Ads Captcha

Audio captcha is supposed to be a solution for those who can’t see properly or have problems with figuring out the written texts on the captcha image, but it looks like the audio version is not better.
Is it really that bad?
The following captcha videos say it is…

As you may already know by now, Captcha is a common approach to prevent access of users that aren’t human to all kinds of websites. The captcha is a kind of test that requires verification of distorted image plus textual content which is deciphered easily by humans but not by computer bots. 
However, it appears that this simple system may also prevent access from a certain group of human being: disabled people such as blind, low-vision, or people who suffer from cognitive problems (dyslexia). Once a low vision user cannot decipher the image displayed on the Captcha, he cannot access the specific website that uses the captcha protection and thus can not open an account, comment on a forum or blog and so on.

To make a long story short - Captcha can tell human and bots apart but cannot recognize human with disabilities who are not bots and fail the test because of their disabilities…

Captcha Alternatives
But do not worry. There other alternatives for Captcha:

One of the alternative methods is a sound test also known as “audio captcha“. It requires the potential user to listen to some sounds which are played on a noisy background, filter the sounds and repeat them. It is a good solution for low vision or blind users, but not for deaf people or users who don’t have a good hearing.

 Other captcha alternatives are as follows:
Spam filtering – software for blogs contain spam filters targeted to delete spam messages. More advanced systems are able to control spam attacks and filter permanently or temporarily spam contents using the IP address of the user.

Heuristic checks – are based upon the user’s data such as requests, pages he has visited, IP address, data entry or signature data and assist in detecting robot users. 

Single sign-on – This system is similar to a passport. It utilizes visual verification. No doubt – it’s highly recommended for people with disabilities.  

Public key infrastructure solutions – This is another alternative solution not used yet but may help low vision users – to use certifications issued by government or other trusted authorities that verify their identities. The disabled user will have to telegraph the site, inform his or her disability and get access to the site’s service.

Biometrics – Another tool, to be used together with the single sign–on system (using D.N.A / fingerprints). Microsoft has already developed a new system of Biometric verification but it will take years until the biometric hardware will penetrate into the market.

 To sum up, Captcha is a good solution, but not for all. When it comes to disabled people with low vision or hearing and other disabilities, one must consider some other security tools and / or software, such as the captcha-alternatives mentioned on this post (spam filters, heuristic checks and so on).

Captcha is a test that comes to validate web users as humans (=rather than computer bots).
the captcha test can be used for site registration, for example – just before registration is completed the user is asked to copy an  image with distorted letters. Since those letters are captured in images and are displayed randomly, and bots can not “read” images, the CAPTCHA test suppose to “stop bots from passing the test and using the web for their inetrests”.

But what about people who suffer from some kind of sight impairment including blindness?
They can not solve the captcha test (they can not see the captcha image well and thus can not copy it) and thus, just like bots, can not register to sites and other online services that use captcha.
But do not worry, there’s a solution for this problem and it called: Audio Captcha.

People who suffer from sight impairment need to pass an audio captcha test in which they are asked to listen to a series of numbers or letters with a lot of background noise and then repeat them through typing the letters/numbers.
The idea is that humans can filter the background noise but a computer bot – can’t.

Unfortunately the audio captcha test is not perfect.
First, there are people who suffer from sight impairment / blindness that also have hearing problems.
Second, statistic shows that only 46% of audio captchas users are able to decipher the test and that the process takes 65 seconds at least , relatively much longer than a textual Captcha (about 12 seconds).
Third, most of the sites don’t use audio-captchas yet.

What other transformations will make the captcha test suitable for all?
Only time will tell…