displayed as pixels. if you choose them same,
  //    fonts will be at that exact size.
  var $font_size_min = 14;
  var $font_size_max = 16;
  // font angles are for placing the fonts at a random angle. high values of angles might result unexpected.
  var $font_angle_min = 0;
  var $font_angle_max = 15;

  /**
  * @return void
  * @param int $length string length
  * @param int $size font size
  * @param String $type image type
  * @param String $captchaType text contain digits, chars or mixed
  * @param int $dotsPercent random pixels generated in image
  * @desc generate the main image
  */
  function CaptchaNumbersV2($length = '', $size = '', $type = '', $captchaType = '', $dotsPercent = 10) {

    if ($length!='') $this -> length = $length;
    if ($size!='') $this -> size = $size;
    if ($type!='') $this -> type = $type;
    if ($captchaType!='') $this -> captchaType = $captchaType;

    $this -> width = $this -> length * $this -> size + $this -> grid + $this -> grid;
    $this -> height = $this -> size + (2 * $this -> grid);

    // dots count equals #% of all points in the image
    $this -> dotsCount = round(($this -> width * $this -> height) * $dotsPercent / 100);

    $this -> generateString();
  }

  /**
  * @return void
  * @desc display captcha image
  */
  function display() {
    $this -> sendHeader();
    $image = $this -> generate();

    switch ($this-> type) {
      case 'jpeg': imagejpeg($image); break;
      case 'png': imagepng($image); break;
      case 'gif': imagegif($image); break;
      default:   imagepng($image); break;
    }
  }

// following function is gathered from php.net, author is "fankounter@libero.it"
  // it is used for gathering the fonts from the spesicfied folder. I have modifeid it slightly
  function ls($__dir="./",$__pattern="*.*")
  {
    settype($__dir, "string");
    settype($__pattern, "string");
    $__ls = [];
    $__regexp = preg_quote($__pattern,"/");
    $__regexp = preg_replace("/[\\x5C][\x2A]/",".*",$__regexp);
    $__regexp = preg_replace("/[\\x5C][\x3F]/",".", $__regexp);
    if(is_dir($__dir))
     if(($__dir_h=@opendir($__dir))!==FALSE)
     {
     while(($__file=readdir($__dir_h))!==FALSE)
      if(preg_match("/^".$__regexp."$/",$__file))
      array_push($__ls,$__file);
     closedir($__dir_h);
     sort($__ls,SORT_STRING);
     }
    return $__ls;
  }

  // function picks a random font for each letter each time
  function random_font() {

    $fonts = $this -> ls($this -> fonts_folder, "*.ttf");

    $rand = mt_rand(0, sizeof($fonts)-1);

    $this -> font = $this -> fonts_folder.$fonts[$rand];
  }

  // the font size would be determined randomly within the limits defined above.
  function random_font_size() {

    $this -> size = mt_rand($this -> font_size_min, $this -> font_size_max );
  }

  // the angle would be determined randomly within the limits defined above.
  function random_font_angle() {

    $this -> angle = mt_rand($this -> font_angle_min, $this -> font_angle_max );
  }

  /**
  * @return Image
  * @desc generate the image
  */
  function generate() {
    $image = ImageCreate($this -> width, $this -> height) or die("Cannot Initialize new GD image stream");

    // colors
    $background_color = ImageColorAllocate($image, $this -> bgColorRed, $this -> bgColorGreen, $this -> bgColorBlue);
    if (!$this -> randomLetterColor)
    {
     $net_color_1 = ImageColorAllocate($image, 10, 200, 10);
     $net_color_2 = ImageColorAllocate($image, 200, 10, 10);
    }
    if (!$this -> randomLetterColor)
    {
     $stringcolor_1 = ImageColorAllocate($image, 150, 150, 150);
     $stringcolor_2 = ImageColorAllocate($image, 120, 120, 250);
    }

    if ($this -> drawGrid)
     for ($i = $this -> grid; $i < $this -> height; $i+=$this -> grid)
      {
      if ($this -> randomGridColor)
      {
       $net_color_1 = ImageColorAllocate($image, mt_rand(0,255), mt_rand(0,250), mt_rand(0,250));
       $net_color_2 = ImageColorAllocate($image, mt_rand(0,255), mt_rand(0,250), mt_rand(0,250));
      }
        if ($i%2) ImageLine($image, 0, $i, $this -> width, $i, $net_color_1);
          else ImageLine($image, 0, $i, $this -> width, $i, $net_color_2);
      }

    // make the text
    $str = $this -> getString();
    $x = $this -> grid;
    for($i = 0, $n = strlen($str); $i < $n; $i++)
    {
     if ($this -> randomLetterColor)
     {
      $stringcolor_1 = ImageColorAllocate($image, mt_rand(0,255), mt_rand(0,250), mt_rand(0,250));
      $stringcolor_2 = ImageColorAllocate($image, mt_rand(0,255), mt_rand(0,250), mt_rand(0,250));
     }
      $this -> random_font();
      $this -> random_font_size();
      $this -> random_font_angle();
       if ($i%2) ImageTTFText($image, $this -> size, $this -> angle, $x, $this -> size + $this -> grid - mt_rand(0, 5), $stringcolor_1, $this -> font, $str{$i} );
         else ImageTTFText($image, $this -> size, $this -> angle, $x, $this -> size + $this -> grid + mt_rand(0, 5), $stringcolor_2, $this -> font, $str{$i} );
      $x = $x + $this -> size;
    }

    // grid
    if ($this -> drawGrid)
     for ($i = $this -> grid; $i < $this -> width; $i+=$this -> grid)
      {
      if ($this -> randomGridColor)
      {
       $net_color_1 = ImageColorAllocate($image, mt_rand(0,255), mt_rand(0,250), mt_rand(0,250));
       $net_color_2 = ImageColorAllocate($image, mt_rand(0,255), mt_rand(0,250), mt_rand(0,250));
      }
        if ($i%2) ImageLine($image, $i, 0, $i, $this -> height, $net_color_1);
          else ImageLine($image, $i, 0, $i, $this -> height, $net_color_2);
      }

    for ($i = 0; $i < $this -> dotsCount; $i++)
    {
       $x = rand(0, $this -> width - 1);
      $y = rand(0, $this -> height - 1);
      $rgbIndex = imagecolorat($image, $x, $y);
      $rgb = imagecolorsforindex($image, $rgbIndex);
      //print $x . ' x ' . $y . ' : ' . $rgbIndex . '(' . $rgb['red'] . '-' . $rgb['green'] . '-' . $rgb['blue'] . ')<br>';

      // if background color create random pixel color
      if ($rgb['red'] == $this -> bgColorRed
           && $rgb['green'] == $this -> bgColorGreen
          && $rgb['blue'] == $this -> bgColorBlue)
      {
         $dotColor = ImageColorAllocate($image, mt_rand(0,255), mt_rand(0,255), mt_rand(0,255));
      }
      else
      {
         // not background color then generate a close shade color
        $rgb['red'] = $rgb['red'] + ((mt_rand(0,100) % 2) == 1 ? 1 : -1) * mt_rand(0, 255 - $rgb['red']);
        if ($rgb['red'] < 0 || $rgb['red'] > 255) $rgb['red'] = mt_rand(0, 255);

        $rgb['green'] = $rgb['green'] + ((mt_rand(0,100) % 2) == 1 ? 1 : -1) * mt_rand(0, 255 - $rgb['green']);
        if ($rgb['green'] < 0 || $rgb['green'] > 255) $rgb['green'] = mt_rand(0, 255);

        $rgb['blue'] = $rgb['blue'] + ((mt_rand(0,100) % 2) == 1 ? 1 : -1) * mt_rand(0, 255 - $rgb['blue']);
        if ($rgb['blue'] < 0 || $rgb['blue'] > 255) $rgb['blue'] = mt_rand(0, 255);

         $dotColor = ImageColorAllocate($image, $rgb['red'], $rgb['green'], $rgb['blue']);
      }
      ImageSetPixel($image, $x, $y, $dotColor);
    }

    return $image;
  }


  /**
  * @return String
  * @desc generate the string
  */
  function generateString() {
    $string = $this->create_random_value($this -> length, $this -> captchaType);
    $this -> string = $string;
    return true;
  }


  /**
  * @return void
  * @desc send image header
  */
  function sendHeader() {
    header('Content-type: image/' . $this -> type);
  }

  /**
  * @return String
  * @desc return the string
  */
  function getString() {
    return $this -> string;
  }


 function create_random_value($length, $type = 'mixed') {
  if ( ($type != 'mixed') && ($type != 'chars') && ($type != 'digits')) return false;

  $rand_value = '';
  while (strlen($rand_value) < $length) {
   if ($type == 'digits') {
    $char = mt_rand(0,9);
   } else {
    $char = chr(mt_rand(0,255));
   }
   if ($type == 'mixed') {
    if (preg_match('/^[a-z0-9]$/i', $char)) $rand_value .= $char;
   } elseif ($type == 'chars') {
    if (preg_match('/^[a-z]$/i', $char)) $rand_value .= $char;
   } elseif ($type == 'digits') {
    if (preg_match('/^[0-9]$/', $char)) $rand_value .= $char;
   }
  }

  return $rand_value;
 }
}