Re: Going from simple to super CAPTCHA
| From: | Tijnema | Date: | Tue, 12 Jun 2007 19:46:32 +0000 |
| Subject: | Re: Going from simple to super CAPTCHA | ||
| References: | 1 2 3 4 5 6 7 8 9 10 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-256761@lists.php.net to get a copy of this message | ||
On 6/12/07, Robert Cummings <robert@interjinn.com> wrote:
On Tue, 2007-06-12 at 15:06 -0400, Daniel Brown wrote:Yes noticed that problem too, but this seems quite easy to crack, Get the text from the image, get the color of the text and search for tha tcolor circle. Tijnema Btw, I clicked the pixel in the middle, and did 10 refreshes, and I had 5 right....Okay, here's something I whipped up today:http://pilotpig.com/captcha/index.phpWorks pretty well, but keep in mind that it's in the very earlystages. I randomized the position and size to assist in throwing off Turing detection, and added color not only to screw with the color-detection schemes, but also in case it overlays the target bubble. It's 600x400, so that's 240,000 potential spots to click, with random size, location, and area coordinates thrown in the mix. Nice, one problem though... the text is unreadable on some backgrounds. I suggest you outline it or something. Easy to do by drawing the font 5 times. 4 times for the outline where you offset the drawing location by: (-1, 0), (0,1), (1,0), (0,1) Then change colour and draw the font at the original location. Cheers, Rob.