New CAPTCHA

[MKruer]

How about a letter that a bot will see but a person will not.

How would you do that

Look at the last page about half way down. A bot can easly see the text, but humans cant.

[Mystie]

This might well be a crazy idea that would never work but my 9 yr old was reading this thread and decided he had an idea of his own to suggest. If nothing more- he's offering it out there so that he can see how realistic it is by your responses (yes, he understands CAPTCHA)

He envisions something similar to the Matrix' trickle where you've got a dozen or so lines moving down the screen at a pace like a slot machine- the user picks out the letters or numbers or grapes out of the line as its whizzing by and enters the word he spells at the end. Obviously he doesnt know how to make it what you guys would need, but he liked the rotating words and thought the matrix type thing would mean the person would have to actually sit there watching the screen to find out what the word was.

[MKruer]

There was something analogous to that posted a while back, but it was determined that this would make it ever easier to find the characters because now the bot would only have to detect pixels that change to spot the letter. However if you want to take that idea and have manual interaction to rotate a dial or something to revile the letters this would be a logic puzzle and would be much harder for a bot to decipher the text.

[Xore]

Hey, my first post in area51. Look at all the pretty colors.

First thought - I am so excited to see this thread. I have been following it for days. The captcha prototypes are very exciting.

I've said this before - I currently run about 8 phpBB sites and I'm getting hammered with spam registrations.

I downloaded a Perl script the other day that makes simple CAPTCHA images and I'm working on implementing my temporary solution. It works like this:

1. Replace the alphabet with symbols (the theory here is that OCR won't be able to decipher them).

2. On each CAPTCHA view, randomize the symbol names (one time "two wavy lines" is called ORT, another refresh it is called ZOD, etc.)

3. Provide a legend to the randomized names - the legend would provide a text description of the symbols. For example: "ZED is the symbol that looks like two crossed capital I characters"

4. If possible, the legend describing the names of the symbols would also be a CAPTCHA image.

5. Make the user identify 4-8 of these randomized symbols. Example: Zod Zod Ort Zod Zed.

Any thoughts on how effective this approach might be? Thanks!

I'm not sure which is sadder: the fact that you mentioned it, or the fact that i can still recognize it in spite quitting 2 years ago.

You need to cut back on the d2, man.

Edit: not a bad idea though. I developed a captcha with a similar idea, that hasn't been approved (yet) for olympus, which involves generating random patterns and associating multiple codes with distinct patterns, then showing the pattern that corresponds to the correct code in big, and asking the user to enter the corresponding code.

[ElbertF]

I decided to drop in some filled characters aswell.. And there is plenty of information in the back that only a computer would notice

How fast is your execution time and how much memory do you eat? Are your fonts GPL friendly? Have you considered true color fonts?

The execution time is in the picture (about 0.04s), but I have to say I haven't been able to test it on a decent server. I'm not sure about memory, how do I find out? I just used some Windows TT Fonts here, but offcourse they could easily be replaced. What's the advantage of True Color Fonts?

1. Replace the alphabet with symbols (the theory here is that OCR won't be able to decipher them).

There isn't one bot that can decipher all CAPTCHAS, they're all custom made. So if we'd be using symbols, it would be made to decipher just those (it could be programmed to read "‡" as an "A" for example).

[robertmf]

It looks like a new Captcha has finally been committed, and so I grabbed a snapshot to see how it looked.

I have to say, it's rather hard to understand some of the images. It looks rather difficult for bots to read (especially the first one) but also rather difficult for me to read. What do you think? It's a step in the right direction, at least.

I **hope** this isn't the final captcha style. I just tried to register with the star trek 'tester' forum and was unable to figure out the captcha. I think **dubious nodding head** there was a dripping 'L' for the center letter.

[dhn]

The Captcha is still being worked upon.

[DavidMJ]

The Captcha is still being worked upon.

Speaking of which, a new CAPTCHA option exists!

[MKruer]

So i dont have to download it, can someone post an image of the curret version of the CAPTCHA for phpbb3?

Thanks

[DavidMJ]

Sure
The answer is 53QRG6QD