Need a random image warp to defeat web bots

[christopher]

Greetings!
I need a simple random image warp to defeat bots on a web email form
-- I am getting a hundred spams a day! I have looked at
http://www.jhlabs.com/ip/filters/ but there is no documentation and I
can't see how to use the classes, and java advanced imaging ( http://
java.sun.com/products/java-media/jai/forDevelopers/jai-apidocs/
index.html ) but I don't have a clue what lines like this mean:
"Computes the source subpixel positions for a given rectangular
destination region, subsampled with an integral period."
Sigh.

Surely someone has done the gunt work on this and is willing to share.

Thanx!
-- clh

 

[Chris Uppal]

I need a simple random image warp to defeat bots on a web email form
-- I am getting a hundred spams a day! I have looked at [...]

It might be worthwhile Googling for something like
java captcha generator
which seems to throw up some promising hits.

BTW, if your email address is indicative, it would be more appropriate to ask
each email submitter to solve a randomly choosen crossword clue ;-)

-- chris

 

[christopher]

thanx -- i did not know the term. the website is ancient, but so is
my google groups login hehe, and that is the *best* way to cut down
spam!

this looks promising:
http://simplecaptcha.sourceforge.net/

cheers!

I need a simple random image warp to defeat bots on a web email form
-- I am getting a hundred spams a day! I have looked at [...]

It might be worthwhile Googling for something like
java captcha generator
which seems to throw up some promising hits.

BTW, if your email address is indicative, it would be more appropriate to ask
each email submitter to solve a randomly choosen crossword clue ;-)

-- chris

 

[Richter~9.6]

I need a simple random image warp to defeat bots on a web email form
-- I am getting a hundred spams a day! I have looked at [...]

It might be worthwhile Googling for something like
java captcha generator
which seems to throw up some promising hits.

BTW, if your email address is indicative, it would be more appropriate to ask
each email submitter to solve a randomly choosen crossword clue ;-)

-- chris

The problem with captcha is that it shifts the burden of spam from the
webmaster onto the visitor. As a visitor it can be very annoying
trying to post a quick comment to a blog and having to do silly
puzzles or work out what warped obscure letters are...

A better solution would be to write your form into the page using
JavaScript (replacing the capture form possibly?) ... that way you
stop a large amount of spam because most harvesters just scan the html
for certain form tags - i.e. no parsing of JavaScript. If you really
wanted to keep out the spambots, add an onclick event to a 'button'
image to display the form instead. That way you also avoid spambots
that know how to parse JavaScript but might not know how to click an
image.

As a last resort, if the user has JavaScript turned off then the
captcha stuff is displayed (because the JavaScript would replace the
captcha form if it was enabled)...

Hope this helps.

Regards,
Richard

 

[christopher]

Richard -- fabulous input.
I was just going to post that the sourceforge captcha program requires
a GIU to be running (which of course on my server there is not),
because I guess somthing they were doing came from the AWT toolbox.
The dreaded "Can't connect to X11 window server using ':0.0' as the
value of the DISPLAY variable" after taking 1/2 hour to realize the
configuration info for the web.xml file was not suitable for my
setup. *sigh*

A better solution would be to write your form into the page using
JavaScript (replacing the capture form possibly?) ... that way you
stop a large amount of spam because most harvesters just scan the html
for certain form tags - i.e. no parsing of JavaScript. If you really
wanted to keep out the spambots, add an onclick event to a 'button'
image to display the form instead. That way you also avoid spambots
that know how to parse JavaScript but might not know how to click an
image.

I was just going to use the captcha for emails to the admin, but your
suggestion to bury the 'human confirmation' elsewhere on the page can
be used for any form / chat / forum entry. hehe how about an
onSubmit() popup that says 'click here is you are a human'. Can a bot
do that?

 

[Daniel Pitts]

Richard -- fabulous input.
I was just going to post that the sourceforge captcha program requires
a GIU to be running (which of course on my server there is not),
because I guess somthing they were doing came from the AWT toolbox.
The dreaded "Can't connect to X11 window server using ':0.0' as the
value of the DISPLAY variable" after taking 1/2 hour to realize the
configuration info for the web.xml file was not suitable for my
setup. *sigh*


I was just going to use the captcha for emails to the admin, but your
suggestion to bury the 'human confirmation' elsewhere on the page can
be used for any form / chat / forum entry. hehe how about an
onSubmit() popup that says 'click here is you are a human'. Can a bot
do that?

The answer is, "not yet".
The problem with all of this is that Spammers are getting smarter and
smarter. Some simple Capcha is thwarted by OCR technology. And some
Capcha is hard for me to read

 

[Lew]

The problem with all of this is that Spammers are getting smarter and
smarter. Some simple Capcha is thwarted by OCR technology. And some
Capcha is hard for me to read

And all this time I thought all these web sites were running color-blindness
tests.

- Lew