imagegd

(PHP 4 >= 4.0.7, PHP 5)

imagegd — Output GD image to browser or file

Beschreibung

bool imagegd ( resource $image [, string $filename ] )

Outputs a GD image to the given filename.

Parameter-Liste

image: Eine von den verschiedenen Erzeugungsfunktionen wie imagecreatetruecolor() gelieferte Grafikressource.
filename: Der Pfad unter dem das Bild gespeichert werden soll. Ist dies nicht gesetzt oder NULL wird der rohe Bilddatenstrom direkt ausgegeben.

Rückgabewerte

Gibt bei Erfolg TRUE zurück. Im Fehlerfall wird FALSE zurückgegeben.

Beispiele

Beispiel #1 Outputting a GD image


<?php
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5,  "A Simple Text String", $text_color);

// Output the image
imagegd($im);

// Free up memory
imagedestroy($im);
?>

Beispiel #2 Saving a GD image


<?php
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5,  "A Simple Text String", $text_color);

// Save the gd image
// The file format for GD images is .gd, see http://www.libgd.org/GdFileFormats
imagegd($im, 'simple.gd');

// Free up memory
imagedestroy($im);
?>

Anmerkungen

Hinweis:
The GD format is commonly used to allow fast loading of parts of images. Note that the GD format is only usable in GD-compatible applications.

Siehe auch

imagegd2() - Output GD2 image to browser or file

add a note User Contributed Notes imagegd - [1 notes]

down

rohitkumar at cftechno dot com ¶

1 year ago


<?php



/*

* Captcha image for security 

*/



session_start();



class CaptchaSecurityImages {

 

   var $font = 'monofont.ttf';

 

   function generateCode($characters) {

      /* list all possible characters, similar looking characters and vowels have been removed */

      $possible = '23456789bcdfghjkmnpqrstvwxyz';

      $code = '';

      $i = 0;

      while ($i < $characters) { 

         $code .= substr($possible, mt_rand(0, strlen($possible)-1), 1);

         $i++;

      }

      return $code;

   }

 

   function CaptchaSecurityImages($width='120',$height='40',$characters='6') {

      $code = $this->generateCode($characters);

      /* font size will be 75% of the image height */

      $font_size = $height * 0.75;

      $image = imagecreate($width, $height) or die('Cannot initialize new GD image stream');

      /* set the colours */

      $background_color = imagecolorallocate($image, 255, 255, 255);

      $text_color = imagecolorallocate($image, 20, 40, 100);

      $noise_color = imagecolorallocate($image, 100, 120, 180);

      /* generate random dots in background */

      for( $i=0; $i<($width*$height)/3; $i++ ) {

         imagefilledellipse($image, mt_rand(0,$width), mt_rand(0,$height), 1, 1, $noise_color);

      }

      /* generate random lines in background */

      for( $i=0; $i<($width*$height)/150; $i++ ) {

         imageline($image, mt_rand(0,$width), mt_rand(0,$height), mt_rand(0,$width), mt_rand(0,$height), $noise_color);

      }

      /* create textbox and add text */

      $textbox = imagettfbbox($font_size, 0, $this->font, $code) or die('Error in imagettfbbox function');

      $x = ($width - $textbox[4])/2;

      $y = ($height - $textbox[5])/2;

      imagettftext($image, $font_size, 0, $x, $y, $text_color, $this->font , $code) or die('Error in imagettftext function');

      /* output captcha image to browser */

      header('Content-Type: image/jpeg');

      imagejpeg($image);

      imagedestroy($image);

      $_SESSION['security_code'] = $code;

   }

 

}

 

$width = isset($_GET['width']) && $_GET['width'] < 600 ? $_GET['width'] : '120';

$height = isset($_GET['height']) && $_GET['height'] < 200 ? $_GET['height'] : '40';

$characters = isset($_GET['characters']) && $_GET['characters'] > 2 ? $_GET['characters'] : '6';

 

$captcha = new CaptchaSecurityImages($width,$height,$characters);

 

?>

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