as thefool said: captcha is MADE to block machines, including OCR.
additionally, an everyday-login should NOT be limited by a captcha, just the registration should.
so there should be no NEED for you to crack captchas until you try to write spambots.
compare 2 bitmaps?
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Kaeru Gaman
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superadnim
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It's not like hes going to make millions with it if he accomplishes anything. Seriously, most captchas are not as good as you make them sound; that's the thing... talking crap makes some people run away, not me. (and by that I mean, make them seem better than they are).
First, you'll need a cool interface for bitmap manipulation - so you can forget about file formats and just deal with raw data.
Secondly, you'll need to clean your input data to a state where it becomes usable for you.
Most captchas, still, try to add noise and artifacts on lower gammas which means that you can effectively cut all that away and end up with a series of "binary images" (because we only have 2 colors now).
Either way, once you have cleaned the data, you'll need to separate it into glpyhs, once that's done, you'll need to register each glyph so it's rotation is nulled out. Once that's done, you can use your favorite method to identify each one of the glyphs, or a combination of them all.
The thing that makes good captchas good is the fact that they don't use public fonts, instead, private font sets. This means that in order to correctly train a neural net, you'll need to first get all the glyphs in the shape you'll be having them after the processing is done.
While some people avoid this step, it does bring their results down to 80% positives at most.
But you see, even if I talk about it without giving away the keywords the guy won't just do anything wrong... I think that no one should hide information from anyone at all.
There's also the common misconception that "neural nets are me god" and that's just bull, you don't need a neural net at all to identify a bunch of glyphs, specially when the captcha uses known fonts.
There are several distinct methods regarding captcha recognition, some companies actually sell their services! - But as mentioned captchas are there for a reason, however, with recaptchas... well, not so much. I don't agree on the creator's point of view regarding this subject. It's not as noble as he painted it to be.
Funny you should mention OCR... you know, recaptchas exist because current OCRs can't identify those sequences and thus, humans are required to identify them.
I am currently breaking a captcha from a NIC service where they use biased parameters to generate the final image. After analyzing over 5000 samples I concluded they only use 1 font and the rotation angles are 15° maximum, the noise is easily removed through equalization and as soon as I finish the segmentation code, I'll be able to identify those glyphs!
Lucky for me they don't distort the image, but if they did, I assume they would leave the grid visible... knowing how stupid they are
First, you'll need a cool interface for bitmap manipulation - so you can forget about file formats and just deal with raw data.
Secondly, you'll need to clean your input data to a state where it becomes usable for you.
Most captchas, still, try to add noise and artifacts on lower gammas which means that you can effectively cut all that away and end up with a series of "binary images" (because we only have 2 colors now).
Either way, once you have cleaned the data, you'll need to separate it into glpyhs, once that's done, you'll need to register each glyph so it's rotation is nulled out. Once that's done, you can use your favorite method to identify each one of the glyphs, or a combination of them all.
The thing that makes good captchas good is the fact that they don't use public fonts, instead, private font sets. This means that in order to correctly train a neural net, you'll need to first get all the glyphs in the shape you'll be having them after the processing is done.
While some people avoid this step, it does bring their results down to 80% positives at most.
But you see, even if I talk about it without giving away the keywords the guy won't just do anything wrong... I think that no one should hide information from anyone at all.
There's also the common misconception that "neural nets are me god" and that's just bull, you don't need a neural net at all to identify a bunch of glyphs, specially when the captcha uses known fonts.
There are several distinct methods regarding captcha recognition, some companies actually sell their services! - But as mentioned captchas are there for a reason, however, with recaptchas... well, not so much. I don't agree on the creator's point of view regarding this subject. It's not as noble as he painted it to be.
Funny you should mention OCR... you know, recaptchas exist because current OCRs can't identify those sequences and thus, humans are required to identify them.
I am currently breaking a captcha from a NIC service where they use biased parameters to generate the final image. After analyzing over 5000 samples I concluded they only use 1 font and the rotation angles are 15° maximum, the noise is easily removed through equalization and as soon as I finish the segmentation code, I'll be able to identify those glyphs!
Lucky for me they don't distort the image, but if they did, I assume they would leave the grid visible... knowing how stupid they are
should I bash the keyboard and give up? 
superadnim, i didn't point out captchas was impossible to break but MADE to be very hard to (if they aren't very hard, they don't archieve the goal). There is a reason they are here, and that is to protect against spammers and lowlife making good people spend their time on nothing but SHIT!
As said i do not believe there is a good reason to break captchas. That doesn't mean its not a fun thing to work with, but i doubt there is a reason (apart from having fun) that will benefit more than it hurts.
Wouldn't it be quite stupid to use known fonts? Well sure enough, people don't think all the time. But if we talk custom letters that gets angled, morphed, waved, disturbed, bended etc, you're not getting very far with traditional methods.There's also the common misconception that "neural nets are me god" and that's just bull, you don't need a neural net at all to identify a bunch of glyphs, specially when the captcha uses known fonts.
As said i do not believe there is a good reason to break captchas. That doesn't mean its not a fun thing to work with, but i doubt there is a reason (apart from having fun) that will benefit more than it hurts.
Re:
Hi, does anyone have time to code an example of the above DrawingBuffer() loop?AND51 wrote:Run through the two images, comparing pixel by pixel in a For-loop by reading the image buffer with DrawingBuffer().
Or a PureBasic version of AutoHotkey's "ImageSearch" function -> https://github.com/Lexikos/AutoHotkey_L ... .cpp#L4888