Captcha image not loading? - php

Question

How do I get this to load? Right now, it's not showing any image at all... I'm not really that great at creating captcha's because I usually never do this.
captcha.php:
<?php
$string = '';
for ($i = 0; $i < 5; $i++) {
// this numbers refer to numbers of the ascii table (lower case)
$string .= chr(rand(97, 122));
}
$image = imagecreatetruecolor(170, 60);
$color = imagecolorallocate($image, 200, 100, 90); // red
$white = imagecolorallocate($image, 255, 255, 255);
imagefilledrectangle($image,0,0,399,99,$white);
imagettftext ($image, 30, 0, 10, 40, $color, ASSETPATH."arial.ttf", $string);
header("Content-type: image/png");
imagepng($image);
?>
register.php:
<?php echo '<img src="'.ASSETPATH.'img/captcha.php" />'; ?>
My asset path IS correct because I'm using it elsewhere and it loads perfectly fine. Is the MVC format of this project messing it up somehow??

Answer 1

How about using one of the captcha services like recaptcha?

Answer 2

Judging by your use of this constant ASSETPATH both for you image URI as well as the fontfile path in imagettftext I can only assume you have your fontfile stored in the same path as that of your image?
If this is not the case, or the file could not be opened there, PHP will throw a Warning of imagettftext(): Invalid font filename. If display_errors is set to On in your php.ini (you can check phpinfo to verify this) this means the error message will be sent to the output stream along with your image data (i.e. corrupting the image data and cause your browser not to display the image). This would also prevent the headers from being modify since the error would have occurred before your call to header.
However, if display_errors is not turned on and PHP could not find the fontfile you supplied or it could not be open for any reason (e.g. permissions) the result will be a blank 170x60 PNG image.
If I test your code locally it proves to work as expected, as long as I supply PHP with the correct absolute path to my truetype font file.
For example, I have some truetype fonts on my system stored at /usr/share/fonts/truetype/, which is definitely not in my webroot as I don't normally keep my font files there. Note, also, that my PHP user has sufficient permissions to read from this path.
Now, if I supply PHP with the correct absolute path to the truetype font file that I would like to use I get the following image using your code...
$string = '';
for ($i = 0; $i < 5; $i++) {
// this numbers refer to numbers of the ascii table (lower case)
$string .= chr(rand(97, 122));
}
$image = imagecreatetruecolor(170, 60);
$color = imagecolorallocate($image, 200, 100, 90); // red
$white = imagecolorallocate($image, 255, 255, 255);
imagefilledrectangle($image,0,0,399,99,$white);
imagettftext ($image, 30, 0, 10, 40, $color, '/usr/share/fonts/truetype/ttf-dejavu/DejaVuSans-ExtraLight.ttf', $string);
header("Content-type: image/png");
imagepng($image);
What you should try to do in order to debug this further is run the PHP script that generates the image by itself, with display_errors turned on and error_reporting set to -1 and if it is indeed the case that your font file is the problem you will see this in your error_log or in the error output displayed during testing that script with display_errors on.