We get about 100 enquiries a month through forms on our site. We completely rejected the option of CAPTCHA (although it had been requested by some colleagues) because of the accessibility issues; but also because it makes it harder for everyone to use, not just those with disabilities. I have 20/20 vision and I sometimes have difficulty deciphering CAPTCHAs.

Another possibility we considered was simply to classify any form submission with a URL in it as spam. Over 95% of the spam we used to receive contained a URL. So just add a note in the label of your form inputs to say ‘do not enter a URL’, and write a script so that any submission containing the string ‘http://’ is rejected.

Should the whole idea of CAPTCHAs as a concept be abandoned? It seems that few web designers know about alternatives, especially for blind and partially sighted people. But even if we attempt to educate more designers about alternative CAPTCHAs, is spam software not going to soon improve to the point that it is too smart for CAPTCHAs anyway?

My understanding has always been (correct me if I’m wrong) that the standard CAPTCHA – obscure letters on a busy background – was introduced to beat software that could read standard text and ‘know’ how to fill in a form based on replicating a piece of text. This is why web designers do not use alt text tags – the same software could read that alt text and fill in a form.

But I thought that artificial intelligence was moving forward quickly, including in the abilities of programs to understand images and audio. I have a friend who could probably use a PhD project to this end if he was so inclined. Stuart above seems to have found a good idea – but I wonder whether programs will soon be able to ‘think’ around this solution, or failing that, bombard developers like him with every potential solution to a question CAPTCHA.

Am I being crazily futuristic? Or should we look forward to a future in which we are all – regardless of ability to interact with CAPTCHAs – left waiting for hours or days for a human to authenticate online forms?

…I could ask if there will be programs in the future which forge online forms and then interact with authenticators, over the phone for example. But that’s crazy talk.

Rather than going down the route of a traditional CAPTCHA, I used PHP to generate two numbers – one between 1 and 50, and another between 1 and 5, the second number of the first number never goes beyond 5, so the sum’s answer never goes beyond the next 10 digit range (to make the sum easier). This is all wrapped in a label, so screenreader users can see the link between the question and the form and I’ve never had another bit of Spam since!

The only thing that worries me is that this might lock out users with poor numeracy – am I being too cautious? Here’s the form for reference:

http://www.lichfielddc.gov.uk/site/custom_scripts/feedback2.php

This isn’t really correct. The alternative description of an image should be the exact equivalent of its appearance. So if it’s a photo of Marilyn Monroe with no text in the image, it should just be ‘Marilyn Monroe’. However, if that image is also a hyperlink, the title attribute of the link itself can be used to describe where the link goes to.

http://webbytedd.com/aa/assorted-captcha/

I realize that the first demo is not acceptable, but do any other the other examples work for those with disabilities? Granted some won’t because they require sight, but blindness is only one of many different disabilities.

Could a combination of different CAPTCHA’s provide a solution or is CAPTCHA just one of the things that can not be resolved?

At this point, failure to provide at least an audio playback on any CAPTCHA represents nothing less than a “no blind people allowed” sign.