hello,
These are some approaches i can think of instead of a text based captcha.
The image idea where users are asked to spot the odd one out like
demonstrated or find all the similar images like mentioned in
here<https://www.mediawiki.org/wiki/CAPTCHA>
.
Also a picture with a part chipped in could be shown and chipped pictures
could be given as options
like find the missing part from a jigsaw puzzle.
The image which would be shown is
http://imgur.com/uefeb08
http://imgur.com/KEJqCg3 is the picture which would be the correct option.
The other options could be rotated versions of this , which would not be so
easy for the bot to match. (unless it somehow worked some digital
processing algorithm and matched the color gradients or something like
that).
This is a good option for people who do not know english or are illiterate
and maybe would not understand questions like : is this a bird , plane ,
superman? after being shown a picture.
Tell me what you think
(Sorry to upload those images on imgur. i dont know how to put them on the
wiki .Hope that is ok)
have posted this on the CAPTCHA
page<https://www.mediawiki.org/wiki/Talk:CAPTCHA>also