[thelist] CAPTCHA
Bob Meetin
bobm at dottedi.biz
Sat Aug 8 23:00:08 CDT 2009
Hassan Schroeder wrote:
> On Sat, Aug 8, 2009 at 6:38 PM, Jeremy Weiss<eccentric.one at gmail.com>
> wrote:
>
> I've seen CAPTCHAs that sucked, yes, but personally I'd be more
> inclined to just go with the "what's 2 + 2" question approach rather
> than stretch too far into interpretation based on what may not be a
> shared worldview.
>
> I know I shouldn't but can't resist. I regularly misread captcha -
> really detest them. However, simple math if fairly universally
> understood and works.
>
Side note - I'd swear that with Craigslist I've posted ads and if I get
80% of the characters right, they go through.
> If you want to take it to level 2, it'd be pretty easy to use
> imagemagick/convert to display two very readable (not pop art) images
> as numbers.
>
% convert -background white -fill black -border 5 -bordercolor white
-pointsize 30 label:'2 + 7 = ?' math.gif
Program in:
$result = $var1 + $var2
% convert -background white -fill black -border 5 -bordercolor white
-pointsize 30 label:'%var1 + $var2 = ?' math.gif
That being said in general I prefer if possible using techniques that
prevent spammers/spambots from filling in forms by addressing their
repetitive behavior patterns. Also someone (can't find the email) made a
super suggestion regarding placing a "administrator use only" field on
the form and if filled in, deny the submission.
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