I added image confirmation to a guestbook and even though it works greate for most people, some people have problem and I can't seem to figure out why this happens. Note that I'm not talking about the same guestbook on one server but the guestbook is on people's own hosting server.
The php code to create the image can't be simpler:
*confirm_image.php:*
$datekey = date("F j");
$rcode = hexdec(md5($_SERVER[HTTP_USER_AGENT] . $cfg_sitekey . $random_num . $datekey));
$code = substr($rcode, 2, 6);
$image = ImageCreateFromJPEG("images/code_bg.jpg");
$text_color = ImageColorAllocate($image, 80, 80, 80);
Header("Content-type: image/jpeg");
ImageString ($image, 5, 12, 2, $code, $text_color);
ImageJPEG($image, '', 75);
ImageDestroy($image);
Most people get a nice image but some people get only, what appears to be, garbage:
JFIF;CREATOR: gd-jpeg v1.0 (using IJG JPEG v62), quality = 75 C $.' ",# (7),01444 '9=82<.342C 2! !22222222222222222222222222222222222222222222222222
...snip...
For the complete output have a look here:
http://www.samuel-area.de/phpbook/confirm_image.php
Do you know what is going wrong here?
Not entirely, but when I go to that URL and check the headers (Live HTTP header extension in firefox) I get this:
HTTP/1.x 200 OK
Date: Wed, 05 Apr 2006 20:02:02 GMT
Server: Apache/2.0.53 (Fedora)
X-Powered-By: PHP/4.3.11
Content-Length: 1501
Connection: close
Content-Type: text/html; charset=iso-8859-1
Notice that last one... I see you set it up above, but it isn't sticking....
-philip