interface/modules/zend_modules/library/Zend/Captcha/Image.php

   1 <?php
   2 /**
   3  * Zend Framework (http://framework.zend.com/)
   4  *
   5  * @link      http://github.com/zendframework/zf2 for the canonical source repository
   6  * @copyright Copyright (c) 2005-2013 Zend Technologies USA Inc. (http://www.zend.com)
   7  * @license   http://framework.zend.com/license/new-bsd New BSD License
   8  */
   9
  10 namespace Zend\Captcha;
  11
  12 use DirectoryIterator;
  13 use Zend\Captcha\Exception;
  14 use Zend\Stdlib\ErrorHandler;
  15
  16 /**
  17  * Image-based captcha element
  18  *
  19  * Generates image displaying random word
  20  */
  21 class Image extends AbstractWord
  22 {
  23     /**
  24      * Directory for generated images
  25      *
  26      * @var string
  27      */
  28     protected $imgDir = "public/images/captcha/";
  29
  30     /**
  31      * URL for accessing images
  32      *
  33      * @var string
  34      */
  35     protected $imgUrl = "/images/captcha/";
  36
  37     /**
  38      * Image's alt tag content
  39      *
  40      * @var string
  41      */
  42     protected $imgAlt = "";
  43
  44     /**
  45      * Image suffix (including dot)
  46      *
  47      * @var string
  48      */
  49     protected $suffix = ".png";
  50
  51     /**
  52      * Image width
  53      *
  54      * @var int
  55      */
  56     protected $width = 200;
  57
  58     /**
  59      * Image height
  60      *
  61      * @var int
  62      */
  63     protected $height = 50;
  64
  65     /**
  66      * Font size
  67      *
  68      * @var int
  69      */
  70     protected $fsize = 24;
  71
  72     /**
  73      * Image font file
  74      *
  75      * @var string
  76      */
  77     protected $font;
  78
  79     /**
  80      * Image to use as starting point
  81      * Default is blank image. If provided, should be PNG image.
  82      *
  83      * @var string
  84      */
  85     protected $startImage;
  86
  87     /**
  88      * How frequently to execute garbage collection
  89      *
  90      * @var int
  91      */
  92     protected $gcFreq = 10;
  93
  94     /**
  95      * How long to keep generated images
  96      *
  97      * @var int
  98      */
  99     protected $expiration = 600;
 100
 101     /**
 102      * Number of noise dots on image
 103      * Used twice - before and after transform
 104      *
 105      * @var int
 106      */
 107     protected $dotNoiseLevel = 100;
 108
 109     /**
 110      * Number of noise lines on image
 111      * Used twice - before and after transform
 112      *
 113      * @var int
 114      */
 115     protected $lineNoiseLevel = 5;
 116
 117     /**
 118      * Constructor
 119      *
 120      * @param  array|\Traversable $options
 121      * @throws Exception\ExtensionNotLoadedException
 122      */
 123     public function __construct($options = null)
 124     {
 125         if (!extension_loaded("gd")) {
 126             throw new Exception\ExtensionNotLoadedException("Image CAPTCHA requires GD extension");
 127         }
 128
 129         if (!function_exists("imagepng")) {
 130             throw new Exception\ExtensionNotLoadedException("Image CAPTCHA requires PNG support");
 131         }
 132
 133         if (!function_exists("imageftbbox")) {
 134             throw new Exception\ExtensionNotLoadedException("Image CAPTCHA requires FT fonts support");
 135         }
 136
 137         parent::__construct($options);
 138     }
 139
 140     /**
 141      * @return string
 142      */
 143     public function getImgAlt()
 144     {
 145         return $this->imgAlt;
 146     }
 147
 148     /**
 149      * @return string
 150      */
 151     public function getStartImage()
 152     {
 153         return $this->startImage;
 154     }
 155
 156     /**
 157      * @return int
 158      */
 159     public function getDotNoiseLevel()
 160     {
 161         return $this->dotNoiseLevel;
 162     }
 163
 164     /**
 165      * @return int
 166      */
 167     public function getLineNoiseLevel()
 168     {
 169         return $this->lineNoiseLevel;
 170     }
 171
 172     /**
 173      * Get captcha expiration
 174      *
 175      * @return int
 176      */
 177     public function getExpiration()
 178     {
 179         return $this->expiration;
 180     }
 181
 182     /**
 183      * Get garbage collection frequency
 184      *
 185      * @return int
 186      */
 187     public function getGcFreq()
 188     {
 189         return $this->gcFreq;
 190     }
 191
 192     /**
 193      * Get font to use when generating captcha
 194      *
 195      * @return string
 196      */
 197     public function getFont()
 198     {
 199         return $this->font;
 200     }
 201
 202     /**
 203      * Get font size
 204      *
 205      * @return int
 206      */
 207     public function getFontSize()
 208     {
 209         return $this->fsize;
 210     }
 211
 212     /**
 213      * Get captcha image height
 214      *
 215      * @return int
 216      */
 217     public function getHeight()
 218     {
 219         return $this->height;
 220     }
 221
 222     /**
 223      * Get captcha image directory
 224      *
 225      * @return string
 226      */
 227     public function getImgDir()
 228     {
 229         return $this->imgDir;
 230     }
 231
 232     /**
 233      * Get captcha image base URL
 234      *
 235      * @return string
 236      */
 237     public function getImgUrl()
 238     {
 239         return $this->imgUrl;
 240     }
 241
 242     /**
 243      * Get captcha image file suffix
 244      *
 245      * @return string
 246      */
 247     public function getSuffix()
 248     {
 249         return $this->suffix;
 250     }
 251
 252     /**
 253      * Get captcha image width
 254      *
 255      * @return int
 256      */
 257     public function getWidth()
 258     {
 259         return $this->width;
 260     }
 261
 262     /**
 263      * @param string $startImage
 264      * @return Image
 265      */
 266     public function setStartImage($startImage)
 267     {
 268         $this->startImage = $startImage;
 269         return $this;
 270     }
 271
 272     /**
 273      * @param int $dotNoiseLevel
 274      * @return Image
 275      */
 276     public function setDotNoiseLevel($dotNoiseLevel)
 277     {
 278         $this->dotNoiseLevel = $dotNoiseLevel;
 279         return $this;
 280     }
 281
 282     /**
 283      * @param int $lineNoiseLevel
 284      * @return Image
 285      */
 286     public function setLineNoiseLevel($lineNoiseLevel)
 287     {
 288         $this->lineNoiseLevel = $lineNoiseLevel;
 289         return $this;
 290     }
 291
 292     /**
 293      * Set captcha expiration
 294      *
 295      * @param  int $expiration
 296      * @return Image
 297      */
 298     public function setExpiration($expiration)
 299     {
 300         $this->expiration = $expiration;
 301         return $this;
 302     }
 303
 304     /**
 305      * Set garbage collection frequency
 306      *
 307      * @param  int $gcFreq
 308      * @return Image
 309      */
 310     public function setGcFreq($gcFreq)
 311     {
 312         $this->gcFreq = $gcFreq;
 313         return $this;
 314     }
 315
 316     /**
 317      * Set captcha font
 318      *
 319      * @param  string $font
 320      * @return Image
 321      */
 322     public function setFont($font)
 323     {
 324         $this->font = $font;
 325         return $this;
 326     }
 327
 328     /**
 329      * Set captcha font size
 330      *
 331      * @param  int $fsize
 332      * @return Image
 333      */
 334     public function setFontSize($fsize)
 335     {
 336         $this->fsize = $fsize;
 337         return $this;
 338     }
 339
 340     /**
 341      * Set captcha image height
 342      *
 343      * @param  int $height
 344      * @return Image
 345      */
 346     public function setHeight($height)
 347     {
 348         $this->height = $height;
 349         return $this;
 350     }
 351
 352     /**
 353      * Set captcha image storage directory
 354      *
 355      * @param  string $imgDir
 356      * @return Image
 357      */
 358     public function setImgDir($imgDir)
 359     {
 360         $this->imgDir = rtrim($imgDir, "/\\") . '/';
 361         return $this;
 362     }
 363
 364     /**
 365      * Set captcha image base URL
 366      *
 367      * @param  string $imgUrl
 368      * @return Image
 369      */
 370     public function setImgUrl($imgUrl)
 371     {
 372         $this->imgUrl = rtrim($imgUrl, "/\\") . '/';
 373         return $this;
 374     }
 375
 376     /**
 377      * @param string $imgAlt
 378      * @return Image
 379      */
 380     public function setImgAlt($imgAlt)
 381     {
 382         $this->imgAlt = $imgAlt;
 383         return $this;
 384     }
 385
 386     /**
 387      * Set captcha image filename suffix
 388      *
 389      * @param  string $suffix
 390      * @return Image
 391      */
 392     public function setSuffix($suffix)
 393     {
 394         $this->suffix = $suffix;
 395         return $this;
 396     }
 397
 398     /**
 399      * Set captcha image width
 400      *
 401      * @param  int $width
 402      * @return Image
 403      */
 404     public function setWidth($width)
 405     {
 406         $this->width = $width;
 407         return $this;
 408     }
 409
 410     /**
 411      * Generate random frequency
 412      *
 413      * @return float
 414      */
 415     protected function randomFreq()
 416     {
 417         return mt_rand(700000, 1000000) / 15000000;
 418     }
 419
 420     /**
 421      * Generate random phase
 422      *
 423      * @return float
 424      */
 425     protected function randomPhase()
 426     {
 427         // random phase from 0 to pi
 428         return mt_rand(0, 3141592) / 1000000;
 429     }
 430
 431     /**
 432      * Generate random character size
 433      *
 434      * @return int
 435      */
 436     protected function randomSize()
 437     {
 438         return mt_rand(300, 700) / 100;
 439     }
 440
 441     /**
 442      * Generate captcha
 443      *
 444      * @return string captcha ID
 445      */
 446     public function generate()
 447     {
 448         $id    = parent::generate();
 449         $tries = 5;
 450
 451         // If there's already such file, try creating a new ID
 452         while ($tries-- && file_exists($this->getImgDir() . $id . $this->getSuffix())) {
 453             $id = $this->generateRandomId();
 454             $this->setId($id);
 455         }
 456         $this->generateImage($id, $this->getWord());
 457
 458         if (mt_rand(1, $this->getGcFreq()) == 1) {
 459             $this->gc();
 460         }
 461
 462         return $id;
 463     }
 464
 465     /**
 466      * Generate image captcha
 467      *
 468      * Override this function if you want different image generator
 469      * Wave transform from http://www.captcha.ru/captchas/multiwave/
 470      *
 471      * @param string $id Captcha ID
 472      * @param string $word Captcha word
 473      * @throws Exception\NoFontProvidedException if no font was set
 474      * @throws Exception\ImageNotLoadableException if start image cannot be loaded
 475      */
 476     protected function generateImage($id, $word)
 477     {
 478         $font = $this->getFont();
 479
 480         if (empty($font)) {
 481             throw new Exception\NoFontProvidedException('Image CAPTCHA requires font');
 482         }
 483
 484         $w     = $this->getWidth();
 485         $h     = $this->getHeight();
 486         $fsize = $this->getFontSize();
 487
 488         $imgFile   = $this->getImgDir() . $id . $this->getSuffix();
 489
 490         if (empty($this->startImage)) {
 491             $img = imagecreatetruecolor($w, $h);
 492         } else {
 493             // Potential error is change to exception
 494             ErrorHandler::start();
 495             $img   = imagecreatefrompng($this->startImage);
 496             $error = ErrorHandler::stop();
 497             if (!$img || $error) {
 498                 throw new Exception\ImageNotLoadableException(
 499                     "Can not load start image '{$this->startImage}'", 0, $error
 500                 );
 501             }
 502             $w = imagesx($img);
 503             $h = imagesy($img);
 504         }
 505
 506         $textColor = imagecolorallocate($img, 0, 0, 0);
 507         $bgColor   = imagecolorallocate($img, 255, 255, 255);
 508         imagefilledrectangle($img, 0, 0, $w-1, $h-1, $bgColor);
 509         $textbox = imageftbbox($fsize, 0, $font, $word);
 510         $x = ($w - ($textbox[2] - $textbox[0])) / 2;
 511         $y = ($h - ($textbox[7] - $textbox[1])) / 2;
 512         imagefttext($img, $fsize, 0, $x, $y, $textColor, $font, $word);
 513
 514         // generate noise
 515         for ($i=0; $i < $this->dotNoiseLevel; $i++) {
 516            imagefilledellipse($img, mt_rand(0, $w), mt_rand(0, $h), 2, 2, $textColor);
 517         }
 518         for ($i=0; $i < $this->lineNoiseLevel; $i++) {
 519            imageline($img, mt_rand(0, $w), mt_rand(0, $h), mt_rand(0, $w), mt_rand(0, $h), $textColor);
 520         }
 521
 522         // transformed image
 523         $img2     = imagecreatetruecolor($w, $h);
 524         $bgColor = imagecolorallocate($img2, 255, 255, 255);
 525         imagefilledrectangle($img2, 0, 0, $w-1, $h-1, $bgColor);
 526
 527         // apply wave transforms
 528         $freq1 = $this->randomFreq();
 529         $freq2 = $this->randomFreq();
 530         $freq3 = $this->randomFreq();
 531         $freq4 = $this->randomFreq();
 532
 533         $ph1 = $this->randomPhase();
 534         $ph2 = $this->randomPhase();
 535         $ph3 = $this->randomPhase();
 536         $ph4 = $this->randomPhase();
 537
 538         $szx = $this->randomSize();
 539         $szy = $this->randomSize();
 540
 541         for ($x = 0; $x < $w; $x++) {
 542             for ($y = 0; $y < $h; $y++) {
 543                 $sx = $x + (sin($x*$freq1 + $ph1) + sin($y*$freq3 + $ph3)) * $szx;
 544                 $sy = $y + (sin($x*$freq2 + $ph2) + sin($y*$freq4 + $ph4)) * $szy;
 545
 546                 if ($sx < 0 || $sy < 0 || $sx >= $w - 1 || $sy >= $h - 1) {
 547                     continue;
 548                 } else {
 549                     $color   = (imagecolorat($img, $sx, $sy) >> 16)         & 0xFF;
 550                     $colorX  = (imagecolorat($img, $sx + 1, $sy) >> 16)     & 0xFF;
 551                     $colorY  = (imagecolorat($img, $sx, $sy + 1) >> 16)     & 0xFF;
 552                     $colorXY = (imagecolorat($img, $sx + 1, $sy + 1) >> 16) & 0xFF;
 553                 }
 554
 555                 if ($color == 255 && $colorX == 255 && $colorY == 255 && $colorXY == 255) {
 556                     // ignore background
 557                     continue;
 558                 } elseif ($color == 0 && $colorX == 0 && $colorY == 0 && $colorXY == 0) {
 559                     // transfer inside of the image as-is
 560                     $newcolor = 0;
 561                 } else {
 562                     // do antialiasing for border items
 563                     $fracX  = $sx - floor($sx);
 564                     $fracY  = $sy - floor($sy);
 565                     $fracX1 = 1 - $fracX;
 566                     $fracY1 = 1 - $fracY;
 567
 568                     $newcolor = $color   * $fracX1 * $fracY1
 569                               + $colorX  * $fracX  * $fracY1
 570                               + $colorY  * $fracX1 * $fracY
 571                               + $colorXY * $fracX  * $fracY;
 572                 }
 573
 574                 imagesetpixel($img2, $x, $y, imagecolorallocate($img2, $newcolor, $newcolor, $newcolor));
 575             }
 576         }
 577
 578         // generate noise
 579         for ($i=0; $i<$this->dotNoiseLevel; $i++) {
 580             imagefilledellipse($img2, mt_rand(0, $w), mt_rand(0, $h), 2, 2, $textColor);
 581         }
 582
 583         for ($i=0; $i<$this->lineNoiseLevel; $i++) {
 584            imageline($img2, mt_rand(0, $w), mt_rand(0, $h), mt_rand(0, $w), mt_rand(0, $h), $textColor);
 585         }
 586
 587         imagepng($img2, $imgFile);
 588         imagedestroy($img);
 589         imagedestroy($img2);
 590     }
 591
 592     /**
 593      * Remove old files from image directory
 594      *
 595      */
 596     protected function gc()
 597     {
 598         $expire = time() - $this->getExpiration();
 599         $imgdir = $this->getImgDir();
 600         if (!$imgdir || strlen($imgdir) < 2) {
 601             // safety guard
 602             return;
 603         }
 604
 605         $suffixLength = strlen($this->suffix);
 606         foreach (new DirectoryIterator($imgdir) as $file) {
 607             if (!$file->isDot() && !$file->isDir()) {
 608                 if (file_exists($file->getPathname()) && $file->getMTime() < $expire) {
 609                     // only deletes files ending with $this->suffix
 610                     if (substr($file->getFilename(), -($suffixLength)) == $this->suffix) {
 611                         unlink($file->getPathname());
 612                     }
 613                 }
 614             }
 615         }
 616     }
 617
 618     /**
 619      * Get helper name used to render captcha
 620      *
 621      * @return string
 622      */
 623     public function getHelperName()
 624     {
 625         return 'captcha/image';
 626     }
 627 }