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pauldreed
03-21-2006, 10:40 PM
I use 'Formail' for visitors to complete an online form, which although works fine, has recently recorded a number of false submissions, which I suspect are submitted via a virus or other 'non human' origin. (logfile lists no browser)
To stop these, is it possible to have force the user to retype a number of letters from an image, to confirm 'human' submission, just like a lot of commercial sites?

Twey
03-21-2006, 10:55 PM
Yes, but these images should be generated via a server-side script. Using PHP (http://www.php.net/), the GD (http://www.boutell.com/gd/) image-manipulation library allows you to generate an image dynamically. There is no equivalent for the audio file you should use in tandem (for visually-impaired users), but festival (http://www.cstr.ed.ac.uk/projects/festival/) does a nice job, and you can call it with shell_exec (http://www.php.net/shell-exec)().

pauldreed
03-22-2006, 08:50 PM
This looks heavy stuff for a new user!!
Are you aware of an easy way to acheive this, some code which is already written, or a script file?

Twey
03-22-2006, 09:47 PM
http://www.blueeye.us/wordpress/?p=5
I'm not sure about audio-generation. This use of festival requires more of a knowledge of shell usage than PHP, though, so you should be OK.

pauldreed
03-22-2006, 10:35 PM
http://www.blueeye.us/wordpress/?p=5
I'm not sure about audio-generation. This use of festival requires more of a knowledge of shell usage than PHP, though, so you should be OK.
But isn't this just for Wordpress?
I have a form which is submitted via Formail, to email. Are you suggesting that it could be modded to work with a form?
The form is at http://www.safeinsouthyorks.co.uk/form.html which I am trying to protect from automated posts.