Extremely weak captcha

Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
Post Reply
Phygar

Extremely weak captcha

Post by Phygar »

There's this site that features a very weak captcha, and I've thought up a way that I think would work to solve it.

The images are like this:
Image
Image
There's always 5 letters, 5 lines, A-Z, no anti-aliasing, no rotation, and Verdana 18 pt bold, and 2 pixels between each letter

I figure I should convert them to monochrome
Image
Then simply try placing 18 pt bold Verdana characters in every pixel and record the X coordinate of every pixel where it fits entirely over black characters. I would find out if it fits over the black completely by just comparing the original image with an image that has the placed character and seeing if they changed at all. I would do this for every letter, then make sure that all of the letters had 2 pixels of space in between, and then just sort them by the x coordinate order.

Would this be an ok way to do this, or would there be a more effective way of doing it? The speed it needs to do this wouldn't really need to be that fast, jist faster than the speed of downloading the page/image, but would doing this be even slower than that?
snibgo
Posts: 12159
Joined: 2010-01-23T23:01:33-07:00
Authentication code: 1151
Location: England, UK

Re: Extremely weak captcha

Post by snibgo »

And when you crack it, the site will use a stronger captcha. You crack that one ... soon the captcha becomes impossible for even humans to read it.

Sorry, I won't help.
snibgo's IM pages: im.snibgo.com
Post Reply