[Javascript/PHP] Click Captcha

[Ron_Hickey]

1) CODE TITLE: Click Captcha

2) AUTHOR NAME/NOTES:

3) DESCRIPTION: Requirements - php 4.3 or greater with GD support.

Click Captcha is a randomly generated gif file that is dynamically displayed
in a random area below form with 9 random color combinations and the
click number is randomly displayed to the right or left making 18 different
images with random numbers from 11 to 99 the generated gif file is less than 0.39 KB.

4) URL TO CODE: http://6tx.net/sc/ccode.html

or, ATTACHED BELOW (see #3 in guidelines below):

[thetestingsite]

Nice script, looks simple to integrate into a website and looks simple enough to edit (or configure for your own use).

Good job.

[tech_support]

It's so hard to see though.

[djr33]

Interesting. It works fairly well, but there are two problems--
1. The numbers are actually fairly hard to read... good for the spambots, but bad for users who don't have great eyesight. I've got 20/20, and a fairly bright monitor, and it's tough.
2. It seems that the spambot could, potentially, be configured to use the javascript source to find where it submits. Doing it serverside would be the only secure way, allowing for not having the 'correct answer' in the source.

Also, there are odds involved in this. A bot wouldn't mind trying this 20 times, one of which would likely be correct, even if it's just "guessing". Captchas work in the first place because you must read then interpret what is asked for, not just find/guess it.


EDIT: I was looking at the demo, so I hadn't refreshed to see your post, Tech.


Note: I also changed the title to something more descriptive; that's always helpful.

[Twey]

It really needs to have an associated audio file too, for visually impaired users.

[djr33]

Audio wouldn't work in any way for this, since it's a matching game.
Mouseover sound clips of various numbers?
"Click the area that when rolled over says '42'."

[tech_support]

That'll work.

[Ron_Hickey]

Thank you everyone for your input.

The point of a click captcha vs. one that you type.
Many use auto form fill and it is much faster to click once
vs. type 5 to 10 or more hard to see characters

All The Best,
Ron

[tech_support]

You could make JS to clear the forms on onload.

[Ron_Hickey]

You could make JS to clear the forms on onload.

I made the form to demo Captcha and values are pre set.

I changed code to make it easier to see
numbers.

All The Best,
Ron