Problem with inserting an image in a form using GD!

Question

Hi everybody,

I'm trying to develop a captcha class for my website everything was doing fine until I tried to embed the image generated with PHP GD inside my subscription form!

Here is the code of my class:

<?php
//captcha.php
header("Content-type: image/png");


class Captcha  {


  // some attributes bla bla

  public function __construct($new_string_length,$new_width_picture,
                              $new_height_picture,$new_string_color) {

    $this->string_length = $new_string_length;
    $this->width_picture = $new_width_picture;
    $this->height_picture = $new_height_picture;
    $this->string_color = $new_string_color;

  }

  public function getString() {
    return $this->string;
  }

  public function generateRandomString() {
    $str = "";
    $basket = "abcdefghijklmnopqrstuvwxyz0123456789";
    $basket_length = strlen($basket);
    srand ((double) microtime() * 1000000);
    for($i=0;$i<$this->string_length;$i++) {

        $generated_pos = rand(0,$basket_length);
        $str_substr = substr($basket,$generated_pos-1,1);
        if(!is_numeric($str_substr)) { 
          // if the character picked up isn't numeric
          if(rand(0,1)==1) {
            // we randomly upper the character
            $str_substr = strtoupper($str_substr);
          }
        }
        $str = $str.$str_substr;
    }

    $this->string = $str;
  } 

  **public function generatePictureFromString($new_string) {
      $root_fonts = '../fonts/';
      srand ((double) microtime() * 1000000);
      $list_fonts = array('ABODE.ttf','acme.ttf','Alcohole.ttf',
                   'Anarchistica.ttf','AMERIKAA.ttf');

      $image = @imagecreatetruecolor($this->width_picture,$this->height_picture);
      $noir  = imagecolorallocate($image,0,0,0);
      $clr = explode('/',$this->string_color);
      $clr = imagecolorallocate($image,$clr[0],$clr[1],$clr[2]);




      for($i=0;$i<strlen($new_string);$i++) {       
           imagettftext($image,rand(($this->height_picture/4.3),($this->height_picture)/4.2),
           rand(-45,45),($this->width_picture)/(5*$this->string_length)+($this->width_picture)/($this->string_length)*$i,0.6*($this->height_picture),$clr,
           $root_fonts.$list_fonts[rand(0,count($list_fonts)-1)],substr($new_string,$i,1));
      }

      imagepng($image);
      imagedestroy($image);

  }**

}

I willingly avoided to show some useless part of the class. The class itself works perfectly when I call the generatePictureFromString(..) method like this:

<?php
//testeur_classe.php
require_once '../classes/captcha.php';

$captcha = new Captcha(5,200,80,"255/255/255");
$captcha->generateRandomString();
$str  = $captcha->getString();
$captcha->generatePictureFromString($str); 
?>

But when I try to insert the picture generated in my form using:

<img src="<?php echo PATH_ROOT.'classes\testeur_classe.php'; ?>"/>

nothing is displayed!

How am I supposed to do that ?

Thank you!

Answer 1

You need to make sure that the image src is a valid URL to the script. Looking at the backslash in there my guess would be that that is in fact a filesystem path.

Answer 2

OK: What do you see if you open classes\testeur_classe.php in the browser? (p.s. the same question as Ryan Graham asked you in question comment)

OK: I think you must set correct headers before picture output like:

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

p.s.

This code works, just tried it on my machine. You must have bug on <img src="..." or <base href="" if you have one. Could you show us your html output so we can see what could be the problem?