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copied!<p>First, it's bad idea to store captcha in cookies because right captcha can be easily read from cookies by bot. Better use session or some storage instead.</p> <p>Second, there are some variables initialized in kcaptcha_config.php file, you need to move required variables initialization to your functions</p> <p>Get text function:</p> <pre><code>function make_text() { // generating random keystring while(true){ $keystring=''; for($i=0;$i<$length;$i++){ $keystring.=$allowed_symbols{mt_rand(0,strlen($allowed_symbols)-1)}; } if(!preg_match('/cp|cb|ck|c6|c9|rn|rm|mm|co|do|cl|db|qp|qb|dp|ww/', $keystring)) break; } return $keystring; } </code></pre> <p>$length and $allowed_symbols are defined in kcaptcha_config.php</p> <p>I did not check all the variables in next function, but i'm sure there will be a lot of errors.</p> <pre><code>function make_captcha($keystring){ $fonts=array(); $fontsdir_absolute=dirname(__FILE__).'/'.$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); do{ $font_file=$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; } } $img=imagecreatetruecolor($width, $height); imagealphablending($img, true); $white=imagecolorallocate($img, 255, 255, 255); $black=imagecolorallocate($img, 0, 0, 0); imagefilledrectangle($img, 0, 0, $width-1, $height-1, $white); // draw text $x=1; $odd=mt_rand(0,1); if($odd==0) $odd=-1; for($i=0;$i<$length;$i++){ $m=$font_metrics[$keystring{$i}]; $y=(($i%2)*$fluctuation_amplitude - $fluctuation_amplitude/2)*$odd + mt_rand(-round($fluctuation_amplitude/3), round($fluctuation_amplitude/3)) + ($height-$fontfile_height)/2; if($no_spaces){ $shift=0; if($i>0){ $shift=10000; for($sy=3;$sy<$fontfile_height-10;$sy+=1){ for($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>$height) break; for($px=min($left,$width-1);$px>$left-200 && $px>=0;$px-=1){ $color=imagecolorat($img, $px, $py) & 0xff; if($color+$opacity<170){ // 170 - threshold if($shift>$left-$px){ $shift=$left-$px; } break; } } break; } } } if($shift==10000){ $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; } }while($x>=$width-10); // while not fit in canvas //noise $white=imagecolorallocate($font, 255, 255, 255); $black=imagecolorallocate($font, 0, 0, 0); for($i=0;$i<(($height-30)*$x)*$white_noise_density;$i++){ imagesetpixel($img, mt_rand(0, $x-1), mt_rand(10, $height-15), $white); } for($i=0;$i<(($height-30)*$x)*$black_noise_density;$i++){ imagesetpixel($img, mt_rand(0, $x-1), mt_rand(10, $height-15), $black); } $center=$x/2; // credits. To remove, see configuration file $img2=imagecreatetruecolor($width, $height+($show_credits?12:0)); $foreground=imagecolorallocate($img2, $foreground_color[0], $foreground_color[1], $foreground_color[2]); $background=imagecolorallocate($img2, $background_color[0], $background_color[1], $background_color[2]); imagefilledrectangle($img2, 0, 0, $width-1, $height-1, $background); imagefilledrectangle($img2, 0, $height, $width-1, $height+12, $foreground); $credits=empty($credits)?$_SERVER['HTTP_HOST']:$credits; imagestring($img2, 2, $width/2-imagefontwidth(2)*strlen($credits)/2, $height-2, $credits, $background); // 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(0,31415926)/10000000; $rand6=mt_rand(0,31415926)/10000000; $rand7=mt_rand(0,31415926)/10000000; $rand8=mt_rand(0,31415926)/10000000; // amplitudes $rand9=mt_rand(330,420)/110; $rand10=mt_rand(330,450)/100; //wave distortion for($x=0;$x<$width;$x++){ for($y=0;$y<$height;$y++){ $sx=$x+(sin($x*$rand1+$rand5)+sin($y*$rand3+$rand6))*$rand9-$width/2+$center+1; $sy=$y+(sin($x*$rand2+$rand7)+sin($y*$rand4+$rand8))*$rand10; if($sx<0 || $sy<0 || $sx>=$width-1 || $sy>=$height-1){ continue; }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==255 && $color_x==255 && $color_y==255 && $color_xy==255){ continue; }else if($color==0 && $color_x==0 && $color_y==0 && $color_xy==0){ $newred=$foreground_color[0]; $newgreen=$foreground_color[1]; $newblue=$foreground_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*$foreground_color[0]+$newcolor*$background_color[0]; $newgreen=$newcolor0*$foreground_color[1]+$newcolor*$background_color[1]; $newblue=$newcolor0*$foreground_color[2]+$newcolor*$background_color[2]; } imagesetpixel($img2, $x, $y, imagecolorallocate($img2, $newred, $newgreen, $newblue)); } } header('Expires: Mon, 26 Jul 1997 05:00:00 GMT'); header('Cache-Control: no-store, no-cache, must-revalidate'); header('Cache-Control: post-check=0, pre-check=0', FALSE); header('Pragma: no-cache'); if(function_exists("imagejpeg")){ header("Content-Type: image/jpeg"); imagejpeg($img2, null, $jpeg_quality); }else if(function_exists("imagegif")){ header("Content-Type: image/gif"); imagegif($img2); }else if(function_exists("imagepng")){ header("Content-Type: image/x-png"); imagepng($img2); } } </code></pre> <p>Hope i helped you.</p>

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