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Re: Making A Better CAPTCHA For the Visually Impaired And Making Captions More Available To The Hearing Impaired

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From: Elle
Date: Apr 18, 2013 6:30AM

Samir:

Regarding support for deaf-blind users, you may find help in using the CSS
media type <style type="text/css" *media*="braille, embossed">. I'm still
considering how it could be used effectively and still meet the goals for
security. Perhaps you could find a way to utilize the tactile nature of a
braille display, maybe that could be leveraged to send a haptic prompt that
only that form of assistive technology could comprehend - not sure, though.
It seems a bit convoluted. Comprehension tests are difficult and usually
inaccessible to some users with cognitive impairments, so I would caution
against that solution.

One of the overarching challenges that you will face, even after you solve
for every scenario, is one of time and discomfort. When you increase the
possible methods for solving the puzzle, you increase the time it takes to
solve the CAPTCHA. Users will likely abandon the experience before
completing the task. When you make it faster, it's probably going to leave
some user group locked out. Abandonment rate is already an issue with
CAPTCHA, and there's reasons why. CAPTCHA is hard for everyone, and CAPTCHA
really isn't fair to the user. A security check puts a technical problem
squarely onto the shoulders of the end-user to solve. As a user, I often
think, "Why is your security issue my problem now?" Generally speaking,
usability best practices would recommend that a web page is designed to
make an experience easier for a user, not harder. CAPTCHA tends to conflict
with this concept. When we encounter CAPTCHA on our clients' web pages, we
typically recommend a layered alternative solution that works better all
around: more secure and more accessible. I'm not saying you can't solve
this puzzle (irony!), but I do think there are quite a few challenges ahead
to get there.

All the best,
Elle