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Ron_Hickey
05-01-2007, 02:30 AM
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
05-01-2007, 02:38 AM
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
05-01-2007, 07:13 AM
It's so hard to see though.

djr33
05-01-2007, 07:18 AM
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
05-01-2007, 07:24 AM
It really needs to have an associated audio file too, for visually impaired users.

djr33
05-01-2007, 07:28 AM
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'." :D

tech_support
05-01-2007, 07:29 AM
That'll work.

Ron_Hickey
05-01-2007, 10:42 AM
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
05-01-2007, 10:43 AM
You could make JS to clear the forms on onload.

Ron_Hickey
05-01-2007, 11:03 AM
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

tech_support
05-01-2007, 11:05 AM
It's not exactly easier.

You could try making the numbers a different color, and like Twey said, have an audio recording for visual impared users.

mburt
05-01-2007, 04:23 PM
I like the idea though, it is original. Generally it's a typing-in thing, so this is kind of different. I think spambots are catching on to the input field captcha.

Ron_Hickey
05-01-2007, 09:48 PM
It really needs to have an associated audio file too, for visually impaired users.

Yes, good idea, I will keep in mind for next version.


I changed the dashed line color, should be easy to see for most.

All The Best,
Ron

thetestingsite
05-02-2007, 03:22 AM
It is much easier to see now; but as djr33 said before, the spambots could be configured to look at the javascript source and get the correct value (not exactly what was said, but close enough). Anyways, can't wait for the next version; especially if you get the audio substitute for the visually impaired.

Anyways, just my two cents worth.

Ron_Hickey
05-02-2007, 03:48 AM
the spambots could be configured to look at the javascript source and get the correct value

The Javascript is used to locate X coords onclick only, the spambot would have to be configured to decode, strip string and do calculations to know what coord to click

All The Best,
Ron

cr0w
05-02-2007, 04:00 AM
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

He's talking about users with autofill ;)