/mod2/kcaptcha/includes/kcaptcha.php
PHP | 271 lines | 197 code | 43 blank | 31 comment | 49 complexity | 14efce0c5940da9a9cd8277abe5f9028 MD5 | raw file
Possible License(s): AGPL-1.0
- <?php
- # KCAPTCHA for phpBB
- # customized by dynamis based on:
- # KCAPTCHA PROJECT VERSION 1.2.4
- # Automatic test to tell computers and humans apart
- # Copyright by Kruglov Sergei, 2006
- # www.captcha.ru, www.kruglov.ru
- # System requirements: PHP 4.0.6+ w/ GD
- # KCAPTCHA is a free software. You can freely use it for building own site or software.
- # If you use this software as a part of own sofware, you must leave copyright notices intact or add KCAPTCHA copyright notices to own.
- # As a default configuration, KCAPTCHA has a small credits text at bottom of CAPTCHA image.
- # You can remove it, but I would be pleased if you left it. ;)
- class KCAPTCHA {
- var $keystring;
-
- # symbols used to draw CAPTCHA
- //var $allowed_symbols = "0123456789"; #digits
- var $allowed_symbols = "23456789abcdeghkmnpqsuvxyz"; # without similar symbols (o=0, 1=l, i=j, t=f)
- var $min_length = 5;
- var $max_length = 6;
-
- # folder with fonts
- var $fontsdir = 'fonts';
- # CAPTCHA image size
- var $width = 150;
- var $height = 60;
- # CAPTCHA image colors (RGB, 0-255)
- //var $foreground_color = array(0, 0, 0);
- //var $background_color = array(220, 230, 255);
- var $foreground_color; // set in constructor
- var $background_color; // set in constructor
-
- # symbol's vertical fluctuation amplitude divided by 2
- var $fluctuation_amplitude = 5;
- # increase safety by prevention of spaces between symbols
- var $no_spaces = true;
-
- # JPEG quality of CAPTCHA image
- var $jpeg_quality = 90;
-
-
- function getKeyString() {
- return $this->keystring;
- }
- function setKeyString($newstring = '') {
- $invalidpattern = '/cp|cb|ck|c6|c9|rn|rm|mm|mn|nm|co|do|cl|db|qp|qb|dp/';
-
- if($newstring){
- $length = strlen($newstring);
- if($length < $this->min_length || $length > $this->max_length) return false;
- for($i=0;$i<$length;$i++){
- if(strpos($this->allowed_symbols, substr($newstring, $i, 1)) === false) return false;
- }
- if(preg_match($invalidpattern, $newstring)) return false;
- $this->keystring = $newstring;
- }else {
- // generating random keystring
- $length = mt_rand($this->min_length, $this->max_length);
- while(true){
- $this->keystring='';
- for($i=0;$i<$length;$i++){
- $this->keystring.=$this->allowed_symbols{mt_rand(0,strlen($this->allowed_symbols)-1)};
- }
- if(!preg_match($invalidpattern, $this->keystring)) break;
- }
- }
- return $this->keystring;
- }
-
-
- // generates keystring and image
- function KCAPTCHA() {
- # CAPTCHA image colors (RGB, 0-255)
- $this->foreground_color = array(mt_rand(0,100), mt_rand(0,100), mt_rand(0,100));
- $this->background_color = array(mt_rand(200,255), mt_rand(200,255), mt_rand(200,255));
-
- $this->keystring = $this->setKeyString();
- }
-
-
- function genCaptcha() {
- $alphabet = "0123456789abcdefghijklmnopqrstuvwxyz"; # do not change without changing font files!
-
- $fonts=array();
- $fontsdir_absolute=dirname(__FILE__).'/'.$this->fontsdir;
- if ($handle = opendir($fontsdir_absolute)) {
- while (false !== ($file = readdir($handle))) {
- if (preg_match('/\.png$/i', $file)) {
- $fonts[]=$fontsdir_absolute.'/'.$file;
- }
- }
- closedir($handle);
- }
-
- $alphabet_length=strlen($alphabet);
-
- while(true){
- $font_file=$fonts[mt_rand(0, count($fonts)-1)];
- $font=imagecreatefrompng($font_file);
- imagealphablending($font, true);
- $fontfile_width=imagesx($font);
- $fontfile_height=imagesy($font)-1;
- $font_metrics=array();
- $symbol=0;
- $reading_symbol=false;
- // loading font
- for($i=0;$i<$fontfile_width && $symbol<$alphabet_length;$i++){
- $transparent = (imagecolorat($font, $i, 0) >> 24) == 127;
- if(!$reading_symbol && !$transparent){
- $font_metrics[$alphabet{$symbol}]=array('start'=>$i);
- $reading_symbol=true;
- continue;
- }
- if($reading_symbol && $transparent){
- $font_metrics[$alphabet{$symbol}]['end']=$i;
- $reading_symbol=false;
- $symbol++;
- continue;
- }
- }
- $img=imagecreatetruecolor($this->width, $this->height);
- imagealphablending($img, true);
- $white=imagecolorallocate($img, 255, 255, 255);
- $black=imagecolorallocate($img, 0, 0, 0);
- imagefilledrectangle($img, 0, 0, $this->width-1, $this->height-1, $white);
- // draw text
- $x=1;
- $length = strlen($this->keystring);
- for($i=0;$i<$length;$i++){
- $m=$font_metrics[$this->keystring{$i}];
- $y=mt_rand(-$this->fluctuation_amplitude, $this->fluctuation_amplitude)+($this->height-$fontfile_height)/2+2;
- if($this->no_spaces){
- $shift=0;
- if($i>0){
- $shift=1000;
- for($sy=7;$sy<$fontfile_height-20;$sy+=1){
- //for($sx=$m['start']-1;$sx<$m['end'];$sx+=1){
- for($sx=$m['start']-1;$sx<$m['end'];$sx+=1){
- $rgb=imagecolorat($font, $sx, $sy);
- $opacity=$rgb>>24;
- if($opacity<127){
- $left=$sx-$m['start']+$x;
- $py=$sy+$y;
- if($py>$this->height) break;
- for($px=min($left,$this->width-1);$px>$left-12 && $px>=0;$px-=1){
- $color=imagecolorat($img, $px, $py) & 0xff;
- if($color+$opacity<190){
- if($shift>$left-$px){
- $shift=$left-$px;
- }
- break;
- }
- }
- break;
- }
- }
- }
- if($shift==1000){
- $shift=mt_rand(4,6);
- }
- }
- }else{
- $shift=1;
- }
- imagecopy($img,$font,$x-$shift,$y,$m['start'],1,$m['end']-$m['start'],$fontfile_height);
- $x+=$m['end']-$m['start']-$shift;
- }
- if($x<$this->width-10) break; // fit in canvas
-
- }
- $center=$x/2;
- $img2=imagecreatetruecolor($this->width, $this->height);
- $foreground=imagecolorallocate($img2, $this->foreground_color[0], $this->foreground_color[1], $this->foreground_color[2]);
- $background=imagecolorallocate($img2, $this->background_color[0], $this->background_color[1], $this->background_color[2]);
- // periods
- $rand1=mt_rand(750000,1200000)/10000000;
- $rand2=mt_rand(750000,1200000)/10000000;
- $rand3=mt_rand(750000,1200000)/10000000;
- $rand4=mt_rand(750000,1200000)/10000000;
- // phases
- $rand5=mt_rand(0,3141592)/500000;
- $rand6=mt_rand(0,3141592)/500000;
- $rand7=mt_rand(0,3141592)/500000;
- $rand8=mt_rand(0,3141592)/500000;
- // amplitudes
- $rand9=mt_rand(330,420)/110;
- $rand10=mt_rand(330,450)/110;
- //wave distortion
- for($x=0;$x<$this->width;$x++){
- for($y=0;$y<$this->height;$y++){
- $sx=$x+(sin($x*$rand1+$rand5)+sin($y*$rand3+$rand6))*$rand9-$this->width/2+$center+1;
- $sy=$y+(sin($x*$rand2+$rand7)+sin($y*$rand4+$rand8))*$rand10;
- if($sx<0 || $sy<0 || $sx>=$this->width-1 || $sy>=$this->height-1){
- $color=255;
- $color_x=255;
- $color_y=255;
- $color_xy=255;
- }else{
- $color=imagecolorat($img, $sx, $sy) & 0xFF;
- $color_x=imagecolorat($img, $sx+1, $sy) & 0xFF;
- $color_y=imagecolorat($img, $sx, $sy+1) & 0xFF;
- $color_xy=imagecolorat($img, $sx+1, $sy+1) & 0xFF;
- }
- if($color==0 && $color_x==0 && $color_y==0 && $color_xy==0){
- $newred=$this->foreground_color[0];
- $newgreen=$this->foreground_color[1];
- $newblue=$this->foreground_color[2];
- }else if($color==255 && $color_x==255 && $color_y==255 && $color_xy==255){
- $newred=$this->background_color[0];
- $newgreen=$this->background_color[1];
- $newblue=$this->background_color[2];
- }else{
- $frsx=$sx-floor($sx);
- $frsy=$sy-floor($sy);
- $frsx1=1-$frsx;
- $frsy1=1-$frsy;
- $newcolor=(
- $color*$frsx1*$frsy1+
- $color_x*$frsx*$frsy1+
- $color_y*$frsx1*$frsy+
- $color_xy*$frsx*$frsy);
- if($newcolor>255) $newcolor=255;
- $newcolor=$newcolor/255;
- $newcolor0=1-$newcolor;
- $newred=$newcolor0*$this->foreground_color[0]+$newcolor*$this->background_color[0];
- $newgreen=$newcolor0*$this->foreground_color[1]+$newcolor*$this->background_color[1];
- $newblue=$newcolor0*$this->foreground_color[2]+$newcolor*$this->background_color[2];
- }
- imagesetpixel($img2, $x, $y, imagecolorallocate($img2, $newred, $newgreen, $newblue));
- }
- }
- if(function_exists("imagepng")){
- header("Content-Type: image/x-png");
- imagepng($img2);
- }else if(function_exists("imagejpeg")){
- header("Content-Type: image/jpeg");
- imagejpeg($img2, null, $this->jpeg_quality);
- }else if(function_exists("imagegif")){
- header("Content-Type: image/gif");
- imagegif($img2);
- }
- }
- }
- ?>