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Re: Comment Spam: new trends, failing counter-measures and why it's a big deal
From: Valdis.Kletnieks () vt edu
Date: Mon, 13 Feb 2006 11:04:46 -0500
On Mon, 13 Feb 2006 07:09:48 +0100, php0t said:
the global solution against word recognition based challenges? If it was like that, it would mean that there is no way anybody could make an image generator that would change its success rate from 90% to 0%...
It's *really* *really* difficult to produce a graphic image of letters and numbers that is still recognizable to a human but can't be beaten by a good edge-detection algorithm. For instance, you can "bleed" the edges so that they're fuzzy - but then the human has a hard time telling if it's an 'i' or an 'l', or an 'h' or a 'b' (and so on). I suppose you *could* put up a picture of something, and ask "What is this a picture of" - but then you need a sufficiently large library of images that an attacker can't just download all of them and have a human name each one once. And of course, this has the danger that a user can be left saying: "WTF? Is that an antelope or a gazelle?"....
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Current thread:
- Comment Spam: new trends, failing counter-measures and why it's a big deal Gadi Evron (Feb 12)
- RE: Comment Spam: new trends, failing counter-measures and why it's a big deal php0t (Feb 12)
- RE: Comment Spam: new trends, failing counter-measures and why it's a big deal Nick FitzGerald (Feb 12)
- RE: Comment Spam: new trends, failing counter-measures and why it's a big deal php0t (Feb 12)
- Re: Comment Spam: new trends, failing counter-measures and why it's a big deal Gareth Davies (Feb 12)
- RE: Comment Spam: new trends, failing counter-measures and why it's a big deal php0t (Feb 12)
- Re: Comment Spam: new trends, failing counter-measures and why it's a big deal Valdis . Kletnieks (Feb 13)
- RE: Comment Spam: new trends, failing counter-measures and why it's a big deal php0t (Feb 13)
- RE: Comment Spam: new trends, failing counter-measures and why it's a big deal Nick FitzGerald (Feb 12)
- RE: Comment Spam: new trends, failing counter-measures and why it's a big deal php0t (Feb 12)
- Re: Comment Spam: new trends, failing counter-measures and why it's a big deal Andrew Haninger (Feb 12)