Securimage Class Reference

Collaboration diagram for Securimage:

Public Member Functions
	__construct ()
	Class constructor.
	addSignature ()
	Print signature text on image.
	allocateColors ()
	Allocate all colors that will be used in the CAPTCHA image.
	check ($code)
	Validate the code entered by the user.
	checkCode ()
	Check if the user entered code was correct.
	clearCodeFromDatabase ()
	Delete a code from the database by ip address hash.
	createCode ()
	Create a code and save to the session.
	distortedCopy ()
	Warp text from temporary image onto final image.
	doImage ()
	Generate and output the image.
	drawLines ()
	Draw random curvy lines over the image Modified code from HKCaptcha.
	drawWord ()
	Draw the CAPTCHA code over the image.
	frand ()
	Generate random number less than 1.
	generateCode ($len)
	Generate a code.
	generateMP3 ($letters)
	Generate an mp3 file by concatenating individual files.
	generateWAV ($letters)
	Generate a wav file by concatenating individual files.
	getAudibleCode ($format='wav')
	Get WAV or MP3 file data of the spoken code.
	getBackgroundFromDirectory ()
	Return the full path to a random gif, jpg, or png from the background directory.
	getCode ()
	Get the captcha code.
	getCodeFromDatabase ()
	Get stored captcha code from sqlite database based on ip address hash.
	getIPHash ()
	Get hashed IP address of remote user.
	isCodeExpired ($creation_time)
	Check a code to see if it is expired based on creation time.
	openDatabase ()
	Open SQLite database.
	output ()
	Output image to the browser.
	outputAudioFile ()
	Output audio file with HTTP headers to browser.
	purgeOldCodesFromDatabase ()
	Purge codes over a day old from database.
	readCodeFromFile ()
	Reads a word list file to get a code.
	saveCodeToDatabase ()
	Save captcha code to sqlite database.
	saveData ()
	Save the code in the session.
	scrambleAudioData (&$data, $format)
	Randomly modify the audio data to scramble sound and prevent binary recognition.
	setAudioPath ($audio_directory)
	Set the path to the audio directory.
	setBackground ()
	Set the background of the CAPTCHA image.
	show ($background_image="")
	Generate a code and output the image to the browser.
	validate ()
	Validate the code to the user code.

Data Fields
	$audio_format
	$audio_path
	$background_directory = null
	$bgimg
	$charset
	$code
	$code_entered
	$code_length
	$correct_code
	$draw_lines_over_text
	$expiry_time
	$gd_font_file
	$gd_font_size
	$gdbgcolor
	$gdlinecolor
	$gdmulticolor
	$gdsignaturecolor
	$gdtextcolor
	$im
	$image_bg_color
	$image_height
	$image_signature
	$image_type
	$image_width
	$iscale
	$line_color
	$multi_text_color
	$num_lines
	$perturbation
	$session_name = ''
	$signature_color
	$signature_font
	$sqlite_database
	$sqlite_handle
	$text_angle_maximum
	$text_angle_minimum
	$text_color
	$text_transparency_percentage
	$text_x_start
	$tmpimg
	$ttf_file
	$use_gd_font
	$use_multi_text
	$use_sqlite_db
	Use an SQLite database for storing codes as a backup to sessions.
	$use_transparent_text
	$use_wordlist = false
	$wordlist_file

Detailed Description

Definition at line 107 of file securimage.php.

Constructor & Destructor Documentation

__construct()

Securimage::__construct

(

)

Class constructor.

Because the class uses sessions, this will attempt to start a session if there is no previous one.
If you do not start a session before calling the class, the constructor must be called before any output is sent to the browser.

$securimage = new Securimage();

Definition at line 507 of file securimage.php.

        {
                // Initialize session or attach to existing
                if ( session_id() == '' ) { // no session has been started yet, which is needed for validation
                        if (trim($this->session_name) != '') {
                                session_name($this->session_name); // set session name if provided
                        }
                        session_start();
                }
 
                // Set Default Values
                $this->image_width   = 230;
                $this->image_height  = 80;
                $this->image_type    = SI_IMAGE_PNG;
 
                $this->code_length   = 6;
                $this->charset       = 'ABCDEFGHKLMNPRSTUVWYZabcdefghklmnprstuvwyz23456789';
                $this->wordlist_file = './words/words.txt';
                $this->use_wordlist  = false;
 
                $this->gd_font_file  = 'gdfonts/automatic.gdf';
                $this->use_gd_font   = false;
                $this->gd_font_size  = 24;
                $this->text_x_start  = 15;
 
                $this->ttf_file      = './AHGBold.ttf';
 
                $this->perturbation       = 0.75;
                $this->iscale             = 5;
                $this->text_angle_minimum = 0;
                $this->text_angle_maximum = 0;
 
                $this->image_bg_color   = new Securimage_Color(0xff, 0xff, 0xff);
    $this->text_color       = new Securimage_Color(0x3d, 0x3d, 0x3d);
                $this->multi_text_color = array(new Securimage_Color(0x0, 0x20, 0xCC),
                                                new Securimage_Color(0x0, 0x30, 0xEE),
                                                new Securimage_color(0x0, 0x40, 0xCC),
                                                new Securimage_Color(0x0, 0x50, 0xEE),
                                                new Securimage_Color(0x0, 0x60, 0xCC));
                $this->use_multi_text   = false;
 
                $this->use_transparent_text         = false;
                $this->text_transparency_percentage = 30;
 
                $this->num_lines            = 10;
                $this->line_color           = new Securimage_Color(0x3d, 0x3d, 0x3d);
                $this->draw_lines_over_text = true;
 
                $this->image_signature = '';
                $this->signature_color = new Securimage_Color(0x20, 0x50, 0xCC);
                $this->signature_font  = './AHGBold.ttf';
 
                $this->audio_path   = './audio/';
                $this->audio_format = 'mp3';
                $this->session_name = '';
                $this->expiry_time  = 900;
                
                $this->sqlite_database = 'database/securimage.sqlite';
                $this->use_sqlite_db   = false;
                
                $this->sqlite_handle = false;
        }

References audio_format, code_length, image_bg_color, image_height, image_signature, image_type, image_width, line_color, multi_text_color, num_lines, perturbation, signature_color, text_angle_maximum, text_angle_minimum, text_color, text_transparency_percentage, use_multi_text, use_transparent_text, and use_wordlist.

Member Function Documentation

addSignature()

Securimage::addSignature

(

)

Print signature text on image.

Since

2.0 @access private

Definition at line 1379 of file securimage.php.

        {
                if ($this->use_gd_font) {
                        imagestring($this->im, 5, $this->image_width - (strlen($this->image_signature) * 10), $this->image_height - 20, $this->image_signature, $this->gdsignaturecolor);
                } else {
                         
                        $bbox = imagettfbbox(10, 0, $this->signature_font, $this->image_signature);
                        $textlen = $bbox[2] - $bbox[0];
                        $x = $this->image_width - $textlen - 5;
                        $y = $this->image_height - 3;
                         
                        imagettftext($this->im, 10, 0, $x, $y, $this->gdsignaturecolor, $this->signature_font, $this->image_signature);
                }
        }

References $x, image_height, image_signature, and image_width.

Referenced by doImage().

allocateColors()

Securimage::allocateColors

(

)

Allocate all colors that will be used in the CAPTCHA image.

Since

2.0.1 @access private

Definition at line 693 of file securimage.php.

        {
                // allocate bg color first for imagecreate
                $this->gdbgcolor = imagecolorallocate($this->im, $this->image_bg_color->r??0, $this->image_bg_color->g??0, $this->image_bg_color->b??0);
 
        $this->text_color->r=$this->text_color->r??rand(0,255);
        $this->text_color->g=$this->text_color->g??rand(0,255);
        $this->text_color->b=$this->text_color->b??rand(0,255);
        $this->line_color->r=$this->line_color->r??rand(0,255);
        $this->line_color->g=$this->line_color->g??rand(0,255);
        $this->line_color->b=$this->line_color->b??rand(0,255);
 
 
 
                $alpha = intval($this->text_transparency_percentage / 100 * 127);
                
                if ($this->use_transparent_text == true) {
          $this->gdtextcolor = imagecolorallocatealpha($this->im, $this->text_color->r, $this->text_color->g, $this->text_color->b, $alpha);
          $this->gdlinecolor = imagecolorallocatealpha($this->im, $this->line_color->r, $this->line_color->g, $this->line_color->b, $alpha);
                } elseif ( $this->text_color != null ) {
                        $this->gdtextcolor = imagecolorallocate($this->im, $this->text_color->r, $this->text_color->g, $this->text_color->b);
            $this->gdlinecolor = imagecolorallocate($this->im, $this->line_color->r, $this->line_color->g, $this->line_color->b);
                } else {
            $red=rand(0,255);
            $green=rand(0,255);
            $blue=rand(0,255);
            $this->gdtextcolor = imagecolorallocate($this->im, $red, $green,$blue);
            $this->gdlinecolor = imagecolorallocate($this->im, $red, $green, $blue);
        }
    
    $this->gdsignaturecolor = imagecolorallocate($this->im, $this->signature_color->r??0, $this->signature_color->g??0, $this->signature_color->b??0);
    
    if ($this->use_multi_text == true) {
        $this->gdmulticolor = array();
        
        foreach($this->multi_text_color??[] as $color) {
            $color->r=$color->r??rand(0,255);
            $color->g= $color->g??rand(0,255);
            $color->b=$color->b??rand(0,255);
                if ($this->use_transparent_text == true) {
                  $this->gdmulticolor[] = imagecolorallocatealpha($this->im, $color->r, $color->g, $color->b, $alpha);
                } else {
                        $this->gdmulticolor[] = imagecolorallocate($this->im, $color->r, $color->g, $color->b);
                }
        }
    }
        }

References $color, elseif, image_bg_color, line_color, multi_text_color, signature_color, text_color, text_transparency_percentage, use_multi_text, and use_transparent_text.

Referenced by doImage().

check()

Securimage::check

(

$code

)

Validate the code entered by the user.

$code = $_POST['code']; if ($securimage->check($code) == false) { die("Sorry, the code entered did not match."); } else { $valid = true; }

Parameters

string

$code

The code the user entered

Returns

boolean true if the code was correct, false if not

Definition at line 606 of file securimage.php.

        {
                $this->code_entered = $code;
                $this->validate();
                return $this->correct_code;
        }

References $code, and validate().

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checkCode()

Securimage::checkCode

(

)

Check if the user entered code was correct.

@access private

Returns

boolean

Definition at line 1218 of file securimage.php.

        {
                return $this->correct_code;
        }

clearCodeFromDatabase()

Securimage::clearCodeFromDatabase

(

)

Delete a code from the database by ip address hash.

@access private

Since

2.0.1

Definition at line 1489 of file securimage.php.

        {
                if ($this->sqlite_handle !== false) {
                        $ip = $this->getIPHash();
                        
                        sqlite_query($this->sqlite_handle, "DELETE FROM codes WHERE iphash = '$ip'");
                }
        }

References getIPHash().

Referenced by validate().

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createCode()

Securimage::createCode

(

)

Create a code and save to the session.

@access private

Since

1.0.1

Definition at line 999 of file securimage.php.

        {
                $this->code = false;
 
                if ($this->use_wordlist && is_readable($this->wordlist_file)) {
                        $this->code = $this->readCodeFromFile();
                }
 
                if ($this->code == false) {
                        $this->code = $this->generateCode($this->code_length);
                }
                
                $this->saveData();
        }

References code_length, generateCode(), readCodeFromFile(), saveData(), and use_wordlist.

Referenced by doImage(), and getAudibleCode().

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distortedCopy()

Securimage::distortedCopy

(

)

Warp text from temporary image onto final image.

Modified for securimage

@access private

Since

2.0

Author

Han-Kwang Nienhuys modified

Copyright

Han-Kwang Neinhuys

Definition at line 939 of file securimage.php.

        {
                $numpoles = 3; // distortion factor
                 
                // make array of poles AKA attractor points
                for ($i = 0; $i < $numpoles; ++$i) {
                        $px[$i]  = rand((int) ($this->image_width * 0.3), (int)( $this->image_width * 0.7));
                        $py[$i]  = rand((int) ($this->image_height * 0.3),(int) ($this->image_height * 0.7));
                        $rad[$i] = rand((int) ($this->image_width * 0.4), (int) ($this->image_width * 0.7));
                        $tmp     = -$this->frand() * 0.15 - 0.15;
                        $amp[$i] = $this->perturbation * $tmp;
                }
                 
                $bgCol   = imagecolorat($this->tmpimg, 0, 0);
                $width2  = $this->iscale * $this->image_width;
                $height2 = $this->iscale * $this->image_height;
                 
                imagepalettecopy($this->im, $this->tmpimg); // copy palette to final image so text colors come across
                 
                // loop over $img pixels, take pixels from $tmpimg with distortion field
                for ($ix = 0; $ix < $this->image_width; ++$ix) {
                        for ($iy = 0; $iy < $this->image_height; ++$iy) {
                                $x = $ix;
                                $y = $iy;
                                        
                                for ($i = 0; $i < $numpoles; ++$i) {
                                        $dx = $ix - $px[$i];
                                        $dy = $iy - $py[$i];
                                        if ($dx == 0 && $dy == 0) continue;
 
                                        $r = sqrt($dx * $dx + $dy * $dy);
                                        if ($r > $rad[$i]) continue;
 
                                        $rscale = $amp[$i] * sin(3.14 * $r / $rad[$i]);
                                        $x += $dx * $rscale;
                                        $y += $dy * $rscale;
                                }
                                        
                                $c = $bgCol;
                                $x *= $this->iscale;
                                $y *= $this->iscale;
 
                                if ($x >= 0 && $x < $width2 && $y >= 0 && $y < $height2) {
                                        $c = imagecolorat($this->tmpimg, (int) $x,(int) $y);
                                }
 
                                if ($c != $bgCol) { // only copy pixels of letters to preserve any background image
                                        imagesetpixel($this->im, $ix, $iy, $c);
                                }
                        }
                }
        }

References $c, $i, $ix, $r, $rad, $tmp, $x, frand(), image_height, image_width, and perturbation.

Referenced by doImage().

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doImage()

Securimage::doImage

(

)

Generate and output the image.

@access private

Definition at line 653 of file securimage.php.

        {
                if ($this->use_gd_font == true || $this->iscale == null || $this->iscale == 0) {
                        $this->iscale = 1;
                }
                if($this->use_transparent_text == true || $this->bgimg != "") {
                        $this->im     = imagecreatetruecolor($this->image_width, $this->image_height);
                        $this->tmpimg = imagecreatetruecolor($this->image_width * $this->iscale, $this->image_height * $this->iscale);
 
                } else { //no transparency
                        $this->im     = imagecreate($this->image_width, $this->image_height);
                        $this->tmpimg = imagecreate($this->image_width * $this->iscale, $this->image_height * $this->iscale);
                }
                
                $this->allocateColors();
                imagepalettecopy($this->tmpimg, $this->im);
 
                $this->setBackground();
 
                $this->createCode();
 
                if (!$this->draw_lines_over_text && $this->num_lines > 0) $this->drawLines();
 
                $this->drawWord();
                if ($this->use_gd_font == false && is_readable($this->ttf_file)) $this->distortedCopy();
 
                if ($this->draw_lines_over_text && $this->num_lines > 0) $this->drawLines();
 
                if (trim($this->image_signature) != '')  $this->addSignature();
 
                $this->output();
 
        }

References addSignature(), allocateColors(), bgimg, createCode(), distortedCopy(), drawLines(), drawWord(), image_height, image_signature, image_width, num_lines, output(), setBackground(), and use_transparent_text.

Referenced by show().

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drawLines()

Securimage::drawLines

(

)

Draw random curvy lines over the image
Modified code from HKCaptcha.

Since

2.0 @access private

Definition at line 814 of file securimage.php.

        {
                for ($line = 0; $line < $this->num_lines; ++$line) {
                        $x = $this->image_width * (1 + $line) / ($this->num_lines + 1);
                        $x += (0.5 - $this->frand()) * $this->image_width / $this->num_lines;
                        $y = rand($this->image_height * 0.1, $this->image_height * 0.9);
                         
                        $theta = ($this->frand()-0.5) * M_PI * 0.7;
                        $w = $this->image_width;
                        $len = rand($w * 0.4, $w * 0.7);
                        $lwid = rand(0, 2);
                         
                        $k = $this->frand() * 0.6 + 0.2;
                        $k = $k * $k * 0.5;
                        $phi = $this->frand() * 6.28;
                        $step = 0.5;
                        $dx = $step * cos($theta);
                        $dy = $step * sin($theta);
                        $n = $len / $step;
                        $amp = 1.5 * $this->frand() / ($k + 5.0 / $len);
                        $x0 = $x - 0.5 * $len * cos($theta);
                        $y0 = $y - 0.5 * $len * sin($theta);
                         
                        $ldx = round(-$dy * $lwid);
                        $ldy = round($dx * $lwid);
                         
                        for ($i = 0; $i < $n; ++$i) {
                                $x = $x0 + $i * $dx + $amp * $dy * sin($k * $i * $step + $phi);
                                $y = $y0 + $i * $dy - $amp * $dx * sin($k * $i * $step + $phi);
                                $x=(int) $x;
                                $y=(int) $y;
                                imagefilledrectangle($this->im, $x, $y, $x + $lwid, $y + $lwid, $this->gdlinecolor);
                        }
                }
        }

References $i, $line, $n, $step, $w, $x, frand(), image_height, and image_width.

Referenced by doImage().

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drawWord()

Securimage::drawWord

(

)

Draw the CAPTCHA code over the image.

@access private

Definition at line 856 of file securimage.php.

        {
                $width2 = $this->image_width * $this->iscale;
                $height2 = $this->image_height * $this->iscale;
                 
                if ($this->use_gd_font == true || !is_readable($this->ttf_file??"")) {
                        if (!is_int($this->gd_font_file)) { //is a file name
                                $font = @imageloadfont($this->gd_font_file??"");
                                if ($font == false) {
                                        trigger_error("Failed to load GD Font file {$this->gd_font_file} ", E_USER_WARNING);
                                        return;
                                }
                        } else { //gd font identifier
                                $font = $this->gd_font_file;
                        }
 
                        imagestring($this->im, $font, $this->text_x_start, ($this->image_height / 2) - ($this->gd_font_size / 2), $this->code, $this->gdtextcolor);
                } else { //ttf font
                        $font_size = $height2 * .35;
                        $bb = imagettfbbox($font_size, 0, $this->ttf_file, $this->code);
                        $tx = $bb[4] - $bb[0];
                        $ty = $bb[5] - $bb[1];
                        $x  = floor($width2 / 2 - $tx / 2 - $bb[0]);
                        $y  = round($height2 / 2 - $ty / 2 - $bb[1]);
 
                        $strlen = strlen($this->code);
                        if (!is_array($this->multi_text_color)) $this->use_multi_text = false;
 
 
                        if ($this->use_multi_text == false && $this->text_angle_minimum == 0 && $this->text_angle_maximum == 0) { // no angled or multi-color characters
                                imagettftext($this->tmpimg, $font_size, 0, $x, $y, $this->gdtextcolor, $this->ttf_file, $this->code);
                        } else {
                                for($i = 0; $i < $strlen; ++$i) {
                                        $angle = rand($this->text_angle_minimum, $this->text_angle_maximum);
                                        $y = rand($y - 5, $y + 5);
                                        if ($this->use_multi_text == true) {
                                                $font_color = $this->gdmulticolor[rand(0, sizeof($this->gdmulticolor) - 1)];
                                        } else {
                                                $font_color = $this->gdtextcolor;
                                        }
                                        
                                        $ch = $this->code[$i];
                                         
                                        imagettftext($this->tmpimg, $font_size, $angle, $x, $y, $font_color, $this->ttf_file, $ch);
                                         
                                        // estimate character widths to increment $x without creating spaces that are too large or too small
                                        // these are best estimates to align text but may vary between fonts
                                        // for optimal character widths, do not use multiple text colors or character angles and the complete string will be written by imagettftext
                                        if (strpos('abcdeghknopqsuvxyz', $ch) !== false) {
                                                $min_x = $font_size - ($this->iscale * 6);
                                                $max_x = $font_size - ($this->iscale * 6);
                                        } else if (strpos('ilI1', $ch) !== false) {
                                                $min_x = $font_size / 5;
                                                $max_x = $font_size / 3;
                                        } else if (strpos('fjrt', $ch) !== false) {
                                                $min_x = $font_size - ($this->iscale * 12);
                                                $max_x = $font_size - ($this->iscale * 12);
                                        } else if ($ch == 'wm') {
                                                $min_x = $font_size;
                                                $max_x = $font_size + ($this->iscale * 3);
                                        } else { // numbers, capitals or unicode
                                                $min_x = $font_size + ($this->iscale * 2);
                                                $max_x = $font_size + ($this->iscale * 5);
                                        }
                                         
                                        $x += rand((int)$min_x,(int) $max_x);
                                } //for loop
                        } // angled or multi-color
                } //else ttf font
                //$this->im = $this->tmpimg;
                //$this->output();
        } //function

References $i, $x, image_height, image_width, multi_text_color, text_angle_maximum, text_angle_minimum, and use_multi_text.

Referenced by doImage().

frand()

Securimage::frand

(

)

Generate random number less than 1.

Since

2.0 @access private

Returns

float

Definition at line 1367 of file securimage.php.

        {
                return 0.0001*rand(0,9999);
        }

Referenced by distortedCopy(), and drawLines().

generateCode()

Securimage::generateCode

(

$len

)

Generate a code.

@access private

Parameters

int

$len

The code length

Returns

string

Definition at line 1021 of file securimage.php.

        {
                $code = '';
 
                for($i = 1, $cslen = strlen($this->charset??""); $i <= $len; ++$i) {
                        $code .= $this->charset[rand(0, $cslen - 1)];
                }
                return $code;
        }

References $code, and $i.

Referenced by createCode().

generateMP3()

Securimage::generateMP3

(

$letters

)

Generate an mp3 file by concatenating individual files.

Since

1.0.4 @access private

Parameters

array

$letters

Array of letters to build a file from

Returns

string MP3 file data

Definition at line 1339 of file securimage.php.

        {
                $data_len    = 0;
                $files       = array();
                $out_data    = '';
 
                foreach ($letters as $letter) {
                        $filename = $this->audio_path . strtoupper($letter) . '.mp3';
 
                        $fp   = fopen($filename, 'rb');
                        $data = fread($fp, filesize($filename)); // read file in
 
                        $this->scrambleAudioData($data, 'mp3');
                        $out_data .= $data;
 
                        fclose($fp);
                }
 
 
                return $out_data;
        }

References $data, $letter, and scrambleAudioData().

Referenced by getAudibleCode().

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generateWAV()

Securimage::generateWAV

(

$letters

)

Generate a wav file by concatenating individual files.

Since

1.0.1 @access private

Parameters

array

$letters

Array of letters to build a file from

Returns

string WAV file data

Definition at line 1231 of file securimage.php.

        {
                $data_len    = 0;
                $files       = array();
                $out_data    = '';
 
                foreach ($letters as $letter) {
                        $filename = $this->audio_path . strtoupper($letter) . '.wav';
 
                        $fp = fopen($filename, 'rb');
 
                        $file = array();
 
                        $data = fread($fp, filesize($filename)); // read file in
 
                        $header = substr($data, 0, 36);
                        $body   = substr($data, 44);
 
 
                        $data = unpack('NChunkID/VChunkSize/NFormat/NSubChunk1ID/VSubChunk1Size/vAudioFormat/vNumChannels/VSampleRate/VByteRate/vBlockAlign/vBitsPerSample', $header);
 
                        $file['sub_chunk1_id']   = $data['SubChunk1ID'];
                        $file['bits_per_sample'] = $data['BitsPerSample'];
                        $file['channels']        = $data['NumChannels'];
                        $file['format']          = $data['AudioFormat'];
                        $file['sample_rate']     = $data['SampleRate'];
                        $file['size']            = $data['ChunkSize'] + 8;
                        $file['data']            = $body;
 
                        if ( ($p = strpos($file['data'], 'LIST')) !== false) {
                                // If the LIST data is not at the end of the file, this will probably break your sound file
                                $info         = substr($file['data'], $p + 4, 8);
                                $data         = unpack('Vlength/Vjunk', $info);
                                $file['data'] = substr($file['data'], 0, $p);
                                $file['size'] = $file['size'] - (strlen($file['data']) - $p);
                        }
 
                        $files[] = $file;
                        $data    = null;
                        $header  = null;
                        $body    = null;
 
                        $data_len += strlen($file['data']);
 
                        fclose($fp);
                }
 
                $out_data = '';
                for($i = 0; $i < sizeof($files); ++$i) {
                        if ($i == 0) { // output header
                                $out_data .= pack('C4VC8', ord('R'), ord('I'), ord('F'), ord('F'), $data_len + 36, ord('W'), ord('A'), ord('V'), ord('E'), ord('f'), ord('m'), ord('t'), ord(' '));
 
                                $out_data .= pack('VvvVVvv',
                                16,
                                $files[$i]['format'],
                                $files[$i]['channels'],
                                $files[$i]['sample_rate'],
                                $files[$i]['sample_rate'] * (($files[$i]['bits_per_sample'] * $files[$i]['channels']) / 8),
                                ($files[$i]['bits_per_sample'] * $files[$i]['channels']) / 8,
                                $files[$i]['bits_per_sample'] );
 
                                $out_data .= pack('C4', ord('d'), ord('a'), ord('t'), ord('a'));
 
                                $out_data .= pack('V', $data_len);
                        }
 
                        $out_data .= $files[$i]['data'];
                }
 
                $this->scrambleAudioData($out_data, 'wav');
                return $out_data;
        }

References $data, $file, $header, $i, $letter, $p, and scrambleAudioData().

Referenced by getAudibleCode().

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getAudibleCode()

Securimage::getAudibleCode

(

$format = 'wav'

)

Get WAV or MP3 file data of the spoken code.

This is appropriate for output to the browser as audio/x-wav or audio/mpeg

Since

1.0.1

Returns

string WAV or MP3 data

Definition at line 1107 of file securimage.php.

        {
                $letters = array();
                $code    = $this->getCode();
 
                if ($code == '') {
                        $this->createCode();
                        $code = $this->getCode();
                }
 
                for($i = 0; $i < strlen($code); ++$i) {
                        $letters[] = $code[$i];
                }
 
                if ($format == 'mp3') {
                        return $this->generateMP3($letters);
                } else {
                        return $this->generateWAV($letters);
                }
        }

References $code, $i, createCode(), generateMP3(), generateWAV(), and getCode().

Referenced by outputAudioFile().

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getBackgroundFromDirectory()

Securimage::getBackgroundFromDirectory

(

)

Return the full path to a random gif, jpg, or png from the background directory.

@access private

See also

Securimage\$background_directory

Returns

mixed false if none found, string $path if found

Definition at line 787 of file securimage.php.

        {
                $images = array();
 
                if ($dh = opendir($this->background_directory)) {
                        while (($file = readdir($dh)) !== false) {
                                if (preg_match('/(jpg|gif|png)$/i', $file)) $images[] = $file;
                        }
 
                        closedir($dh);
 
                        if (sizeof($images) > 0) {
                                return rtrim($this->background_directory, '/') . '/' . $images[rand(0, sizeof($images)-1)];
                        }
                }
 
                return false;
        }

References $file, and background_directory.

Referenced by setBackground().

getCode()

Securimage::getCode

(

)

Get the captcha code.

Since

1.0.1

Returns

string

Definition at line 1201 of file securimage.php.

        {
                if (isset($_SESSION['securimage_code_value']) && !empty($_SESSION['securimage_code_value'])) {
                        return strtolower($_SESSION['securimage_code_value']);
                } else {
                        if ($this->sqlite_handle == false) $this->openDatabase();
                        
                        return $this->getCodeFromDatabase(); // attempt to get from database, returns empty string if sqlite is not available or disabled
                }
        }

References getCodeFromDatabase(), and openDatabase().

Referenced by getAudibleCode().

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getCodeFromDatabase()

Securimage::getCodeFromDatabase

(

)

Get stored captcha code from sqlite database based on ip address hash.

@access private

Since

2.0.1

Returns

string captcha code

Definition at line 1463 of file securimage.php.

        {
    $code = '';
 
    if ($this->use_sqlite_db && $this->sqlite_handle !== false) {
        $ip = $this->getIPHash();
        
        $res = sqlite_query($this->sqlite_handle, "SELECT * FROM codes WHERE iphash = '$ip'");
        if ($res && sqlite_num_rows($res) > 0) {
                $res = sqlite_fetch_array($res);
                
                if ($this->isCodeExpired($res['created']) == false) {
                        $code = $res['code'];
                }
        }
    }
    
    return $code;
        }

References $code, $res, getIPHash(), and isCodeExpired().

Referenced by getCode(), and validate().

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getIPHash()

Securimage::getIPHash

(

)

Get hashed IP address of remote user.

@access private

Since

2.0.1

Returns

string

Definition at line 1401 of file securimage.php.

        {
                return strtolower(md5($_SERVER['REMOTE_ADDR']));
        }

Referenced by clearCodeFromDatabase(), getCodeFromDatabase(), and saveCodeToDatabase().

isCodeExpired()

Securimage::isCodeExpired

(

$creation_time

)

Check a code to see if it is expired based on creation time.

@access private

Since

2.0.1

Parameters

$creation_time

unix timestamp of code creation time

Returns

bool true if code has expired, false if not

Definition at line 1522 of file securimage.php.

        {
                $expired = true;
                
                if (!is_numeric($this->expiry_time) || $this->expiry_time < 1) {
                        $expired = false;
                } else if (time() - $creation_time < $this->expiry_time) {
                        $expired = false;
                }
                
                return $expired;
        }

Referenced by getCodeFromDatabase(), and validate().

openDatabase()

Securimage::openDatabase

(

)

Open SQLite database.

@access private

Since

2.0.1

Returns

bool true if database was opened successfully

Definition at line 1413 of file securimage.php.

        {
                $this->sqlite_handle = false;
                
                if ($this->use_sqlite_db && function_exists('sqlite_open')) {
                        $this->sqlite_handle = sqlite_open($this->sqlite_database, 0666, $error);
                        
                        if ($this->sqlite_handle !== false) {
                                $res = sqlite_query($this->sqlite_handle, "PRAGMA table_info(codes)");
                                if (sqlite_num_rows($res) == 0) {
                                  sqlite_query($this->sqlite_handle, "CREATE TABLE codes (iphash VARCHAR(32) PRIMARY KEY, code VARCHAR(32) NOT NULL, created INTEGER)");
                                }
                        }
                        
                        return $this->sqlite_handle != false;
                }
                
                return $this->sqlite_handle;
        }

References $error, and $res.

Referenced by getCode(), saveCodeToDatabase(), and validate().

output()

Securimage::output

(

)

Output image to the browser.

@access private

Definition at line 1069 of file securimage.php.

        {
                header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
                header("Last-Modified: " . gmdate("D, d M Y H:i:s") . "GMT");
                header("Cache-Control: no-store, no-cache, must-revalidate");
                header("Cache-Control: post-check=0, pre-check=0", false);
                header("Pragma: no-cache");
 
                switch($this->image_type)
                {
                        case SI_IMAGE_JPEG:
                                header("Content-Type: image/jpeg");
                                imagejpeg($this->im, null, 90);
                                break;
 
                        case SI_IMAGE_GIF:
                                header("Content-Type: image/gif");
                                imagegif($this->im);
                                break;
 
                        default:
                                header("Content-Type: image/png");
                                imagepng($this->im);
                                break;
                }
 
                imagedestroy($this->im);
                exit;
        }

References exit, and image_type.

Referenced by doImage().

outputAudioFile()

Securimage::outputAudioFile

(

)

Output audio file with HTTP headers to browser.

$sound = new Securimage(); $sound->audio_format = 'mp3'; $sound->outputAudioFile();

Since

2.0

Definition at line 624 of file securimage.php.

        {
                if (strtolower($this->audio_format) == 'wav') {
                        header('Content-type: audio/x-wav');
                        $ext = 'wav';
                } else {
                        header('Content-type: audio/mpeg'); // default to mp3
                        $ext = 'mp3';
                }
 
                header("Content-Disposition: attachment; filename=\"securimage_audio.{$ext}\"");
                header('Cache-Control: no-store, no-cache, must-revalidate');
                header('Expires: Sun, 1 Jan 2000 12:00:00 GMT');
                header('Last-Modified: ' . gmdate('D, d M Y H:i:s') . 'GMT');
 
                $audio = $this->getAudibleCode($ext);
 
                header('Content-Length: ' . strlen($audio));
 
                echo $audio;
                exit;
        }

References $ext, audio_format, exit, and getAudibleCode().

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purgeOldCodesFromDatabase()

Securimage::purgeOldCodesFromDatabase

(

)

Purge codes over a day old from database.

@access private

Since

2.0.1

Definition at line 1504 of file securimage.php.

        {
                if ($this->use_sqlite_db && $this->sqlite_handle !== false) {
                        $now   = time();
                        $limit = (!is_numeric($this->expiry_time) || $this->expiry_time < 1) ? 86400 : $this->expiry_time;
                        
                        sqlite_query($this->sqlite_handle, "DELETE FROM codes WHERE $now - created > $limit");
                }
        }

References $limit.

readCodeFromFile()

Securimage::readCodeFromFile

(

)

Reads a word list file to get a code.

@access private

Since

1.0.2

Returns

mixed false on failure, a word on success

Definition at line 1038 of file securimage.php.

        {
                $fp = @fopen($this->wordlist_file, 'rb');
                if (!$fp) return false;
 
                $fsize = filesize($this->wordlist_file);
                if ($fsize < 32) return false; // too small of a list to be effective
 
                if ($fsize < 128) {
                        $max = $fsize; // still pretty small but changes the range of seeking
                } else {
                        $max = 128;
                }
 
                fseek($fp, rand(0, $fsize - $max), SEEK_SET);
                $data = fread($fp, 128); // read a random 128 bytes from file
                fclose($fp);
                $data = preg_replace("/\r?\n/", "\n", $data);
 
                $start = strpos($data, "\n", rand(0, 100)) + 1; // random start position
                $end   = strpos($data, "\n", $start);           // find end of word
 
                return strtolower(substr($data, $start, $end - $start)); // return substring in 128 bytes
        }

References $data, $end, $max, and $start.

Referenced by createCode().

saveCodeToDatabase()

Securimage::saveCodeToDatabase

(

)

Save captcha code to sqlite database.

@access private

Since

2.0.1

Returns

bool true if code was saved, false if not

Definition at line 1440 of file securimage.php.

        {
                $success = false;
                
                $this->openDatabase();
                
                if ($this->use_sqlite_db && $this->sqlite_handle !== false) {
                        $ip = $this->getIPHash();
                        $time = time();
                        $code = $_SESSION['securimage_code_value']; // hash code for security - if cookies are disabled the session still exists at this point
                        $success = sqlite_query($this->sqlite_handle, "INSERT OR REPLACE INTO codes(iphash, code, created) VALUES('$ip', '$code', $time)");
                }
                
                return $success !== false;
        }

References $code, getIPHash(), and openDatabase().

Referenced by saveData().

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saveData()

Securimage::saveData

(

)

Save the code in the session.

@access private

Definition at line 1150 of file securimage.php.

        {
                $_SESSION['securimage_code_value'] = strtolower($this->code);
                $_SESSION['securimage_code_ctime'] = time();
                
                $this->saveCodeToDatabase();
        }

References saveCodeToDatabase().

Referenced by createCode().

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scrambleAudioData()

Securimage::scrambleAudioData	(	&	$data,
			$format )

Randomly modify the audio data to scramble sound and prevent binary recognition.

Take care not to "break" the audio file by leaving the header data intact.

Since

2.0 @access private

Parameters

$data

Sound data in mp3 of wav format

Definition at line 1312 of file securimage.php.

        {
                if ($format == 'wav') {
                        $start = strpos($data, 'data') + 4; // look for "data" indicator
                        if ($start === false) $start = 44;  // if not found assume 44 byte header
                } else { // mp3
                        $start = 4; // 4 byte (32 bit) frame header
                }
                 
                $start  += rand(1, 64); // randomize starting offset
                $datalen = strlen($data) - $start - 256; // leave last 256 bytes unchanged
                 
                for ($i = $start; $i < $datalen; $i += 64) {
                        $ch = ord($data[$i]);
                        if ($ch < 9 || $ch > 119) continue;
 
                        $data[$i] = chr($ch + rand(-8, 8));
                }
        }

References $data, $i, and $start.

Referenced by generateMP3(), and generateWAV().

setAudioPath()

Securimage::setAudioPath

(

$audio_directory

)

Set the path to the audio directory.

Since

1.0.4

Returns

bool true if the directory exists and is readble, false if not

Definition at line 1134 of file securimage.php.

        {
                if (is_dir($audio_directory) && is_readable($audio_directory)) {
                        $this->audio_path = $audio_directory;
                        return true;
                } else {
                        return false;
                }
        }

setBackground()

Securimage::setBackground

(

)

Set the background of the CAPTCHA image.

@access private

Definition at line 747 of file securimage.php.

        {
                imagefilledrectangle($this->im, 0, 0, $this->image_width * $this->iscale, $this->image_height * $this->iscale, $this->gdbgcolor);
    imagefilledrectangle($this->tmpimg, 0, 0, $this->image_width * $this->iscale, $this->image_height * $this->iscale, $this->gdbgcolor);
    
                if ($this->bgimg == '') {
                        if ($this->background_directory != null && is_dir($this->background_directory) && is_readable($this->background_directory)) {
                                $img = $this->getBackgroundFromDirectory();
                                if ($img != false) {
                                        $this->bgimg = $img;
                                }
                        }
                }
 
                $dat = @getimagesize($this->bgimg);
                if($dat == false) { 
                        return;
                }
 
                switch($dat[2]) {
                        case 1:  $newim = @imagecreatefromgif($this->bgimg); break;
                        case 2:  $newim = @imagecreatefromjpeg($this->bgimg); break;
                        case 3:  $newim = @imagecreatefrompng($this->bgimg); break;
                        case 15: $newim = @imagecreatefromwbmp($this->bgimg); break;
                        case 16: $newim = @imagecreatefromxbm($this->bgimg); break;
                        default: return;
                }
 
                if(!$newim) return;
 
                imagecopyresized($this->im, $newim, 0, 0, 0, 0, $this->image_width, $this->image_height, imagesx($newim), imagesy($newim));
        }

References $img, background_directory, bgimg, getBackgroundFromDirectory(), image_height, and image_width.

Referenced by doImage().

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show()

Securimage::show

(

$background_image = ""

)

Generate a code and output the image to the browser.

<?php include 'securimage.php'; $securimage = new Securimage(); $securimage->show('bg.jpg'); ?>

Parameters

string

$background_image

The path to an image to use as the background for the CAPTCHA

Definition at line 583 of file securimage.php.

        {
                if($background_image != "" && is_readable($background_image)) {
                        $this->bgimg = $background_image;
                }
 
                $this->doImage();
        }

References bgimg, and doImage().

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validate()

Securimage::validate

(

)

Validate the code to the user code.

@access private

Definition at line 1164 of file securimage.php.

        {
            $code='';
                // retrieve code from session, if no code exists check sqlite database if supported.
                
                if (isset($_SESSION['securimage_code_value']) && trim($_SESSION['securimage_code_value']) != '') {
                        if ($this->isCodeExpired($_SESSION['securimage_code_ctime']) == false) { 
                          $code = $_SESSION['securimage_code_value'];
                        }
                } else if ($this->use_sqlite_db == true && function_exists('sqlite_open')) { // no code in session - may mean user has cookies turned off
                        $this->openDatabase();
                        $code = $this->getCodeFromDatabase();
                } else {
                        // session code invalid or non-existant and code not found in sqlite db or sqlite is not available
                        $code = '';
                }
                
                $code               = trim(strtolower($code));
                $code_entered       = trim(strtolower($this->code_entered));
                $this->correct_code = false;
                
                if ($code != '') {
                        if ($code == $code_entered) {
                          $this->correct_code = true;
                          $_SESSION['securimage_code_value'] = '';
                          $_SESSION['securimage_code_ctime'] = '';
                          $this->clearCodeFromDatabase();
                  }
                }
        }

References $code, $code_entered, clearCodeFromDatabase(), getCodeFromDatabase(), isCodeExpired(), and openDatabase().

Referenced by check().

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Field Documentation

$audio_format

Securimage::$audio_format

Definition at line 349 of file securimage.php.

$audio_path

Securimage::$audio_path

Definition at line 342 of file securimage.php.

$background_directory

Securimage::$background_directory = null

Definition at line 248 of file securimage.php.

$bgimg

Securimage::$bgimg

Definition at line 421 of file securimage.php.

$charset

Securimage::$charset

Definition at line 145 of file securimage.php.

$code

Securimage::$code

Definition at line 429 of file securimage.php.

Referenced by check(), generateCode(), getAudibleCode(), getCodeFromDatabase(), saveCodeToDatabase(), and validate().

$code_entered

Securimage::$code_entered

Definition at line 437 of file securimage.php.

Referenced by validate().

$code_length

Securimage::$code_length

Definition at line 136 of file securimage.php.

$correct_code

Securimage::$correct_code

Definition at line 445 of file securimage.php.

$draw_lines_over_text

Securimage::$draw_lines_over_text

Definition at line 316 of file securimage.php.

$expiry_time

Securimage::$expiry_time

Definition at line 367 of file securimage.php.

$gd_font_file

Securimage::$gd_font_file

Definition at line 169 of file securimage.php.

$gd_font_size

Securimage::$gd_font_size

Definition at line 178 of file securimage.php.

$gdbgcolor

Securimage::$gdbgcolor

Definition at line 493 of file securimage.php.

$gdlinecolor

Securimage::$gdlinecolor

Definition at line 461 of file securimage.php.

$gdmulticolor

Securimage::$gdmulticolor

Definition at line 469 of file securimage.php.

$gdsignaturecolor

Securimage::$gdsignaturecolor

Definition at line 485 of file securimage.php.

$gdtextcolor

Securimage::$gdtextcolor

Definition at line 477 of file securimage.php.

$im

Securimage::$im

Definition at line 396 of file securimage.php.

$image_bg_color

Securimage::$image_bg_color

Definition at line 237 of file securimage.php.

$image_height

Securimage::$image_height

Definition at line 121 of file securimage.php.

$image_signature

Securimage::$image_signature

Definition at line 324 of file securimage.php.

$image_type

Securimage::$image_type

Definition at line 129 of file securimage.php.

$image_width

Securimage::$image_width

Definition at line 114 of file securimage.php.

$iscale

Securimage::$iscale

Definition at line 413 of file securimage.php.

$line_color

Securimage::$line_color

Definition at line 308 of file securimage.php.

$multi_text_color

Securimage::$multi_text_color

Definition at line 273 of file securimage.php.

$num_lines

Securimage::$num_lines

Definition at line 301 of file securimage.php.

$perturbation

Securimage::$perturbation

Definition at line 202 of file securimage.php.

$session_name

Securimage::$session_name = ''

Definition at line 358 of file securimage.php.

$signature_color

Securimage::$signature_color

Definition at line 332 of file securimage.php.

$signature_font

Securimage::$signature_font

Definition at line 334 of file securimage.php.

$sqlite_database

Securimage::$sqlite_database

Definition at line 378 of file securimage.php.

$sqlite_handle

Securimage::$sqlite_handle

Definition at line 453 of file securimage.php.

$text_angle_maximum

Securimage::$text_angle_maximum

Definition at line 221 of file securimage.php.

$text_angle_minimum

Securimage::$text_angle_minimum

Definition at line 212 of file securimage.php.

$text_color

Securimage::$text_color

Definition at line 258 of file securimage.php.

$text_transparency_percentage

Securimage::$text_transparency_percentage

Definition at line 290 of file securimage.php.

$text_x_start

Securimage::$text_x_start

Definition at line 230 of file securimage.php.

$tmpimg

Securimage::$tmpimg

Definition at line 404 of file securimage.php.

$ttf_file

Securimage::$ttf_file

Definition at line 194 of file securimage.php.

$use_gd_font

Securimage::$use_gd_font

Definition at line 185 of file securimage.php.

$use_multi_text

Securimage::$use_multi_text

Definition at line 266 of file securimage.php.

$use_sqlite_db

Securimage::$use_sqlite_db

Use an SQLite database for storing codes as a backup to sessions.

Note: Sessions will still be used

Definition at line 384 of file securimage.php.

$use_transparent_text

Securimage::$use_transparent_text

Definition at line 281 of file securimage.php.

$use_wordlist

Securimage::$use_wordlist = false

Definition at line 159 of file securimage.php.

$wordlist_file

Securimage::$wordlist_file

Definition at line 152 of file securimage.php.

---

The documentation for this class was generated from the following file:

• html/securimage/securimage.php