From: "ara.t.howard" Date: 2007-07-04T02:17:19+09:00 Subject: Re: [ANN] flatulent-0.0.1 ascii captcha for the masses On Jul 3, 2007, at 8:49 AM, SonOfLilit wrote: > With so little grid cells and so little possible transformations, > pattern matching is much much simpler. exactly which 'grid' are you referring to? there is no grid and there are no 'word' chars in the virutal grid. have you looked at the source? check out my response to brian. also, i'm not so sure that that it true: a modest sized ascii captcha has around 40960000 simple combinations. the current source uses an encoded timestamp which must be submitted with the captcha else it's invalid. that timestamp is only valid for a few minutes and that means a program would have to make around 20480000 posts (on average) to the same website within a few minutes to crack it using brute force. this seems highly unlikely to me. (ps. neither the timestamp not key are encode in the first release, but the repo one has this feature) the direction i'm heading is to have all virtual grid cells positioned via css. which means the only real way to construct a grid is to using a rendering engine first, and then to ocr the clipped image. i'm very confident that a) this can be done b) it's even more work than traditional captcha to decode c) it's 100 times less work for web developers i'm truly very interested in seeing if someone can actually crack this (i'm sure that they can) with a reasonable amount of effort. remembering that traditional captcha can be broken with a low-medium amount of effort yet reduces spam by around 98%. kind regards. -a -- we can deny everything, except that we have the possibility of being better. simply reflect on that. h.h. the 14th dalai lama