/ php-ppcms/includes/classes/lib.captcha.class.php

<?php

/***************************************************************

*  Copyright notice

*  (c) 2009, jianyuzhu@gmail.com

*  All rights reserved

*  This script is part of the PPEMI project.

***************************************************************/



/**

 * LibCaptcha class

 *

 */

class LibCaptcha {

	/** Text */

	var $text = '';



    /** Width of the image */

    var $width  = 200;



    /** Height of the image */

    var $height = 70;



    /** Dictionary word file (empty for randnom text) */

    var $wordsFile = 'words/en.php';



    /**

     * Path for resource files (fonts, words, etc.)

     *

     * "resources" by default. For security reasons, is better move this

     * directory to another location outise the web server

     *

     */

    var $resourcesPath = 'resources';



    /** Min word length (for non-dictionary random text generation) */

    var $minWordLength = 5;



    /**

     * Max word length (for non-dictionary random text generation)

     * 

     * Used for dictionary words indicating the word-length

     * for font-size modification purposes

     */

    var $maxWordLength = 8;



    /** Sessionname to store the original text */

    var $session_var = 'captcha';



    /** Background color in RGB-array */

    var $backgroundColor = array(255, 255, 255);



    /** Foreground colors in RGB-array */

    var $colors = array(

        array(27,78,181), // blue

        array(22,163,35), // green

        array(214,36,7),  // red

    );



    /** Shadow color in RGB-array or null */

    var $shadowColor = null; //array(0, 0, 0);



    /**

     * Font configuration

     *

     * - font: TTF file

     * - spacing: relative pixel space between character

     * - minSize: min font size

     * - maxSize: max font size

     */

    var $fonts = array(

        'Antykwa'  => array('spacing' => -3, 'minSize' => 27, 'maxSize' => 30, 'font' => 'AntykwaBold.ttf'),

        'Candice'  => array('spacing' =>-1.5,'minSize' => 28, 'maxSize' => 31, 'font' => 'Candice.ttf'),

        'DingDong' => array('spacing' => -2, 'minSize' => 24, 'maxSize' => 30, 'font' => 'Ding-DongDaddyO.ttf'),

        'Duality'  => array('spacing' => -2, 'minSize' => 30, 'maxSize' => 38, 'font' => 'Duality.ttf'),

        'Heineken' => array('spacing' => -2, 'minSize' => 24, 'maxSize' => 34, 'font' => 'Heineken.ttf'),

        'Jura'     => array('spacing' => -2, 'minSize' => 28, 'maxSize' => 32, 'font' => 'Jura.ttf'),

        'StayPuft' => array('spacing' =>-1.5,'minSize' => 28, 'maxSize' => 32, 'font' => 'StayPuft.ttf'),

        'Times'    => array('spacing' => -2, 'minSize' => 28, 'maxSize' => 34, 'font' => 'TimesNewRomanBold.ttf'),

        'VeraSans' => array('spacing' => -1, 'minSize' => 20, 'maxSize' => 28, 'font' => 'VeraSansBold.ttf'),

    );



    /** Wave configuracion in X and Y axes */

    var $Yperiod    = 12;

    var $Yamplitude = 14;

    var $Xperiod    = 11;

    var $Xamplitude = 5;



    /** letter rotation clockwise */

    var $maxRotation = 8;



    /**

     * Internal image size factor (for better image quality)

     * 1: low, 2: medium, 3: high

     */

    var $scale = 2;



    /** 

     * Blur effect for better image quality (but slower image processing).

     * Better image results with scale=3

     */

    var $blur = false;



    /** Debug? */

    var $debug = false;

    

    /** Image format: jpeg or png */

    var $imageFormat = 'jpeg';

	

    /** GD image */

    var $im;

	

	//constructor

    function CreateImage() {

        $ini = microtime(true);



        /** Initialization */

        $this->ImageAllocate();

        

        /** Text insertion */

        $text = $this->GetCaptchaText();

        $fontcfg  = $this->fonts[array_rand($this->fonts)];

        $this->WriteText($text, $fontcfg);



        $_SESSION[$this->session_var] = $text;



        /** Transformations */

        $this->WaveImage();

        if ($this->blur && function_exists('imagefilter')) {

            imagefilter($this->im, IMG_FILTER_GAUSSIAN_BLUR);

        }

        $this->ReduceImage();





        if ($this->debug) {

            imagestring($this->im, 1, 1, $this->height-8,

                "$text {$fontcfg['font']} ".round((microtime(true)-$ini)*1000)."ms",

                $this->GdFgColor

            );

        }





        /** Output */

        $this->WriteImage();

        $this->Cleanup();

    }

    /**

     * Creates the image resources

     */

    function ImageAllocate() {

        // Cleanup

        if (!empty($this->im)) {

            imagedestroy($this->im);

        }



        $this->im = imagecreatetruecolor($this->width*$this->scale, $this->height*$this->scale);



        // Background color

        $this->GdBgColor = imagecolorallocate($this->im,

            $this->backgroundColor[0],

            $this->backgroundColor[1],

            $this->backgroundColor[2]

        );

        imagefilledrectangle($this->im, 0, 0, $this->width*$this->scale, $this->height*$this->scale, $this->GdBgColor);



        // Foreground color

        $color           = $this->colors[mt_rand(0, sizeof($this->colors)-1)];

        $this->GdFgColor = imagecolorallocate($this->im, $color[0], $color[1], $color[2]);



        // Shadow color

        if (!empty($this->shadowColor) && is_array($this->shadowColor) && sizeof($this->shadowColor) >= 3) {

            $this->GdShadowColor = imagecolorallocate($this->im,

                $this->shadowColor[0],

                $this->shadowColor[1],

                $this->shadowColor[2]

            );

        }

    }

    /**

     * Text generation

     *

     * @return string Text

     */

    function GetCaptchaText() {

		if( $this->text != '' ) {

			return $this->text;

		}

        $text = $this->GetDictionaryCaptchaText();

        if (!$text) {

            $text = $this->GetRandomCaptchaText();

        }

        return $text;

    }

    /**

     * Random text generation

     *

     * @return string Text

     */

    function GetRandomCaptchaText($length = null) {

        if (empty($length)) {

            $length = rand($this->minWordLength, $this->maxWordLength);

        }



        $words  = "abcdefghijlmnopqrstvwyz";

        $vocals = "aeiou";



        $text  = "";

        $vocal = rand(0, 1);

        for ($i=0; $i<$length; $i++) {

            if ($vocal) {

                $text .= substr($vocals, mt_rand(0, 4), 1);

            } else {

                $text .= substr($words, mt_rand(0, 22), 1);

            }

            $vocal = !$vocal;

        }

        return $text;

    }

    /**

     * Random dictionary word generation

     *

     * @param boolean $extended Add extended "fake" words

     * @return string Word

     */

    function GetDictionaryCaptchaText($extended = false) {

        if (empty($this->wordsFile)) {

            return false;

        }



        // Full path of words file

        if (substr($this->wordsFile, 0, 1) == '/') {

            $wordsfile = $this->wordsFile;

        } else {

            $wordsfile = $this->resourcesPath.'/'.$this->wordsFile;

        }



        $fp     = fopen($wordsfile, "r");

        $length = strlen(fgets($fp));

        if (!$length) {

            return false;

        }

        $line   = rand(1, (filesize($wordsfile)/$length)-2);

        if (fseek($fp, $length*$line) == -1) {

            return false;

        }

        $text = trim(fgets($fp));

        fclose($fp);





        /** Change ramdom volcals */

        if ($extended) {

            $text   = preg_split('//', $text, -1, PREG_SPLIT_NO_EMPTY);

            $vocals = array('a', 'e', 'i', 'o', 'u');

            foreach($text as $i => $char) {

                if (mt_rand(0, 1) && in_array($char, $vocals)) {

                    $text[$i] = $vocals[mt_rand(0, 4)];

                }

            }

            $text = implode('', $text);

        }



        return $text;

    }

    /**

     * Text insertion

     */

    function WriteText($text, $fontcfg = array()) {

        if (empty($fontcfg)) {

            // Select the font configuration

            $fontcfg  = $this->fonts[array_rand($this->fonts)];

        }



        // Full path of font file

        $fontfile = $this->resourcesPath.'/fonts/'.$fontcfg['font'];





        /** Increase font-size for shortest words: 9% for each glyp missing */

        $lettersMissing = $this->maxWordLength-strlen($text);

        $fontSizefactor = 1+($lettersMissing*0.09);



        // Text generation (char by char)

        $x      = 20*$this->scale;

        $y      = round(($this->height*27/40)*$this->scale);

        $length = strlen($text);

        for ($i=0; $i<$length; $i++) {

            $degree   = rand($this->maxRotation*-1, $this->maxRotation);

            $fontsize = rand($fontcfg['minSize'], $fontcfg['maxSize'])*$this->scale*$fontSizefactor;

            $letter   = substr($text, $i, 1);



            if ($this->shadowColor) {

                $coords = imagettftext($this->im, $fontsize, $degree,

                    $x+$this->scale, $y+$this->scale,

                    $this->GdShadowColor, $fontfile, $letter);

            }

            $coords = imagettftext($this->im, $fontsize, $degree,

                $x, $y,

                $this->GdFgColor, $fontfile, $letter);

            $x += ($coords[2]-$x) + ($fontcfg['spacing']*$this->scale);

        }

    }

    /**

     * Wave filter

     */

    function WaveImage() {

        // X-axis wave generation

        $xp = $this->scale*$this->Xperiod*rand(1,3);

        $k = rand(0, 100);

        for ($i = 0; $i < ($this->width*$this->scale); $i++) {

            imagecopy($this->im, $this->im,

                $i-1, sin($k+$i/$xp) * ($this->scale*$this->Xamplitude),

                $i, 0, 1, $this->height*$this->scale);

        }



        // Y-axis wave generation

        $k = rand(0, 100);

        $yp = $this->scale*$this->Yperiod*rand(1,2);

        for ($i = 0; $i < ($this->height*$this->scale); $i++) {

            imagecopy($this->im, $this->im,

                sin($k+$i/$yp) * ($this->scale*$this->Yamplitude), $i-1,

                0, $i, $this->width*$this->scale, 1);

        }

    }

    /**

     * Reduce the image to the final size

     */

    function ReduceImage() {

        // Reduzco el tama?o de la imagen

        $imResampled = imagecreatetruecolor($this->width, $this->height);

        imagecopyresampled($imResampled, $this->im,

            0, 0, 0, 0,

            $this->width, $this->height,

            $this->width*$this->scale, $this->height*$this->scale

        );

        imagedestroy($this->im);

        $this->im = $imResampled;

    }

    /**

     * File generation

     */

    function WriteImage() {

        if ($this->imageFormat == 'png' && function_exists('imagepng')) {

            header("Content-type: image/png");

            imagepng($this->im);

        } else {

            header("Content-type: image/jpeg");

            imagejpeg($this->im, null, 80);

        }

    }

    /**

     * Cleanup

     */

    function Cleanup() {

        imagedestroy($this->im);

    }

}

//

?>